diff options
Diffstat (limited to 'gcc-4.8.1/gcc/cp/typeck.c')
| -rw-r--r-- | gcc-4.8.1/gcc/cp/typeck.c | 8964 |
1 files changed, 0 insertions, 8964 deletions
diff --git a/gcc-4.8.1/gcc/cp/typeck.c b/gcc-4.8.1/gcc/cp/typeck.c deleted file mode 100644 index 21b5d414b..000000000 --- a/gcc-4.8.1/gcc/cp/typeck.c +++ /dev/null @@ -1,8964 +0,0 @@ -/* Build expressions with type checking for C++ compiler. - Copyright (C) 1987-2013 Free Software Foundation, Inc. - Hacked by Michael Tiemann (tiemann@cygnus.com) - -This file is part of GCC. - -GCC is free software; you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation; either version 3, or (at your option) -any later version. - -GCC is distributed in the hope that it will be useful, -but WITHOUT ANY WARRANTY; without even the implied warranty of -MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -GNU General Public License for more details. - -You should have received a copy of the GNU General Public License -along with GCC; see the file COPYING3. If not see -<http://www.gnu.org/licenses/>. */ - - -/* This file is part of the C++ front end. - It contains routines to build C++ expressions given their operands, - including computing the types of the result, C and C++ specific error - checks, and some optimization. */ - -#include "config.h" -#include "system.h" -#include "coretypes.h" -#include "tm.h" -#include "tree.h" -#include "cp-tree.h" -#include "flags.h" -#include "diagnostic.h" -#include "intl.h" -#include "target.h" -#include "convert.h" -#include "c-family/c-common.h" -#include "c-family/c-objc.h" -#include "params.h" - -static tree pfn_from_ptrmemfunc (tree); -static tree delta_from_ptrmemfunc (tree); -static tree convert_for_assignment (tree, tree, impl_conv_rhs, tree, int, - tsubst_flags_t, int); -static tree cp_pointer_int_sum (enum tree_code, tree, tree); -static tree rationalize_conditional_expr (enum tree_code, tree, - tsubst_flags_t); -static int comp_ptr_ttypes_real (tree, tree, int); -static bool comp_except_types (tree, tree, bool); -static bool comp_array_types (const_tree, const_tree, bool); -static tree pointer_diff (tree, tree, tree, tsubst_flags_t); -static tree get_delta_difference (tree, tree, bool, bool, tsubst_flags_t); -static void casts_away_constness_r (tree *, tree *, tsubst_flags_t); -static bool casts_away_constness (tree, tree, tsubst_flags_t); -static void maybe_warn_about_returning_address_of_local (tree); -static tree lookup_destructor (tree, tree, tree); -static void warn_args_num (location_t, tree, bool); -static int convert_arguments (tree, vec<tree, va_gc> **, tree, int, - tsubst_flags_t); - -/* Do `exp = require_complete_type (exp);' to make sure exp - does not have an incomplete type. (That includes void types.) - Returns error_mark_node if the VALUE does not have - complete type when this function returns. */ - -tree -require_complete_type_sfinae (tree value, tsubst_flags_t complain) -{ - tree type; - - if (processing_template_decl || value == error_mark_node) - return value; - - if (TREE_CODE (value) == OVERLOAD) - type = unknown_type_node; - else - type = TREE_TYPE (value); - - if (type == error_mark_node) - return error_mark_node; - - /* First, detect a valid value with a complete type. */ - if (COMPLETE_TYPE_P (type)) - return value; - - if (complete_type_or_maybe_complain (type, value, complain)) - return value; - else - return error_mark_node; -} - -tree -require_complete_type (tree value) -{ - return require_complete_type_sfinae (value, tf_warning_or_error); -} - -/* Try to complete TYPE, if it is incomplete. For example, if TYPE is - a template instantiation, do the instantiation. Returns TYPE, - whether or not it could be completed, unless something goes - horribly wrong, in which case the error_mark_node is returned. */ - -tree -complete_type (tree type) -{ - if (type == NULL_TREE) - /* Rather than crash, we return something sure to cause an error - at some point. */ - return error_mark_node; - - if (type == error_mark_node || COMPLETE_TYPE_P (type)) - ; - else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type)) - { - tree t = complete_type (TREE_TYPE (type)); - unsigned int needs_constructing, has_nontrivial_dtor; - if (COMPLETE_TYPE_P (t) && !dependent_type_p (type)) - layout_type (type); - needs_constructing - = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t)); - has_nontrivial_dtor - = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t)); - for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t)) - { - TYPE_NEEDS_CONSTRUCTING (t) = needs_constructing; - TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = has_nontrivial_dtor; - } - } - else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INSTANTIATION (type)) - instantiate_class_template (TYPE_MAIN_VARIANT (type)); - - return type; -} - -/* Like complete_type, but issue an error if the TYPE cannot be completed. - VALUE is used for informative diagnostics. - Returns NULL_TREE if the type cannot be made complete. */ - -tree -complete_type_or_maybe_complain (tree type, tree value, tsubst_flags_t complain) -{ - type = complete_type (type); - if (type == error_mark_node) - /* We already issued an error. */ - return NULL_TREE; - else if (!COMPLETE_TYPE_P (type)) - { - if (complain & tf_error) - cxx_incomplete_type_diagnostic (value, type, DK_ERROR); - return NULL_TREE; - } - else - return type; -} - -tree -complete_type_or_else (tree type, tree value) -{ - return complete_type_or_maybe_complain (type, value, tf_warning_or_error); -} - -/* Return truthvalue of whether type of EXP is instantiated. */ - -int -type_unknown_p (const_tree exp) -{ - return (TREE_CODE (exp) == TREE_LIST - || TREE_TYPE (exp) == unknown_type_node); -} - - -/* Return the common type of two parameter lists. - We assume that comptypes has already been done and returned 1; - if that isn't so, this may crash. - - As an optimization, free the space we allocate if the parameter - lists are already common. */ - -static tree -commonparms (tree p1, tree p2) -{ - tree oldargs = p1, newargs, n; - int i, len; - int any_change = 0; - - len = list_length (p1); - newargs = tree_last (p1); - - if (newargs == void_list_node) - i = 1; - else - { - i = 0; - newargs = 0; - } - - for (; i < len; i++) - newargs = tree_cons (NULL_TREE, NULL_TREE, newargs); - - n = newargs; - - for (i = 0; p1; - p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n), i++) - { - if (TREE_PURPOSE (p1) && !TREE_PURPOSE (p2)) - { - TREE_PURPOSE (n) = TREE_PURPOSE (p1); - any_change = 1; - } - else if (! TREE_PURPOSE (p1)) - { - if (TREE_PURPOSE (p2)) - { - TREE_PURPOSE (n) = TREE_PURPOSE (p2); - any_change = 1; - } - } - else - { - if (1 != simple_cst_equal (TREE_PURPOSE (p1), TREE_PURPOSE (p2))) - any_change = 1; - TREE_PURPOSE (n) = TREE_PURPOSE (p2); - } - if (TREE_VALUE (p1) != TREE_VALUE (p2)) - { - any_change = 1; - TREE_VALUE (n) = merge_types (TREE_VALUE (p1), TREE_VALUE (p2)); - } - else - TREE_VALUE (n) = TREE_VALUE (p1); - } - if (! any_change) - return oldargs; - - return newargs; -} - -/* Given a type, perhaps copied for a typedef, - find the "original" version of it. */ -static tree -original_type (tree t) -{ - int quals = cp_type_quals (t); - while (t != error_mark_node - && TYPE_NAME (t) != NULL_TREE) - { - tree x = TYPE_NAME (t); - if (TREE_CODE (x) != TYPE_DECL) - break; - x = DECL_ORIGINAL_TYPE (x); - if (x == NULL_TREE) - break; - t = x; - } - return cp_build_qualified_type (t, quals); -} - -/* Return the common type for two arithmetic types T1 and T2 under the - usual arithmetic conversions. The default conversions have already - been applied, and enumerated types converted to their compatible - integer types. */ - -static tree -cp_common_type (tree t1, tree t2) -{ - enum tree_code code1 = TREE_CODE (t1); - enum tree_code code2 = TREE_CODE (t2); - tree attributes; - - - /* In what follows, we slightly generalize the rules given in [expr] so - as to deal with `long long' and `complex'. First, merge the - attributes. */ - attributes = (*targetm.merge_type_attributes) (t1, t2); - - if (SCOPED_ENUM_P (t1) || SCOPED_ENUM_P (t2)) - { - if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2)) - return build_type_attribute_variant (t1, attributes); - else - return NULL_TREE; - } - - /* FIXME: Attributes. */ - gcc_assert (ARITHMETIC_TYPE_P (t1) - || TREE_CODE (t1) == VECTOR_TYPE - || UNSCOPED_ENUM_P (t1)); - gcc_assert (ARITHMETIC_TYPE_P (t2) - || TREE_CODE (t2) == VECTOR_TYPE - || UNSCOPED_ENUM_P (t2)); - - /* If one type is complex, form the common type of the non-complex - components, then make that complex. Use T1 or T2 if it is the - required type. */ - if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE) - { - tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1; - tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2; - tree subtype - = type_after_usual_arithmetic_conversions (subtype1, subtype2); - - if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype) - return build_type_attribute_variant (t1, attributes); - else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype) - return build_type_attribute_variant (t2, attributes); - else - return build_type_attribute_variant (build_complex_type (subtype), - attributes); - } - - if (code1 == VECTOR_TYPE) - { - /* When we get here we should have two vectors of the same size. - Just prefer the unsigned one if present. */ - if (TYPE_UNSIGNED (t1)) - return build_type_attribute_variant (t1, attributes); - else - return build_type_attribute_variant (t2, attributes); - } - - /* If only one is real, use it as the result. */ - if (code1 == REAL_TYPE && code2 != REAL_TYPE) - return build_type_attribute_variant (t1, attributes); - if (code2 == REAL_TYPE && code1 != REAL_TYPE) - return build_type_attribute_variant (t2, attributes); - - /* Both real or both integers; use the one with greater precision. */ - if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2)) - return build_type_attribute_variant (t1, attributes); - else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1)) - return build_type_attribute_variant (t2, attributes); - - /* The types are the same; no need to do anything fancy. */ - if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2)) - return build_type_attribute_variant (t1, attributes); - - if (code1 != REAL_TYPE) - { - /* If one is unsigned long long, then convert the other to unsigned - long long. */ - if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node) - || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node)) - return build_type_attribute_variant (long_long_unsigned_type_node, - attributes); - /* If one is a long long, and the other is an unsigned long, and - long long can represent all the values of an unsigned long, then - convert to a long long. Otherwise, convert to an unsigned long - long. Otherwise, if either operand is long long, convert the - other to long long. - - Since we're here, we know the TYPE_PRECISION is the same; - therefore converting to long long cannot represent all the values - of an unsigned long, so we choose unsigned long long in that - case. */ - if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node) - || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node)) - { - tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2)) - ? long_long_unsigned_type_node - : long_long_integer_type_node); - return build_type_attribute_variant (t, attributes); - } - if (int128_integer_type_node != NULL_TREE - && (same_type_p (TYPE_MAIN_VARIANT (t1), - int128_integer_type_node) - || same_type_p (TYPE_MAIN_VARIANT (t2), - int128_integer_type_node))) - { - tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2)) - ? int128_unsigned_type_node - : int128_integer_type_node); - return build_type_attribute_variant (t, attributes); - } - - /* Go through the same procedure, but for longs. */ - if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node) - || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node)) - return build_type_attribute_variant (long_unsigned_type_node, - attributes); - if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node) - || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node)) - { - tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2)) - ? long_unsigned_type_node : long_integer_type_node); - return build_type_attribute_variant (t, attributes); - } - /* Otherwise prefer the unsigned one. */ - if (TYPE_UNSIGNED (t1)) - return build_type_attribute_variant (t1, attributes); - else - return build_type_attribute_variant (t2, attributes); - } - else - { - if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node) - || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node)) - return build_type_attribute_variant (long_double_type_node, - attributes); - if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node) - || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node)) - return build_type_attribute_variant (double_type_node, - attributes); - if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node) - || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node)) - return build_type_attribute_variant (float_type_node, - attributes); - - /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of - the standard C++ floating-point types. Logic earlier in this - function has already eliminated the possibility that - TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no - compelling reason to choose one or the other. */ - return build_type_attribute_variant (t1, attributes); - } -} - -/* T1 and T2 are arithmetic or enumeration types. Return the type - that will result from the "usual arithmetic conversions" on T1 and - T2 as described in [expr]. */ - -tree -type_after_usual_arithmetic_conversions (tree t1, tree t2) -{ - gcc_assert (ARITHMETIC_TYPE_P (t1) - || TREE_CODE (t1) == VECTOR_TYPE - || UNSCOPED_ENUM_P (t1)); - gcc_assert (ARITHMETIC_TYPE_P (t2) - || TREE_CODE (t2) == VECTOR_TYPE - || UNSCOPED_ENUM_P (t2)); - - /* Perform the integral promotions. We do not promote real types here. */ - if (INTEGRAL_OR_ENUMERATION_TYPE_P (t1) - && INTEGRAL_OR_ENUMERATION_TYPE_P (t2)) - { - t1 = type_promotes_to (t1); - t2 = type_promotes_to (t2); - } - - return cp_common_type (t1, t2); -} - -static void -composite_pointer_error (diagnostic_t kind, tree t1, tree t2, - composite_pointer_operation operation) -{ - switch (operation) - { - case CPO_COMPARISON: - emit_diagnostic (kind, input_location, 0, - "comparison between " - "distinct pointer types %qT and %qT lacks a cast", - t1, t2); - break; - case CPO_CONVERSION: - emit_diagnostic (kind, input_location, 0, - "conversion between " - "distinct pointer types %qT and %qT lacks a cast", - t1, t2); - break; - case CPO_CONDITIONAL_EXPR: - emit_diagnostic (kind, input_location, 0, - "conditional expression between " - "distinct pointer types %qT and %qT lacks a cast", - t1, t2); - break; - default: - gcc_unreachable (); - } -} - -/* Subroutine of composite_pointer_type to implement the recursive - case. See that function for documentation of the parameters. */ - -static tree -composite_pointer_type_r (tree t1, tree t2, - composite_pointer_operation operation, - tsubst_flags_t complain) -{ - tree pointee1; - tree pointee2; - tree result_type; - tree attributes; - - /* Determine the types pointed to by T1 and T2. */ - if (TREE_CODE (t1) == POINTER_TYPE) - { - pointee1 = TREE_TYPE (t1); - pointee2 = TREE_TYPE (t2); - } - else - { - pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1); - pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2); - } - - /* [expr.rel] - - Otherwise, the composite pointer type is a pointer type - similar (_conv.qual_) to the type of one of the operands, - with a cv-qualification signature (_conv.qual_) that is the - union of the cv-qualification signatures of the operand - types. */ - if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2)) - result_type = pointee1; - else if ((TREE_CODE (pointee1) == POINTER_TYPE - && TREE_CODE (pointee2) == POINTER_TYPE) - || (TYPE_PTRMEM_P (pointee1) && TYPE_PTRMEM_P (pointee2))) - { - result_type = composite_pointer_type_r (pointee1, pointee2, operation, - complain); - if (result_type == error_mark_node) - return error_mark_node; - } - else - { - if (complain & tf_error) - composite_pointer_error (DK_PERMERROR, t1, t2, operation); - else - return error_mark_node; - result_type = void_type_node; - } - result_type = cp_build_qualified_type (result_type, - (cp_type_quals (pointee1) - | cp_type_quals (pointee2))); - /* If the original types were pointers to members, so is the - result. */ - if (TYPE_PTRMEM_P (t1)) - { - if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1), - TYPE_PTRMEM_CLASS_TYPE (t2))) - { - if (complain & tf_error) - composite_pointer_error (DK_PERMERROR, t1, t2, operation); - else - return error_mark_node; - } - result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1), - result_type); - } - else - result_type = build_pointer_type (result_type); - - /* Merge the attributes. */ - attributes = (*targetm.merge_type_attributes) (t1, t2); - return build_type_attribute_variant (result_type, attributes); -} - -/* Return the composite pointer type (see [expr.rel]) for T1 and T2. - ARG1 and ARG2 are the values with those types. The OPERATION is to - describe the operation between the pointer types, - in case an error occurs. - - This routine also implements the computation of a common type for - pointers-to-members as per [expr.eq]. */ - -tree -composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2, - composite_pointer_operation operation, - tsubst_flags_t complain) -{ - tree class1; - tree class2; - - /* [expr.rel] - - If one operand is a null pointer constant, the composite pointer - type is the type of the other operand. */ - if (null_ptr_cst_p (arg1)) - return t2; - if (null_ptr_cst_p (arg2)) - return t1; - - /* We have: - - [expr.rel] - - If one of the operands has type "pointer to cv1 void*", then - the other has type "pointer to cv2T", and the composite pointer - type is "pointer to cv12 void", where cv12 is the union of cv1 - and cv2. - - If either type is a pointer to void, make sure it is T1. */ - if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2))) - { - tree t; - t = t1; - t1 = t2; - t2 = t; - } - - /* Now, if T1 is a pointer to void, merge the qualifiers. */ - if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1))) - { - tree attributes; - tree result_type; - - if (TYPE_PTRFN_P (t2) && (complain & tf_error)) - { - switch (operation) - { - case CPO_COMPARISON: - pedwarn (input_location, OPT_Wpedantic, - "ISO C++ forbids comparison between " - "pointer of type %<void *%> and pointer-to-function"); - break; - case CPO_CONVERSION: - pedwarn (input_location, OPT_Wpedantic, - "ISO C++ forbids conversion between " - "pointer of type %<void *%> and pointer-to-function"); - break; - case CPO_CONDITIONAL_EXPR: - pedwarn (input_location, OPT_Wpedantic, - "ISO C++ forbids conditional expression between " - "pointer of type %<void *%> and pointer-to-function"); - break; - default: - gcc_unreachable (); - } - } - result_type - = cp_build_qualified_type (void_type_node, - (cp_type_quals (TREE_TYPE (t1)) - | cp_type_quals (TREE_TYPE (t2)))); - result_type = build_pointer_type (result_type); - /* Merge the attributes. */ - attributes = (*targetm.merge_type_attributes) (t1, t2); - return build_type_attribute_variant (result_type, attributes); - } - - if (c_dialect_objc () && TREE_CODE (t1) == POINTER_TYPE - && TREE_CODE (t2) == POINTER_TYPE) - { - if (objc_have_common_type (t1, t2, -3, NULL_TREE)) - return objc_common_type (t1, t2); - } - - /* [expr.eq] permits the application of a pointer conversion to - bring the pointers to a common type. */ - if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE - && CLASS_TYPE_P (TREE_TYPE (t1)) - && CLASS_TYPE_P (TREE_TYPE (t2)) - && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1), - TREE_TYPE (t2))) - { - class1 = TREE_TYPE (t1); - class2 = TREE_TYPE (t2); - - if (DERIVED_FROM_P (class1, class2)) - t2 = (build_pointer_type - (cp_build_qualified_type (class1, cp_type_quals (class2)))); - else if (DERIVED_FROM_P (class2, class1)) - t1 = (build_pointer_type - (cp_build_qualified_type (class2, cp_type_quals (class1)))); - else - { - if (complain & tf_error) - composite_pointer_error (DK_ERROR, t1, t2, operation); - return error_mark_node; - } - } - /* [expr.eq] permits the application of a pointer-to-member - conversion to change the class type of one of the types. */ - else if (TYPE_PTRMEM_P (t1) - && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1), - TYPE_PTRMEM_CLASS_TYPE (t2))) - { - class1 = TYPE_PTRMEM_CLASS_TYPE (t1); - class2 = TYPE_PTRMEM_CLASS_TYPE (t2); - - if (DERIVED_FROM_P (class1, class2)) - t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1)); - else if (DERIVED_FROM_P (class2, class1)) - t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2)); - else - { - if (complain & tf_error) - switch (operation) - { - case CPO_COMPARISON: - error ("comparison between distinct " - "pointer-to-member types %qT and %qT lacks a cast", - t1, t2); - break; - case CPO_CONVERSION: - error ("conversion between distinct " - "pointer-to-member types %qT and %qT lacks a cast", - t1, t2); - break; - case CPO_CONDITIONAL_EXPR: - error ("conditional expression between distinct " - "pointer-to-member types %qT and %qT lacks a cast", - t1, t2); - break; - default: - gcc_unreachable (); - } - return error_mark_node; - } - } - - return composite_pointer_type_r (t1, t2, operation, complain); -} - -/* Return the merged type of two types. - We assume that comptypes has already been done and returned 1; - if that isn't so, this may crash. - - This just combines attributes and default arguments; any other - differences would cause the two types to compare unalike. */ - -tree -merge_types (tree t1, tree t2) -{ - enum tree_code code1; - enum tree_code code2; - tree attributes; - - /* Save time if the two types are the same. */ - if (t1 == t2) - return t1; - if (original_type (t1) == original_type (t2)) - return t1; - - /* If one type is nonsense, use the other. */ - if (t1 == error_mark_node) - return t2; - if (t2 == error_mark_node) - return t1; - - /* Handle merging an auto redeclaration with a previous deduced - return type. */ - if (is_auto (t1)) - return t2; - - /* Merge the attributes. */ - attributes = (*targetm.merge_type_attributes) (t1, t2); - - if (TYPE_PTRMEMFUNC_P (t1)) - t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1); - if (TYPE_PTRMEMFUNC_P (t2)) - t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2); - - code1 = TREE_CODE (t1); - code2 = TREE_CODE (t2); - if (code1 != code2) - { - gcc_assert (code1 == TYPENAME_TYPE || code2 == TYPENAME_TYPE); - if (code1 == TYPENAME_TYPE) - { - t1 = resolve_typename_type (t1, /*only_current_p=*/true); - code1 = TREE_CODE (t1); - } - else - { - t2 = resolve_typename_type (t2, /*only_current_p=*/true); - code2 = TREE_CODE (t2); - } - } - - switch (code1) - { - case POINTER_TYPE: - case REFERENCE_TYPE: - /* For two pointers, do this recursively on the target type. */ - { - tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2)); - int quals = cp_type_quals (t1); - - if (code1 == POINTER_TYPE) - t1 = build_pointer_type (target); - else - t1 = cp_build_reference_type (target, TYPE_REF_IS_RVALUE (t1)); - t1 = build_type_attribute_variant (t1, attributes); - t1 = cp_build_qualified_type (t1, quals); - - if (TREE_CODE (target) == METHOD_TYPE) - t1 = build_ptrmemfunc_type (t1); - - return t1; - } - - case OFFSET_TYPE: - { - int quals; - tree pointee; - quals = cp_type_quals (t1); - pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1), - TYPE_PTRMEM_POINTED_TO_TYPE (t2)); - t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1), - pointee); - t1 = cp_build_qualified_type (t1, quals); - break; - } - - case ARRAY_TYPE: - { - tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2)); - /* Save space: see if the result is identical to one of the args. */ - if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1)) - return build_type_attribute_variant (t1, attributes); - if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2)) - return build_type_attribute_variant (t2, attributes); - /* Merge the element types, and have a size if either arg has one. */ - t1 = build_cplus_array_type - (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2)); - break; - } - - case FUNCTION_TYPE: - /* Function types: prefer the one that specified arg types. - If both do, merge the arg types. Also merge the return types. */ - { - tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2)); - tree p1 = TYPE_ARG_TYPES (t1); - tree p2 = TYPE_ARG_TYPES (t2); - tree parms; - tree rval, raises; - - /* Save space: see if the result is identical to one of the args. */ - if (valtype == TREE_TYPE (t1) && ! p2) - return cp_build_type_attribute_variant (t1, attributes); - if (valtype == TREE_TYPE (t2) && ! p1) - return cp_build_type_attribute_variant (t2, attributes); - - /* Simple way if one arg fails to specify argument types. */ - if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node) - parms = p2; - else if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node) - parms = p1; - else - parms = commonparms (p1, p2); - - rval = build_function_type (valtype, parms); - gcc_assert (type_memfn_quals (t1) == type_memfn_quals (t2)); - gcc_assert (type_memfn_rqual (t1) == type_memfn_rqual (t2)); - rval = apply_memfn_quals (rval, - type_memfn_quals (t1), - type_memfn_rqual (t1)); - raises = merge_exception_specifiers (TYPE_RAISES_EXCEPTIONS (t1), - TYPE_RAISES_EXCEPTIONS (t2), - NULL_TREE); - t1 = build_exception_variant (rval, raises); - break; - } - - case METHOD_TYPE: - { - /* Get this value the long way, since TYPE_METHOD_BASETYPE - is just the main variant of this. */ - tree basetype = class_of_this_parm (t2); - tree raises = merge_exception_specifiers (TYPE_RAISES_EXCEPTIONS (t1), - TYPE_RAISES_EXCEPTIONS (t2), - NULL_TREE); - cp_ref_qualifier rqual = type_memfn_rqual (t1); - tree t3; - - /* If this was a member function type, get back to the - original type of type member function (i.e., without - the class instance variable up front. */ - t1 = build_function_type (TREE_TYPE (t1), - TREE_CHAIN (TYPE_ARG_TYPES (t1))); - t2 = build_function_type (TREE_TYPE (t2), - TREE_CHAIN (TYPE_ARG_TYPES (t2))); - t3 = merge_types (t1, t2); - t3 = build_method_type_directly (basetype, TREE_TYPE (t3), - TYPE_ARG_TYPES (t3)); - t1 = build_exception_variant (t3, raises); - t1 = build_ref_qualified_type (t1, rqual); - break; - } - - case TYPENAME_TYPE: - /* There is no need to merge attributes into a TYPENAME_TYPE. - When the type is instantiated it will have whatever - attributes result from the instantiation. */ - return t1; - - default:; - } - - if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes)) - return t1; - else if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes)) - return t2; - else - return cp_build_type_attribute_variant (t1, attributes); -} - -/* Return the ARRAY_TYPE type without its domain. */ - -tree -strip_array_domain (tree type) -{ - tree t2; - gcc_assert (TREE_CODE (type) == ARRAY_TYPE); - if (TYPE_DOMAIN (type) == NULL_TREE) - return type; - t2 = build_cplus_array_type (TREE_TYPE (type), NULL_TREE); - return cp_build_type_attribute_variant (t2, TYPE_ATTRIBUTES (type)); -} - -/* Wrapper around cp_common_type that is used by c-common.c and other - front end optimizations that remove promotions. - - Return the common type for two arithmetic types T1 and T2 under the - usual arithmetic conversions. The default conversions have already - been applied, and enumerated types converted to their compatible - integer types. */ - -tree -common_type (tree t1, tree t2) -{ - /* If one type is nonsense, use the other */ - if (t1 == error_mark_node) - return t2; - if (t2 == error_mark_node) - return t1; - - return cp_common_type (t1, t2); -} - -/* Return the common type of two pointer types T1 and T2. This is the - type for the result of most arithmetic operations if the operands - have the given two types. - - We assume that comp_target_types has already been done and returned - nonzero; if that isn't so, this may crash. */ - -tree -common_pointer_type (tree t1, tree t2) -{ - gcc_assert ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2)) - || (TYPE_PTRDATAMEM_P (t1) && TYPE_PTRDATAMEM_P (t2)) - || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2))); - - return composite_pointer_type (t1, t2, error_mark_node, error_mark_node, - CPO_CONVERSION, tf_warning_or_error); -} - -/* Compare two exception specifier types for exactness or subsetness, if - allowed. Returns false for mismatch, true for match (same, or - derived and !exact). - - [except.spec] "If a class X ... objects of class X or any class publicly - and unambiguously derived from X. Similarly, if a pointer type Y * ... - exceptions of type Y * or that are pointers to any type publicly and - unambiguously derived from Y. Otherwise a function only allows exceptions - that have the same type ..." - This does not mention cv qualifiers and is different to what throw - [except.throw] and catch [except.catch] will do. They will ignore the - top level cv qualifiers, and allow qualifiers in the pointer to class - example. - - We implement the letter of the standard. */ - -static bool -comp_except_types (tree a, tree b, bool exact) -{ - if (same_type_p (a, b)) - return true; - else if (!exact) - { - if (cp_type_quals (a) || cp_type_quals (b)) - return false; - - if (TREE_CODE (a) == POINTER_TYPE - && TREE_CODE (b) == POINTER_TYPE) - { - a = TREE_TYPE (a); - b = TREE_TYPE (b); - if (cp_type_quals (a) || cp_type_quals (b)) - return false; - } - - if (TREE_CODE (a) != RECORD_TYPE - || TREE_CODE (b) != RECORD_TYPE) - return false; - - if (publicly_uniquely_derived_p (a, b)) - return true; - } - return false; -} - -/* Return true if TYPE1 and TYPE2 are equivalent exception specifiers. - If EXACT is ce_derived, T2 can be stricter than T1 (according to 15.4/5). - If EXACT is ce_normal, the compatibility rules in 15.4/3 apply. - If EXACT is ce_exact, the specs must be exactly the same. Exception lists - are unordered, but we've already filtered out duplicates. Most lists will - be in order, we should try to make use of that. */ - -bool -comp_except_specs (const_tree t1, const_tree t2, int exact) -{ - const_tree probe; - const_tree base; - int length = 0; - - if (t1 == t2) - return true; - - /* First handle noexcept. */ - if (exact < ce_exact) - { - /* noexcept(false) is compatible with no exception-specification, - and stricter than any spec. */ - if (t1 == noexcept_false_spec) - return t2 == NULL_TREE || exact == ce_derived; - /* Even a derived noexcept(false) is compatible with no - exception-specification. */ - if (t2 == noexcept_false_spec) - return t1 == NULL_TREE; - - /* Otherwise, if we aren't looking for an exact match, noexcept is - equivalent to throw(). */ - if (t1 == noexcept_true_spec) - t1 = empty_except_spec; - if (t2 == noexcept_true_spec) - t2 = empty_except_spec; - } - - /* If any noexcept is left, it is only comparable to itself; - either we're looking for an exact match or we're redeclaring a - template with dependent noexcept. */ - if ((t1 && TREE_PURPOSE (t1)) - || (t2 && TREE_PURPOSE (t2))) - return (t1 && t2 - && cp_tree_equal (TREE_PURPOSE (t1), TREE_PURPOSE (t2))); - - if (t1 == NULL_TREE) /* T1 is ... */ - return t2 == NULL_TREE || exact == ce_derived; - if (!TREE_VALUE (t1)) /* t1 is EMPTY */ - return t2 != NULL_TREE && !TREE_VALUE (t2); - if (t2 == NULL_TREE) /* T2 is ... */ - return false; - if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */ - return exact == ce_derived; - - /* Neither set is ... or EMPTY, make sure each part of T2 is in T1. - Count how many we find, to determine exactness. For exact matching and - ordered T1, T2, this is an O(n) operation, otherwise its worst case is - O(nm). */ - for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2)) - { - for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe)) - { - tree a = TREE_VALUE (probe); - tree b = TREE_VALUE (t2); - - if (comp_except_types (a, b, exact)) - { - if (probe == base && exact > ce_derived) - base = TREE_CHAIN (probe); - length++; - break; - } - } - if (probe == NULL_TREE) - return false; - } - return exact == ce_derived || base == NULL_TREE || length == list_length (t1); -} - -/* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if - [] can match [size]. */ - -static bool -comp_array_types (const_tree t1, const_tree t2, bool allow_redeclaration) -{ - tree d1; - tree d2; - tree max1, max2; - - if (t1 == t2) - return true; - - /* The type of the array elements must be the same. */ - if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2))) - return false; - - d1 = TYPE_DOMAIN (t1); - d2 = TYPE_DOMAIN (t2); - - if (d1 == d2) - return true; - - /* If one of the arrays is dimensionless, and the other has a - dimension, they are of different types. However, it is valid to - write: - - extern int a[]; - int a[3]; - - by [basic.link]: - - declarations for an array object can specify - array types that differ by the presence or absence of a major - array bound (_dcl.array_). */ - if (!d1 || !d2) - return allow_redeclaration; - - /* Check that the dimensions are the same. */ - - if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))) - return false; - max1 = TYPE_MAX_VALUE (d1); - max2 = TYPE_MAX_VALUE (d2); - if (processing_template_decl && !abi_version_at_least (2) - && !value_dependent_expression_p (max1) - && !value_dependent_expression_p (max2)) - { - /* With abi-1 we do not fold non-dependent array bounds, (and - consequently mangle them incorrectly). We must therefore - fold them here, to verify the domains have the same - value. */ - max1 = fold (max1); - max2 = fold (max2); - } - - if (!cp_tree_equal (max1, max2)) - return false; - - return true; -} - -/* Compare the relative position of T1 and T2 into their respective - template parameter list. - T1 and T2 must be template parameter types. - Return TRUE if T1 and T2 have the same position, FALSE otherwise. */ - -static bool -comp_template_parms_position (tree t1, tree t2) -{ - tree index1, index2; - gcc_assert (t1 && t2 - && TREE_CODE (t1) == TREE_CODE (t2) - && (TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM - || TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM - || TREE_CODE (t1) == TEMPLATE_TYPE_PARM)); - - index1 = TEMPLATE_TYPE_PARM_INDEX (TYPE_MAIN_VARIANT (t1)); - index2 = TEMPLATE_TYPE_PARM_INDEX (TYPE_MAIN_VARIANT (t2)); - - /* Then compare their relative position. */ - if (TEMPLATE_PARM_IDX (index1) != TEMPLATE_PARM_IDX (index2) - || TEMPLATE_PARM_LEVEL (index1) != TEMPLATE_PARM_LEVEL (index2) - || (TEMPLATE_PARM_PARAMETER_PACK (index1) - != TEMPLATE_PARM_PARAMETER_PACK (index2))) - return false; - - return true; -} - -/* Subroutine in comptypes. */ - -static bool -structural_comptypes (tree t1, tree t2, int strict) -{ - if (t1 == t2) - return true; - - /* Suppress errors caused by previously reported errors. */ - if (t1 == error_mark_node || t2 == error_mark_node) - return false; - - gcc_assert (TYPE_P (t1) && TYPE_P (t2)); - - /* TYPENAME_TYPEs should be resolved if the qualifying scope is the - current instantiation. */ - if (TREE_CODE (t1) == TYPENAME_TYPE) - t1 = resolve_typename_type (t1, /*only_current_p=*/true); - - if (TREE_CODE (t2) == TYPENAME_TYPE) - t2 = resolve_typename_type (t2, /*only_current_p=*/true); - - if (TYPE_PTRMEMFUNC_P (t1)) - t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1); - if (TYPE_PTRMEMFUNC_P (t2)) - t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2); - - /* Different classes of types can't be compatible. */ - if (TREE_CODE (t1) != TREE_CODE (t2)) - return false; - - /* Qualifiers must match. For array types, we will check when we - recur on the array element types. */ - if (TREE_CODE (t1) != ARRAY_TYPE - && cp_type_quals (t1) != cp_type_quals (t2)) - return false; - if (TREE_CODE (t1) == FUNCTION_TYPE - && type_memfn_quals (t1) != type_memfn_quals (t2)) - return false; - /* Need to check this before TYPE_MAIN_VARIANT. - FIXME function qualifiers should really change the main variant. */ - if ((TREE_CODE (t1) == FUNCTION_TYPE - || TREE_CODE (t1) == METHOD_TYPE) - && type_memfn_rqual (t1) != type_memfn_rqual (t2)) - return false; - if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2)) - return false; - - /* Allow for two different type nodes which have essentially the same - definition. Note that we already checked for equality of the type - qualifiers (just above). */ - - if (TREE_CODE (t1) != ARRAY_TYPE - && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2)) - return true; - - - /* Compare the types. Break out if they could be the same. */ - switch (TREE_CODE (t1)) - { - case VOID_TYPE: - case BOOLEAN_TYPE: - /* All void and bool types are the same. */ - break; - - case INTEGER_TYPE: - case FIXED_POINT_TYPE: - case REAL_TYPE: - /* With these nodes, we can't determine type equivalence by - looking at what is stored in the nodes themselves, because - two nodes might have different TYPE_MAIN_VARIANTs but still - represent the same type. For example, wchar_t and int could - have the same properties (TYPE_PRECISION, TYPE_MIN_VALUE, - TYPE_MAX_VALUE, etc.), but have different TYPE_MAIN_VARIANTs - and are distinct types. On the other hand, int and the - following typedef - - typedef int INT __attribute((may_alias)); - - have identical properties, different TYPE_MAIN_VARIANTs, but - represent the same type. The canonical type system keeps - track of equivalence in this case, so we fall back on it. */ - return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2); - - case TEMPLATE_TEMPLATE_PARM: - case BOUND_TEMPLATE_TEMPLATE_PARM: - if (!comp_template_parms_position (t1, t2)) - return false; - if (!comp_template_parms - (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)), - DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2)))) - return false; - if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM) - break; - /* Don't check inheritance. */ - strict = COMPARE_STRICT; - /* Fall through. */ - - case RECORD_TYPE: - case UNION_TYPE: - if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2) - && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2) - || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM) - && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2))) - break; - - if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2)) - break; - else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1)) - break; - - return false; - - case OFFSET_TYPE: - if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2), - strict & ~COMPARE_REDECLARATION)) - return false; - if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2))) - return false; - break; - - case REFERENCE_TYPE: - if (TYPE_REF_IS_RVALUE (t1) != TYPE_REF_IS_RVALUE (t2)) - return false; - /* fall through to checks for pointer types */ - - case POINTER_TYPE: - if (TYPE_MODE (t1) != TYPE_MODE (t2) - || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2) - || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2))) - return false; - break; - - case METHOD_TYPE: - case FUNCTION_TYPE: - if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2))) - return false; - if (!compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2))) - return false; - break; - - case ARRAY_TYPE: - /* Target types must match incl. qualifiers. */ - if (!comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION))) - return false; - break; - - case TEMPLATE_TYPE_PARM: - /* If T1 and T2 don't have the same relative position in their - template parameters set, they can't be equal. */ - if (!comp_template_parms_position (t1, t2)) - return false; - break; - - case TYPENAME_TYPE: - if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1), - TYPENAME_TYPE_FULLNAME (t2))) - return false; - /* Qualifiers don't matter on scopes. */ - if (!same_type_ignoring_top_level_qualifiers_p (TYPE_CONTEXT (t1), - TYPE_CONTEXT (t2))) - return false; - break; - - case UNBOUND_CLASS_TEMPLATE: - if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2))) - return false; - if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2))) - return false; - break; - - case COMPLEX_TYPE: - if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2))) - return false; - break; - - case VECTOR_TYPE: - if (TYPE_VECTOR_SUBPARTS (t1) != TYPE_VECTOR_SUBPARTS (t2) - || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2))) - return false; - break; - - case TYPE_PACK_EXPANSION: - return (same_type_p (PACK_EXPANSION_PATTERN (t1), - PACK_EXPANSION_PATTERN (t2)) - && comp_template_args (PACK_EXPANSION_EXTRA_ARGS (t1), - PACK_EXPANSION_EXTRA_ARGS (t2))); - - case DECLTYPE_TYPE: - if (DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t1) - != DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t2) - || (DECLTYPE_FOR_LAMBDA_CAPTURE (t1) - != DECLTYPE_FOR_LAMBDA_CAPTURE (t2)) - || (DECLTYPE_FOR_LAMBDA_PROXY (t1) - != DECLTYPE_FOR_LAMBDA_PROXY (t2)) - || !cp_tree_equal (DECLTYPE_TYPE_EXPR (t1), - DECLTYPE_TYPE_EXPR (t2))) - return false; - break; - - case UNDERLYING_TYPE: - return same_type_p (UNDERLYING_TYPE_TYPE (t1), - UNDERLYING_TYPE_TYPE (t2)); - - default: - return false; - } - - /* If we get here, we know that from a target independent POV the - types are the same. Make sure the target attributes are also - the same. */ - return comp_type_attributes (t1, t2); -} - -/* Return true if T1 and T2 are related as allowed by STRICT. STRICT - is a bitwise-or of the COMPARE_* flags. */ - -bool -comptypes (tree t1, tree t2, int strict) -{ - if (strict == COMPARE_STRICT) - { - if (t1 == t2) - return true; - - if (t1 == error_mark_node || t2 == error_mark_node) - return false; - - if (TYPE_STRUCTURAL_EQUALITY_P (t1) || TYPE_STRUCTURAL_EQUALITY_P (t2)) - /* At least one of the types requires structural equality, so - perform a deep check. */ - return structural_comptypes (t1, t2, strict); - -#ifdef ENABLE_CHECKING - if (USE_CANONICAL_TYPES) - { - bool result = structural_comptypes (t1, t2, strict); - - if (result && TYPE_CANONICAL (t1) != TYPE_CANONICAL (t2)) - /* The two types are structurally equivalent, but their - canonical types were different. This is a failure of the - canonical type propagation code.*/ - internal_error - ("canonical types differ for identical types %T and %T", - t1, t2); - else if (!result && TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2)) - /* Two types are structurally different, but the canonical - types are the same. This means we were over-eager in - assigning canonical types. */ - internal_error - ("same canonical type node for different types %T and %T", - t1, t2); - - return result; - } -#else - if (USE_CANONICAL_TYPES) - return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2); -#endif - else - return structural_comptypes (t1, t2, strict); - } - else if (strict == COMPARE_STRUCTURAL) - return structural_comptypes (t1, t2, COMPARE_STRICT); - else - return structural_comptypes (t1, t2, strict); -} - -/* Returns nonzero iff TYPE1 and TYPE2 are the same type, ignoring - top-level qualifiers. */ - -bool -same_type_ignoring_top_level_qualifiers_p (tree type1, tree type2) -{ - if (type1 == error_mark_node || type2 == error_mark_node) - return false; - - return same_type_p (TYPE_MAIN_VARIANT (type1), TYPE_MAIN_VARIANT (type2)); -} - -/* Returns 1 if TYPE1 is at least as qualified as TYPE2. */ - -bool -at_least_as_qualified_p (const_tree type1, const_tree type2) -{ - int q1 = cp_type_quals (type1); - int q2 = cp_type_quals (type2); - - /* All qualifiers for TYPE2 must also appear in TYPE1. */ - return (q1 & q2) == q2; -} - -/* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is - more cv-qualified that TYPE1, and 0 otherwise. */ - -int -comp_cv_qualification (const_tree type1, const_tree type2) -{ - int q1 = cp_type_quals (type1); - int q2 = cp_type_quals (type2); - - if (q1 == q2) - return 0; - - if ((q1 & q2) == q2) - return 1; - else if ((q1 & q2) == q1) - return -1; - - return 0; -} - -/* Returns 1 if the cv-qualification signature of TYPE1 is a proper - subset of the cv-qualification signature of TYPE2, and the types - are similar. Returns -1 if the other way 'round, and 0 otherwise. */ - -int -comp_cv_qual_signature (tree type1, tree type2) -{ - if (comp_ptr_ttypes_real (type2, type1, -1)) - return 1; - else if (comp_ptr_ttypes_real (type1, type2, -1)) - return -1; - else - return 0; -} - -/* Subroutines of `comptypes'. */ - -/* Return true if two parameter type lists PARMS1 and PARMS2 are - equivalent in the sense that functions with those parameter types - can have equivalent types. The two lists must be equivalent, - element by element. */ - -bool -compparms (const_tree parms1, const_tree parms2) -{ - const_tree t1, t2; - - /* An unspecified parmlist matches any specified parmlist - whose argument types don't need default promotions. */ - - for (t1 = parms1, t2 = parms2; - t1 || t2; - t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2)) - { - /* If one parmlist is shorter than the other, - they fail to match. */ - if (!t1 || !t2) - return false; - if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2))) - return false; - } - return true; -} - - -/* Process a sizeof or alignof expression where the operand is a - type. */ - -tree -cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain) -{ - tree value; - bool dependent_p; - - gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR); - if (type == error_mark_node) - return error_mark_node; - - type = non_reference (type); - if (TREE_CODE (type) == METHOD_TYPE) - { - if (complain) - pedwarn (input_location, pedantic ? OPT_Wpedantic : OPT_Wpointer_arith, - "invalid application of %qs to a member function", - operator_name_info[(int) op].name); - value = size_one_node; - } - - dependent_p = dependent_type_p (type); - if (!dependent_p) - complete_type (type); - if (dependent_p - /* VLA types will have a non-constant size. In the body of an - uninstantiated template, we don't need to try to compute the - value, because the sizeof expression is not an integral - constant expression in that case. And, if we do try to - compute the value, we'll likely end up with SAVE_EXPRs, which - the template substitution machinery does not expect to see. */ - || (processing_template_decl - && COMPLETE_TYPE_P (type) - && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)) - { - value = build_min (op, size_type_node, type); - TREE_READONLY (value) = 1; - return value; - } - - return c_sizeof_or_alignof_type (input_location, complete_type (type), - op == SIZEOF_EXPR, - complain); -} - -/* Return the size of the type, without producing any warnings for - types whose size cannot be taken. This routine should be used only - in some other routine that has already produced a diagnostic about - using the size of such a type. */ -tree -cxx_sizeof_nowarn (tree type) -{ - if (TREE_CODE (type) == FUNCTION_TYPE - || TREE_CODE (type) == VOID_TYPE - || TREE_CODE (type) == ERROR_MARK) - return size_one_node; - else if (!COMPLETE_TYPE_P (type)) - return size_zero_node; - else - return cxx_sizeof_or_alignof_type (type, SIZEOF_EXPR, false); -} - -/* Process a sizeof expression where the operand is an expression. */ - -static tree -cxx_sizeof_expr (tree e, tsubst_flags_t complain) -{ - if (e == error_mark_node) - return error_mark_node; - - if (processing_template_decl) - { - e = build_min (SIZEOF_EXPR, size_type_node, e); - TREE_SIDE_EFFECTS (e) = 0; - TREE_READONLY (e) = 1; - - return e; - } - - /* To get the size of a static data member declared as an array of - unknown bound, we need to instantiate it. */ - if (TREE_CODE (e) == VAR_DECL - && VAR_HAD_UNKNOWN_BOUND (e) - && DECL_TEMPLATE_INSTANTIATION (e)) - instantiate_decl (e, /*defer_ok*/true, /*expl_inst_mem*/false); - - e = mark_type_use (e); - - if (TREE_CODE (e) == COMPONENT_REF - && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL - && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1))) - { - if (complain & tf_error) - error ("invalid application of %<sizeof%> to a bit-field"); - else - return error_mark_node; - e = char_type_node; - } - else if (is_overloaded_fn (e)) - { - if (complain & tf_error) - permerror (input_location, "ISO C++ forbids applying %<sizeof%> to an expression of " - "function type"); - else - return error_mark_node; - e = char_type_node; - } - else if (type_unknown_p (e)) - { - if (complain & tf_error) - cxx_incomplete_type_error (e, TREE_TYPE (e)); - else - return error_mark_node; - e = char_type_node; - } - else - e = TREE_TYPE (e); - - return cxx_sizeof_or_alignof_type (e, SIZEOF_EXPR, complain & tf_error); -} - -/* Implement the __alignof keyword: Return the minimum required - alignment of E, measured in bytes. For VAR_DECL's and - FIELD_DECL's return DECL_ALIGN (which can be set from an - "aligned" __attribute__ specification). */ - -static tree -cxx_alignof_expr (tree e, tsubst_flags_t complain) -{ - tree t; - - if (e == error_mark_node) - return error_mark_node; - - if (processing_template_decl) - { - e = build_min (ALIGNOF_EXPR, size_type_node, e); - TREE_SIDE_EFFECTS (e) = 0; - TREE_READONLY (e) = 1; - - return e; - } - - e = mark_type_use (e); - - if (TREE_CODE (e) == VAR_DECL) - t = size_int (DECL_ALIGN_UNIT (e)); - else if (TREE_CODE (e) == COMPONENT_REF - && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL - && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1))) - { - if (complain & tf_error) - error ("invalid application of %<__alignof%> to a bit-field"); - else - return error_mark_node; - t = size_one_node; - } - else if (TREE_CODE (e) == COMPONENT_REF - && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL) - t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (e, 1))); - else if (is_overloaded_fn (e)) - { - if (complain & tf_error) - permerror (input_location, "ISO C++ forbids applying %<__alignof%> to an expression of " - "function type"); - else - return error_mark_node; - if (TREE_CODE (e) == FUNCTION_DECL) - t = size_int (DECL_ALIGN_UNIT (e)); - else - t = size_one_node; - } - else if (type_unknown_p (e)) - { - if (complain & tf_error) - cxx_incomplete_type_error (e, TREE_TYPE (e)); - else - return error_mark_node; - t = size_one_node; - } - else - return cxx_sizeof_or_alignof_type (TREE_TYPE (e), ALIGNOF_EXPR, - complain & tf_error); - - return fold_convert (size_type_node, t); -} - -/* Process a sizeof or alignof expression E with code OP where the operand - is an expression. */ - -tree -cxx_sizeof_or_alignof_expr (tree e, enum tree_code op, bool complain) -{ - if (op == SIZEOF_EXPR) - return cxx_sizeof_expr (e, complain? tf_warning_or_error : tf_none); - else - return cxx_alignof_expr (e, complain? tf_warning_or_error : tf_none); -} - -/* Build a representation of an expression 'alignas(E).' Return the - folded integer value of E if it is an integral constant expression - that resolves to a valid alignment. If E depends on a template - parameter, return a syntactic representation tree of kind - ALIGNOF_EXPR. Otherwise, return an error_mark_node if the - expression is ill formed, or NULL_TREE if E is NULL_TREE. */ - -tree -cxx_alignas_expr (tree e) -{ - if (e == NULL_TREE || e == error_mark_node - || (!TYPE_P (e) && !require_potential_rvalue_constant_expression (e))) - return e; - - if (TYPE_P (e)) - /* [dcl.align]/3: - - When the alignment-specifier is of the form - alignas(type-id ), it shall have the same effect as - alignas(alignof(type-id )). */ - - return cxx_sizeof_or_alignof_type (e, ALIGNOF_EXPR, false); - - /* If we reach this point, it means the alignas expression if of - the form "alignas(assignment-expression)", so we should follow - what is stated by [dcl.align]/2. */ - - if (value_dependent_expression_p (e)) - /* Leave value-dependent expression alone for now. */ - return e; - - e = fold_non_dependent_expr (e); - e = mark_rvalue_use (e); - - /* [dcl.align]/2 says: - - the assignment-expression shall be an integral constant - expression. */ - - return cxx_constant_value (e); -} - - -/* EXPR is being used in a context that is not a function call. - Enforce: - - [expr.ref] - - The expression can be used only as the left-hand operand of a - member function call. - - [expr.mptr.operator] - - If the result of .* or ->* is a function, then that result can be - used only as the operand for the function call operator (). - - by issuing an error message if appropriate. Returns true iff EXPR - violates these rules. */ - -bool -invalid_nonstatic_memfn_p (const_tree expr, tsubst_flags_t complain) -{ - if (expr && DECL_NONSTATIC_MEMBER_FUNCTION_P (expr)) - { - if (complain & tf_error) - error ("invalid use of non-static member function"); - return true; - } - return false; -} - -/* If EXP is a reference to a bitfield, and the type of EXP does not - match the declared type of the bitfield, return the declared type - of the bitfield. Otherwise, return NULL_TREE. */ - -tree -is_bitfield_expr_with_lowered_type (const_tree exp) -{ - switch (TREE_CODE (exp)) - { - case COND_EXPR: - if (!is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1) - ? TREE_OPERAND (exp, 1) - : TREE_OPERAND (exp, 0))) - return NULL_TREE; - return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 2)); - - case COMPOUND_EXPR: - return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1)); - - case MODIFY_EXPR: - case SAVE_EXPR: - return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0)); - - case COMPONENT_REF: - { - tree field; - - field = TREE_OPERAND (exp, 1); - if (TREE_CODE (field) != FIELD_DECL || !DECL_BIT_FIELD_TYPE (field)) - return NULL_TREE; - if (same_type_ignoring_top_level_qualifiers_p - (TREE_TYPE (exp), DECL_BIT_FIELD_TYPE (field))) - return NULL_TREE; - return DECL_BIT_FIELD_TYPE (field); - } - - CASE_CONVERT: - if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (exp, 0))) - == TYPE_MAIN_VARIANT (TREE_TYPE (exp))) - return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0)); - /* Fallthrough. */ - - default: - return NULL_TREE; - } -} - -/* Like is_bitfield_with_lowered_type, except that if EXP is not a - bitfield with a lowered type, the type of EXP is returned, rather - than NULL_TREE. */ - -tree -unlowered_expr_type (const_tree exp) -{ - tree type; - tree etype = TREE_TYPE (exp); - - type = is_bitfield_expr_with_lowered_type (exp); - if (type) - type = cp_build_qualified_type (type, cp_type_quals (etype)); - else - type = etype; - - return type; -} - -/* Perform the conversions in [expr] that apply when an lvalue appears - in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and - function-to-pointer conversions. In addition, manifest constants - are replaced by their values, and bitfield references are converted - to their declared types. Note that this function does not perform the - lvalue-to-rvalue conversion for class types. If you need that conversion - to for class types, then you probably need to use force_rvalue. - - Although the returned value is being used as an rvalue, this - function does not wrap the returned expression in a - NON_LVALUE_EXPR; the caller is expected to be mindful of the fact - that the return value is no longer an lvalue. */ - -tree -decay_conversion (tree exp, tsubst_flags_t complain) -{ - tree type; - enum tree_code code; - location_t loc = EXPR_LOC_OR_HERE (exp); - - type = TREE_TYPE (exp); - if (type == error_mark_node) - return error_mark_node; - - exp = mark_rvalue_use (exp); - - exp = resolve_nondeduced_context (exp); - if (type_unknown_p (exp)) - { - if (complain & tf_error) - cxx_incomplete_type_error (exp, TREE_TYPE (exp)); - return error_mark_node; - } - - code = TREE_CODE (type); - - /* For an array decl decay_conversion should not try to return its - initializer. */ - if (code != ARRAY_TYPE) - { - /* FIXME remove? at least need to remember that this isn't really a - constant expression if EXP isn't decl_constant_var_p, like with - C_MAYBE_CONST_EXPR. */ - exp = decl_constant_value_safe (exp); - if (error_operand_p (exp)) - return error_mark_node; - } - - if (NULLPTR_TYPE_P (type) && !TREE_SIDE_EFFECTS (exp)) - return nullptr_node; - - /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue. - Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */ - if (code == VOID_TYPE) - { - if (complain & tf_error) - error_at (loc, "void value not ignored as it ought to be"); - return error_mark_node; - } - if (invalid_nonstatic_memfn_p (exp, complain)) - return error_mark_node; - if (code == FUNCTION_TYPE || is_overloaded_fn (exp)) - return cp_build_addr_expr (exp, complain); - if (code == ARRAY_TYPE) - { - tree adr; - tree ptrtype; - - if (TREE_CODE (exp) == INDIRECT_REF) - return build_nop (build_pointer_type (TREE_TYPE (type)), - TREE_OPERAND (exp, 0)); - - if (TREE_CODE (exp) == COMPOUND_EXPR) - { - tree op1 = decay_conversion (TREE_OPERAND (exp, 1), complain); - if (op1 == error_mark_node) - return error_mark_node; - return build2 (COMPOUND_EXPR, TREE_TYPE (op1), - TREE_OPERAND (exp, 0), op1); - } - - if (!lvalue_p (exp) - && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp))) - { - if (complain & tf_error) - error_at (loc, "invalid use of non-lvalue array"); - return error_mark_node; - } - - /* Don't let an array compound literal decay to a pointer. It can - still be used to initialize an array or bind to a reference. */ - if (TREE_CODE (exp) == TARGET_EXPR) - { - if (complain & tf_error) - error_at (loc, "taking address of temporary array"); - return error_mark_node; - } - - ptrtype = build_pointer_type (TREE_TYPE (type)); - - if (TREE_CODE (exp) == VAR_DECL) - { - if (!cxx_mark_addressable (exp)) - return error_mark_node; - adr = build_nop (ptrtype, build_address (exp)); - return adr; - } - /* This way is better for a COMPONENT_REF since it can - simplify the offset for a component. */ - adr = cp_build_addr_expr (exp, complain); - return cp_convert (ptrtype, adr, complain); - } - - /* If a bitfield is used in a context where integral promotion - applies, then the caller is expected to have used - default_conversion. That function promotes bitfields correctly - before calling this function. At this point, if we have a - bitfield referenced, we may assume that is not subject to - promotion, and that, therefore, the type of the resulting rvalue - is the declared type of the bitfield. */ - exp = convert_bitfield_to_declared_type (exp); - - /* We do not call rvalue() here because we do not want to wrap EXP - in a NON_LVALUE_EXPR. */ - - /* [basic.lval] - - Non-class rvalues always have cv-unqualified types. */ - type = TREE_TYPE (exp); - if (!CLASS_TYPE_P (type) && cv_qualified_p (type)) - exp = build_nop (cv_unqualified (type), exp); - - return exp; -} - -/* Perform preparatory conversions, as part of the "usual arithmetic - conversions". In particular, as per [expr]: - - Whenever an lvalue expression appears as an operand of an - operator that expects the rvalue for that operand, the - lvalue-to-rvalue, array-to-pointer, or function-to-pointer - standard conversions are applied to convert the expression to an - rvalue. - - In addition, we perform integral promotions here, as those are - applied to both operands to a binary operator before determining - what additional conversions should apply. */ - -static tree -cp_default_conversion (tree exp, tsubst_flags_t complain) -{ - /* Check for target-specific promotions. */ - tree promoted_type = targetm.promoted_type (TREE_TYPE (exp)); - if (promoted_type) - exp = cp_convert (promoted_type, exp, complain); - /* Perform the integral promotions first so that bitfield - expressions (which may promote to "int", even if the bitfield is - declared "unsigned") are promoted correctly. */ - else if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (exp))) - exp = cp_perform_integral_promotions (exp, complain); - /* Perform the other conversions. */ - exp = decay_conversion (exp, complain); - - return exp; -} - -/* C version. */ - -tree -default_conversion (tree exp) -{ - return cp_default_conversion (exp, tf_warning_or_error); -} - -/* EXPR is an expression with an integral or enumeration type. - Perform the integral promotions in [conv.prom], and return the - converted value. */ - -tree -cp_perform_integral_promotions (tree expr, tsubst_flags_t complain) -{ - tree type; - tree promoted_type; - - expr = mark_rvalue_use (expr); - - /* [conv.prom] - - If the bitfield has an enumerated type, it is treated as any - other value of that type for promotion purposes. */ - type = is_bitfield_expr_with_lowered_type (expr); - if (!type || TREE_CODE (type) != ENUMERAL_TYPE) - type = TREE_TYPE (expr); - gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type)); - /* Scoped enums don't promote. */ - if (SCOPED_ENUM_P (type)) - return expr; - promoted_type = type_promotes_to (type); - if (type != promoted_type) - expr = cp_convert (promoted_type, expr, complain); - return expr; -} - -/* C version. */ - -tree -perform_integral_promotions (tree expr) -{ - return cp_perform_integral_promotions (expr, tf_warning_or_error); -} - -/* Returns nonzero iff exp is a STRING_CST or the result of applying - decay_conversion to one. */ - -int -string_conv_p (const_tree totype, const_tree exp, int warn) -{ - tree t; - - if (TREE_CODE (totype) != POINTER_TYPE) - return 0; - - t = TREE_TYPE (totype); - if (!same_type_p (t, char_type_node) - && !same_type_p (t, char16_type_node) - && !same_type_p (t, char32_type_node) - && !same_type_p (t, wchar_type_node)) - return 0; - - if (TREE_CODE (exp) == STRING_CST) - { - /* Make sure that we don't try to convert between char and wide chars. */ - if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t)) - return 0; - } - else - { - /* Is this a string constant which has decayed to 'const char *'? */ - t = build_pointer_type (cp_build_qualified_type (t, TYPE_QUAL_CONST)); - if (!same_type_p (TREE_TYPE (exp), t)) - return 0; - STRIP_NOPS (exp); - if (TREE_CODE (exp) != ADDR_EXPR - || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST) - return 0; - } - - /* This warning is not very useful, as it complains about printf. */ - if (warn) - warning (OPT_Wwrite_strings, - "deprecated conversion from string constant to %qT", - totype); - - return 1; -} - -/* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we - can, for example, use as an lvalue. This code used to be in - unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c' - expressions, where we're dealing with aggregates. But now it's again only - called from unary_complex_lvalue. The case (in particular) that led to - this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd - get it there. */ - -static tree -rationalize_conditional_expr (enum tree_code code, tree t, - tsubst_flags_t complain) -{ - /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that - the first operand is always the one to be used if both operands - are equal, so we know what conditional expression this used to be. */ - if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR) - { - tree op0 = TREE_OPERAND (t, 0); - tree op1 = TREE_OPERAND (t, 1); - - /* The following code is incorrect if either operand side-effects. */ - gcc_assert (!TREE_SIDE_EFFECTS (op0) - && !TREE_SIDE_EFFECTS (op1)); - return - build_conditional_expr (build_x_binary_op (input_location, - (TREE_CODE (t) == MIN_EXPR - ? LE_EXPR : GE_EXPR), - op0, TREE_CODE (op0), - op1, TREE_CODE (op1), - /*overload=*/NULL, - complain), - cp_build_unary_op (code, op0, 0, complain), - cp_build_unary_op (code, op1, 0, complain), - complain); - } - - return - build_conditional_expr (TREE_OPERAND (t, 0), - cp_build_unary_op (code, TREE_OPERAND (t, 1), 0, - complain), - cp_build_unary_op (code, TREE_OPERAND (t, 2), 0, - complain), - complain); -} - -/* Given the TYPE of an anonymous union field inside T, return the - FIELD_DECL for the field. If not found return NULL_TREE. Because - anonymous unions can nest, we must also search all anonymous unions - that are directly reachable. */ - -tree -lookup_anon_field (tree t, tree type) -{ - tree field; - - for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field)) - { - if (TREE_STATIC (field)) - continue; - if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field)) - continue; - - /* If we find it directly, return the field. */ - if (DECL_NAME (field) == NULL_TREE - && type == TYPE_MAIN_VARIANT (TREE_TYPE (field))) - { - return field; - } - - /* Otherwise, it could be nested, search harder. */ - if (DECL_NAME (field) == NULL_TREE - && ANON_AGGR_TYPE_P (TREE_TYPE (field))) - { - tree subfield = lookup_anon_field (TREE_TYPE (field), type); - if (subfield) - return subfield; - } - } - return NULL_TREE; -} - -/* Build an expression representing OBJECT.MEMBER. OBJECT is an - expression; MEMBER is a DECL or baselink. If ACCESS_PATH is - non-NULL, it indicates the path to the base used to name MEMBER. - If PRESERVE_REFERENCE is true, the expression returned will have - REFERENCE_TYPE if the MEMBER does. Otherwise, the expression - returned will have the type referred to by the reference. - - This function does not perform access control; that is either done - earlier by the parser when the name of MEMBER is resolved to MEMBER - itself, or later when overload resolution selects one of the - functions indicated by MEMBER. */ - -tree -build_class_member_access_expr (tree object, tree member, - tree access_path, bool preserve_reference, - tsubst_flags_t complain) -{ - tree object_type; - tree member_scope; - tree result = NULL_TREE; - tree using_decl = NULL_TREE; - - if (error_operand_p (object) || error_operand_p (member)) - return error_mark_node; - - gcc_assert (DECL_P (member) || BASELINK_P (member)); - - /* [expr.ref] - - The type of the first expression shall be "class object" (of a - complete type). */ - object_type = TREE_TYPE (object); - if (!currently_open_class (object_type) - && !complete_type_or_maybe_complain (object_type, object, complain)) - return error_mark_node; - if (!CLASS_TYPE_P (object_type)) - { - if (complain & tf_error) - { - if (POINTER_TYPE_P (object_type) - && CLASS_TYPE_P (TREE_TYPE (object_type))) - error ("request for member %qD in %qE, which is of pointer " - "type %qT (maybe you meant to use %<->%> ?)", - member, object, object_type); - else - error ("request for member %qD in %qE, which is of non-class " - "type %qT", member, object, object_type); - } - return error_mark_node; - } - - /* The standard does not seem to actually say that MEMBER must be a - member of OBJECT_TYPE. However, that is clearly what is - intended. */ - if (DECL_P (member)) - { - member_scope = DECL_CLASS_CONTEXT (member); - mark_used (member); - if (TREE_DEPRECATED (member)) - warn_deprecated_use (member, NULL_TREE); - } - else - member_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (member)); - /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will - presently be the anonymous union. Go outwards until we find a - type related to OBJECT_TYPE. */ - while ((ANON_AGGR_TYPE_P (member_scope) || UNSCOPED_ENUM_P (member_scope)) - && !same_type_ignoring_top_level_qualifiers_p (member_scope, - object_type)) - member_scope = TYPE_CONTEXT (member_scope); - if (!member_scope || !DERIVED_FROM_P (member_scope, object_type)) - { - if (complain & tf_error) - { - if (TREE_CODE (member) == FIELD_DECL) - error ("invalid use of nonstatic data member %qE", member); - else - error ("%qD is not a member of %qT", member, object_type); - } - return error_mark_node; - } - - /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into - `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue - in the front end; only _DECLs and _REFs are lvalues in the back end. */ - { - tree temp = unary_complex_lvalue (ADDR_EXPR, object); - if (temp) - object = cp_build_indirect_ref (temp, RO_NULL, complain); - } - - /* In [expr.ref], there is an explicit list of the valid choices for - MEMBER. We check for each of those cases here. */ - if (TREE_CODE (member) == VAR_DECL) - { - /* A static data member. */ - result = member; - mark_exp_read (object); - /* If OBJECT has side-effects, they are supposed to occur. */ - if (TREE_SIDE_EFFECTS (object)) - result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result); - } - else if (TREE_CODE (member) == FIELD_DECL) - { - /* A non-static data member. */ - bool null_object_p; - int type_quals; - tree member_type; - - null_object_p = (TREE_CODE (object) == INDIRECT_REF - && integer_zerop (TREE_OPERAND (object, 0))); - - /* Convert OBJECT to the type of MEMBER. */ - if (!same_type_p (TYPE_MAIN_VARIANT (object_type), - TYPE_MAIN_VARIANT (member_scope))) - { - tree binfo; - base_kind kind; - - binfo = lookup_base (access_path ? access_path : object_type, - member_scope, ba_unique, &kind, complain); - if (binfo == error_mark_node) - return error_mark_node; - - /* It is invalid to try to get to a virtual base of a - NULL object. The most common cause is invalid use of - offsetof macro. */ - if (null_object_p && kind == bk_via_virtual) - { - if (complain & tf_error) - { - error ("invalid access to non-static data member %qD of " - "NULL object", - member); - error ("(perhaps the %<offsetof%> macro was used incorrectly)"); - } - return error_mark_node; - } - - /* Convert to the base. */ - object = build_base_path (PLUS_EXPR, object, binfo, - /*nonnull=*/1, complain); - /* If we found the base successfully then we should be able - to convert to it successfully. */ - gcc_assert (object != error_mark_node); - } - - /* Complain about other invalid uses of offsetof, even though they will - give the right answer. Note that we complain whether or not they - actually used the offsetof macro, since there's no way to know at this - point. So we just give a warning, instead of a pedwarn. */ - /* Do not produce this warning for base class field references, because - we know for a fact that didn't come from offsetof. This does occur - in various testsuite cases where a null object is passed where a - vtable access is required. */ - if (null_object_p && warn_invalid_offsetof - && CLASSTYPE_NON_STD_LAYOUT (object_type) - && !DECL_FIELD_IS_BASE (member) - && cp_unevaluated_operand == 0 - && (complain & tf_warning)) - { - warning (OPT_Winvalid_offsetof, - "invalid access to non-static data member %qD " - " of NULL object", member); - warning (OPT_Winvalid_offsetof, - "(perhaps the %<offsetof%> macro was used incorrectly)"); - } - - /* If MEMBER is from an anonymous aggregate, we have converted - OBJECT so that it refers to the class containing the - anonymous union. Generate a reference to the anonymous union - itself, and recur to find MEMBER. */ - if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member)) - /* When this code is called from build_field_call, the - object already has the type of the anonymous union. - That is because the COMPONENT_REF was already - constructed, and was then disassembled before calling - build_field_call. After the function-call code is - cleaned up, this waste can be eliminated. */ - && (!same_type_ignoring_top_level_qualifiers_p - (TREE_TYPE (object), DECL_CONTEXT (member)))) - { - tree anonymous_union; - - anonymous_union = lookup_anon_field (TREE_TYPE (object), - DECL_CONTEXT (member)); - object = build_class_member_access_expr (object, - anonymous_union, - /*access_path=*/NULL_TREE, - preserve_reference, - complain); - } - - /* Compute the type of the field, as described in [expr.ref]. */ - type_quals = TYPE_UNQUALIFIED; - member_type = TREE_TYPE (member); - if (TREE_CODE (member_type) != REFERENCE_TYPE) - { - type_quals = (cp_type_quals (member_type) - | cp_type_quals (object_type)); - - /* A field is const (volatile) if the enclosing object, or the - field itself, is const (volatile). But, a mutable field is - not const, even within a const object. */ - if (DECL_MUTABLE_P (member)) - type_quals &= ~TYPE_QUAL_CONST; - member_type = cp_build_qualified_type (member_type, type_quals); - } - - result = build3 (COMPONENT_REF, member_type, object, member, - NULL_TREE); - result = fold_if_not_in_template (result); - - /* Mark the expression const or volatile, as appropriate. Even - though we've dealt with the type above, we still have to mark the - expression itself. */ - if (type_quals & TYPE_QUAL_CONST) - TREE_READONLY (result) = 1; - if (type_quals & TYPE_QUAL_VOLATILE) - TREE_THIS_VOLATILE (result) = 1; - } - else if (BASELINK_P (member)) - { - /* The member is a (possibly overloaded) member function. */ - tree functions; - tree type; - - /* If the MEMBER is exactly one static member function, then we - know the type of the expression. Otherwise, we must wait - until overload resolution has been performed. */ - functions = BASELINK_FUNCTIONS (member); - if (TREE_CODE (functions) == FUNCTION_DECL - && DECL_STATIC_FUNCTION_P (functions)) - type = TREE_TYPE (functions); - else - type = unknown_type_node; - /* Note that we do not convert OBJECT to the BASELINK_BINFO - base. That will happen when the function is called. */ - result = build3 (COMPONENT_REF, type, object, member, NULL_TREE); - } - else if (TREE_CODE (member) == CONST_DECL) - { - /* The member is an enumerator. */ - result = member; - /* If OBJECT has side-effects, they are supposed to occur. */ - if (TREE_SIDE_EFFECTS (object)) - result = build2 (COMPOUND_EXPR, TREE_TYPE (result), - object, result); - } - else if ((using_decl = strip_using_decl (member)) != member) - result = build_class_member_access_expr (object, - using_decl, - access_path, preserve_reference, - complain); - else - { - if (complain & tf_error) - error ("invalid use of %qD", member); - return error_mark_node; - } - - if (!preserve_reference) - /* [expr.ref] - - If E2 is declared to have type "reference to T", then ... the - type of E1.E2 is T. */ - result = convert_from_reference (result); - - return result; -} - -/* Return the destructor denoted by OBJECT.SCOPE::DTOR_NAME, or, if - SCOPE is NULL, by OBJECT.DTOR_NAME, where DTOR_NAME is ~type. */ - -static tree -lookup_destructor (tree object, tree scope, tree dtor_name) -{ - tree object_type = TREE_TYPE (object); - tree dtor_type = TREE_OPERAND (dtor_name, 0); - tree expr; - - if (scope && !check_dtor_name (scope, dtor_type)) - { - error ("qualified type %qT does not match destructor name ~%qT", - scope, dtor_type); - return error_mark_node; - } - if (TREE_CODE (dtor_type) == IDENTIFIER_NODE) - { - /* In a template, names we can't find a match for are still accepted - destructor names, and we check them here. */ - if (check_dtor_name (object_type, dtor_type)) - dtor_type = object_type; - else - { - error ("object type %qT does not match destructor name ~%qT", - object_type, dtor_type); - return error_mark_node; - } - - } - else if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type))) - { - error ("the type being destroyed is %qT, but the destructor refers to %qT", - TYPE_MAIN_VARIANT (object_type), dtor_type); - return error_mark_node; - } - expr = lookup_member (dtor_type, complete_dtor_identifier, - /*protect=*/1, /*want_type=*/false, - tf_warning_or_error); - expr = (adjust_result_of_qualified_name_lookup - (expr, dtor_type, object_type)); - if (scope == NULL_TREE) - /* We need to call adjust_result_of_qualified_name_lookup in case the - destructor names a base class, but we unset BASELINK_QUALIFIED_P so - that we still get virtual function binding. */ - BASELINK_QUALIFIED_P (expr) = false; - return expr; -} - -/* An expression of the form "A::template B" has been resolved to - DECL. Issue a diagnostic if B is not a template or template - specialization. */ - -void -check_template_keyword (tree decl) -{ - /* The standard says: - - [temp.names] - - If a name prefixed by the keyword template is not a member - template, the program is ill-formed. - - DR 228 removed the restriction that the template be a member - template. - - DR 96, if accepted would add the further restriction that explicit - template arguments must be provided if the template keyword is - used, but, as of 2005-10-16, that DR is still in "drafting". If - this DR is accepted, then the semantic checks here can be - simplified, as the entity named must in fact be a template - specialization, rather than, as at present, a set of overloaded - functions containing at least one template function. */ - if (TREE_CODE (decl) != TEMPLATE_DECL - && TREE_CODE (decl) != TEMPLATE_ID_EXPR) - { - if (!is_overloaded_fn (decl)) - permerror (input_location, "%qD is not a template", decl); - else - { - tree fns; - fns = decl; - if (BASELINK_P (fns)) - fns = BASELINK_FUNCTIONS (fns); - while (fns) - { - tree fn = OVL_CURRENT (fns); - if (TREE_CODE (fn) == TEMPLATE_DECL - || TREE_CODE (fn) == TEMPLATE_ID_EXPR) - break; - if (TREE_CODE (fn) == FUNCTION_DECL - && DECL_USE_TEMPLATE (fn) - && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn))) - break; - fns = OVL_NEXT (fns); - } - if (!fns) - permerror (input_location, "%qD is not a template", decl); - } - } -} - -/* This function is called by the parser to process a class member - access expression of the form OBJECT.NAME. NAME is a node used by - the parser to represent a name; it is not yet a DECL. It may, - however, be a BASELINK where the BASELINK_FUNCTIONS is a - TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and - there is no reason to do the lookup twice, so the parser keeps the - BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to - be a template via the use of the "A::template B" syntax. */ - -tree -finish_class_member_access_expr (tree object, tree name, bool template_p, - tsubst_flags_t complain) -{ - tree expr; - tree object_type; - tree member; - tree access_path = NULL_TREE; - tree orig_object = object; - tree orig_name = name; - - if (object == error_mark_node || name == error_mark_node) - return error_mark_node; - - /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */ - if (!objc_is_public (object, name)) - return error_mark_node; - - object_type = TREE_TYPE (object); - - if (processing_template_decl) - { - if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */ - dependent_type_p (object_type) - /* If NAME is just an IDENTIFIER_NODE, then the expression - is dependent. */ - || TREE_CODE (object) == IDENTIFIER_NODE - /* If NAME is "f<args>", where either 'f' or 'args' is - dependent, then the expression is dependent. */ - || (TREE_CODE (name) == TEMPLATE_ID_EXPR - && dependent_template_id_p (TREE_OPERAND (name, 0), - TREE_OPERAND (name, 1))) - /* If NAME is "T::X" where "T" is dependent, then the - expression is dependent. */ - || (TREE_CODE (name) == SCOPE_REF - && TYPE_P (TREE_OPERAND (name, 0)) - && dependent_type_p (TREE_OPERAND (name, 0)))) - return build_min_nt_loc (UNKNOWN_LOCATION, COMPONENT_REF, - object, name, NULL_TREE); - object = build_non_dependent_expr (object); - } - else if (c_dialect_objc () - && TREE_CODE (name) == IDENTIFIER_NODE - && (expr = objc_maybe_build_component_ref (object, name))) - return expr; - - /* [expr.ref] - - The type of the first expression shall be "class object" (of a - complete type). */ - if (!currently_open_class (object_type) - && !complete_type_or_maybe_complain (object_type, object, complain)) - return error_mark_node; - if (!CLASS_TYPE_P (object_type)) - { - if (complain & tf_error) - { - if (POINTER_TYPE_P (object_type) - && CLASS_TYPE_P (TREE_TYPE (object_type))) - error ("request for member %qD in %qE, which is of pointer " - "type %qT (maybe you meant to use %<->%> ?)", - name, object, object_type); - else - error ("request for member %qD in %qE, which is of non-class " - "type %qT", name, object, object_type); - } - return error_mark_node; - } - - if (BASELINK_P (name)) - /* A member function that has already been looked up. */ - member = name; - else - { - bool is_template_id = false; - tree template_args = NULL_TREE; - tree scope; - - if (TREE_CODE (name) == TEMPLATE_ID_EXPR) - { - is_template_id = true; - template_args = TREE_OPERAND (name, 1); - name = TREE_OPERAND (name, 0); - - if (TREE_CODE (name) == OVERLOAD) - name = DECL_NAME (get_first_fn (name)); - else if (DECL_P (name)) - name = DECL_NAME (name); - } - - if (TREE_CODE (name) == SCOPE_REF) - { - /* A qualified name. The qualifying class or namespace `S' - has already been looked up; it is either a TYPE or a - NAMESPACE_DECL. */ - scope = TREE_OPERAND (name, 0); - name = TREE_OPERAND (name, 1); - - /* If SCOPE is a namespace, then the qualified name does not - name a member of OBJECT_TYPE. */ - if (TREE_CODE (scope) == NAMESPACE_DECL) - { - if (complain & tf_error) - error ("%<%D::%D%> is not a member of %qT", - scope, name, object_type); - return error_mark_node; - } - - if (TREE_CODE (scope) == ENUMERAL_TYPE) - { - /* Looking up a member enumerator (c++/56793). */ - if (!TYPE_CLASS_SCOPE_P (scope) - || !DERIVED_FROM_P (TYPE_CONTEXT (scope), object_type)) - { - if (complain & tf_error) - error ("%<%D::%D%> is not a member of %qT", - scope, name, object_type); - return error_mark_node; - } - tree val = lookup_enumerator (scope, name); - if (TREE_SIDE_EFFECTS (object)) - val = build2 (COMPOUND_EXPR, TREE_TYPE (val), object, val); - return val; - } - - gcc_assert (CLASS_TYPE_P (scope)); - gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE - || TREE_CODE (name) == BIT_NOT_EXPR); - - if (constructor_name_p (name, scope)) - { - if (complain & tf_error) - error ("cannot call constructor %<%T::%D%> directly", - scope, name); - return error_mark_node; - } - - /* Find the base of OBJECT_TYPE corresponding to SCOPE. */ - access_path = lookup_base (object_type, scope, ba_check, - NULL, complain); - if (access_path == error_mark_node) - return error_mark_node; - if (!access_path) - { - if (complain & tf_error) - error ("%qT is not a base of %qT", scope, object_type); - return error_mark_node; - } - } - else - { - scope = NULL_TREE; - access_path = object_type; - } - - if (TREE_CODE (name) == BIT_NOT_EXPR) - member = lookup_destructor (object, scope, name); - else - { - /* Look up the member. */ - member = lookup_member (access_path, name, /*protect=*/1, - /*want_type=*/false, complain); - if (member == NULL_TREE) - { - if (complain & tf_error) - error ("%qD has no member named %qE", - TREE_CODE (access_path) == TREE_BINFO - ? TREE_TYPE (access_path) : object_type, name); - return error_mark_node; - } - if (member == error_mark_node) - return error_mark_node; - } - - if (is_template_id) - { - tree templ = member; - - if (BASELINK_P (templ)) - templ = lookup_template_function (templ, template_args); - else - { - if (complain & tf_error) - error ("%qD is not a member template function", name); - return error_mark_node; - } - } - } - - if (TREE_DEPRECATED (member)) - warn_deprecated_use (member, NULL_TREE); - - if (template_p) - check_template_keyword (member); - - expr = build_class_member_access_expr (object, member, access_path, - /*preserve_reference=*/false, - complain); - if (processing_template_decl && expr != error_mark_node) - { - if (BASELINK_P (member)) - { - if (TREE_CODE (orig_name) == SCOPE_REF) - BASELINK_QUALIFIED_P (member) = 1; - orig_name = member; - } - return build_min_non_dep (COMPONENT_REF, expr, - orig_object, orig_name, - NULL_TREE); - } - - return expr; -} - -/* Return an expression for the MEMBER_NAME field in the internal - representation of PTRMEM, a pointer-to-member function. (Each - pointer-to-member function type gets its own RECORD_TYPE so it is - more convenient to access the fields by name than by FIELD_DECL.) - This routine converts the NAME to a FIELD_DECL and then creates the - node for the complete expression. */ - -tree -build_ptrmemfunc_access_expr (tree ptrmem, tree member_name) -{ - tree ptrmem_type; - tree member; - tree member_type; - - /* This code is a stripped down version of - build_class_member_access_expr. It does not work to use that - routine directly because it expects the object to be of class - type. */ - ptrmem_type = TREE_TYPE (ptrmem); - gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type)); - member = lookup_member (ptrmem_type, member_name, /*protect=*/0, - /*want_type=*/false, tf_warning_or_error); - member_type = cp_build_qualified_type (TREE_TYPE (member), - cp_type_quals (ptrmem_type)); - return fold_build3_loc (input_location, - COMPONENT_REF, member_type, - ptrmem, member, NULL_TREE); -} - -/* Given an expression PTR for a pointer, return an expression - for the value pointed to. - ERRORSTRING is the name of the operator to appear in error messages. - - This function may need to overload OPERATOR_FNNAME. - Must also handle REFERENCE_TYPEs for C++. */ - -tree -build_x_indirect_ref (location_t loc, tree expr, ref_operator errorstring, - tsubst_flags_t complain) -{ - tree orig_expr = expr; - tree rval; - - if (processing_template_decl) - { - /* Retain the type if we know the operand is a pointer. */ - if (TREE_TYPE (expr) && POINTER_TYPE_P (TREE_TYPE (expr))) - return build_min (INDIRECT_REF, TREE_TYPE (TREE_TYPE (expr)), expr); - if (type_dependent_expression_p (expr)) - return build_min_nt_loc (loc, INDIRECT_REF, expr); - expr = build_non_dependent_expr (expr); - } - - rval = build_new_op (loc, INDIRECT_REF, LOOKUP_NORMAL, expr, - NULL_TREE, NULL_TREE, /*overload=*/NULL, complain); - if (!rval) - rval = cp_build_indirect_ref (expr, errorstring, complain); - - if (processing_template_decl && rval != error_mark_node) - return build_min_non_dep (INDIRECT_REF, rval, orig_expr); - else - return rval; -} - -/* Helper function called from c-common. */ -tree -build_indirect_ref (location_t /*loc*/, - tree ptr, ref_operator errorstring) -{ - return cp_build_indirect_ref (ptr, errorstring, tf_warning_or_error); -} - -tree -cp_build_indirect_ref (tree ptr, ref_operator errorstring, - tsubst_flags_t complain) -{ - tree pointer, type; - - if (ptr == current_class_ptr) - return current_class_ref; - - pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE - ? ptr : decay_conversion (ptr, complain)); - if (pointer == error_mark_node) - return error_mark_node; - - type = TREE_TYPE (pointer); - - if (POINTER_TYPE_P (type)) - { - /* [expr.unary.op] - - If the type of the expression is "pointer to T," the type - of the result is "T." */ - tree t = TREE_TYPE (type); - - if (CONVERT_EXPR_P (ptr) - || TREE_CODE (ptr) == VIEW_CONVERT_EXPR) - { - /* If a warning is issued, mark it to avoid duplicates from - the backend. This only needs to be done at - warn_strict_aliasing > 2. */ - if (warn_strict_aliasing > 2) - if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (ptr, 0)), - type, TREE_OPERAND (ptr, 0))) - TREE_NO_WARNING (ptr) = 1; - } - - if (VOID_TYPE_P (t)) - { - /* A pointer to incomplete type (other than cv void) can be - dereferenced [expr.unary.op]/1 */ - if (complain & tf_error) - error ("%qT is not a pointer-to-object type", type); - return error_mark_node; - } - else if (TREE_CODE (pointer) == ADDR_EXPR - && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0)))) - /* The POINTER was something like `&x'. We simplify `*&x' to - `x'. */ - return TREE_OPERAND (pointer, 0); - else - { - tree ref = build1 (INDIRECT_REF, t, pointer); - - /* We *must* set TREE_READONLY when dereferencing a pointer to const, - so that we get the proper error message if the result is used - to assign to. Also, &* is supposed to be a no-op. */ - TREE_READONLY (ref) = CP_TYPE_CONST_P (t); - TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t); - TREE_SIDE_EFFECTS (ref) - = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer)); - return ref; - } - } - else if (!(complain & tf_error)) - /* Don't emit any errors; we'll just return ERROR_MARK_NODE later. */ - ; - /* `pointer' won't be an error_mark_node if we were given a - pointer to member, so it's cool to check for this here. */ - else if (TYPE_PTRMEM_P (type)) - switch (errorstring) - { - case RO_ARRAY_INDEXING: - error ("invalid use of array indexing on pointer to member"); - break; - case RO_UNARY_STAR: - error ("invalid use of unary %<*%> on pointer to member"); - break; - case RO_IMPLICIT_CONVERSION: - error ("invalid use of implicit conversion on pointer to member"); - break; - case RO_ARROW_STAR: - error ("left hand operand of %<->*%> must be a pointer to class, " - "but is a pointer to member of type %qT", type); - break; - default: - gcc_unreachable (); - } - else if (pointer != error_mark_node) - invalid_indirection_error (input_location, type, errorstring); - - return error_mark_node; -} - -/* This handles expressions of the form "a[i]", which denotes - an array reference. - - This is logically equivalent in C to *(a+i), but we may do it differently. - If A is a variable or a member, we generate a primitive ARRAY_REF. - This avoids forcing the array out of registers, and can work on - arrays that are not lvalues (for example, members of structures returned - by functions). - - If INDEX is of some user-defined type, it must be converted to - integer type. Otherwise, to make a compatible PLUS_EXPR, it - will inherit the type of the array, which will be some pointer type. - - LOC is the location to use in building the array reference. */ - -tree -cp_build_array_ref (location_t loc, tree array, tree idx, - tsubst_flags_t complain) -{ - tree ret; - - if (idx == 0) - { - if (complain & tf_error) - error_at (loc, "subscript missing in array reference"); - return error_mark_node; - } - - if (TREE_TYPE (array) == error_mark_node - || TREE_TYPE (idx) == error_mark_node) - return error_mark_node; - - /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference - inside it. */ - switch (TREE_CODE (array)) - { - case COMPOUND_EXPR: - { - tree value = cp_build_array_ref (loc, TREE_OPERAND (array, 1), idx, - complain); - ret = build2 (COMPOUND_EXPR, TREE_TYPE (value), - TREE_OPERAND (array, 0), value); - SET_EXPR_LOCATION (ret, loc); - return ret; - } - - case COND_EXPR: - ret = build_conditional_expr - (TREE_OPERAND (array, 0), - cp_build_array_ref (loc, TREE_OPERAND (array, 1), idx, - complain), - cp_build_array_ref (loc, TREE_OPERAND (array, 2), idx, - complain), - complain); - protected_set_expr_location (ret, loc); - return ret; - - default: - break; - } - - convert_vector_to_pointer_for_subscript (loc, &array, idx); - - if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE) - { - tree rval, type; - - warn_array_subscript_with_type_char (idx); - - if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (idx))) - { - if (complain & tf_error) - error_at (loc, "array subscript is not an integer"); - return error_mark_node; - } - - /* Apply integral promotions *after* noticing character types. - (It is unclear why we do these promotions -- the standard - does not say that we should. In fact, the natural thing would - seem to be to convert IDX to ptrdiff_t; we're performing - pointer arithmetic.) */ - idx = cp_perform_integral_promotions (idx, complain); - - /* An array that is indexed by a non-constant - cannot be stored in a register; we must be able to do - address arithmetic on its address. - Likewise an array of elements of variable size. */ - if (TREE_CODE (idx) != INTEGER_CST - || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array))) - && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) - != INTEGER_CST))) - { - if (!cxx_mark_addressable (array)) - return error_mark_node; - } - - /* An array that is indexed by a constant value which is not within - the array bounds cannot be stored in a register either; because we - would get a crash in store_bit_field/extract_bit_field when trying - to access a non-existent part of the register. */ - if (TREE_CODE (idx) == INTEGER_CST - && TYPE_DOMAIN (TREE_TYPE (array)) - && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array)))) - { - if (!cxx_mark_addressable (array)) - return error_mark_node; - } - - if (!lvalue_p (array) && (complain & tf_error)) - pedwarn (loc, OPT_Wpedantic, - "ISO C++ forbids subscripting non-lvalue array"); - - /* Note in C++ it is valid to subscript a `register' array, since - it is valid to take the address of something with that - storage specification. */ - if (extra_warnings) - { - tree foo = array; - while (TREE_CODE (foo) == COMPONENT_REF) - foo = TREE_OPERAND (foo, 0); - if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo) - && (complain & tf_warning)) - warning_at (loc, OPT_Wextra, - "subscripting array declared %<register%>"); - } - - type = TREE_TYPE (TREE_TYPE (array)); - rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE); - /* Array ref is const/volatile if the array elements are - or if the array is.. */ - TREE_READONLY (rval) - |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array)); - TREE_SIDE_EFFECTS (rval) - |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array)); - TREE_THIS_VOLATILE (rval) - |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array)); - ret = require_complete_type_sfinae (fold_if_not_in_template (rval), - complain); - protected_set_expr_location (ret, loc); - return ret; - } - - { - tree ar = cp_default_conversion (array, complain); - tree ind = cp_default_conversion (idx, complain); - - /* Put the integer in IND to simplify error checking. */ - if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE) - { - tree temp = ar; - ar = ind; - ind = temp; - } - - if (ar == error_mark_node || ind == error_mark_node) - return error_mark_node; - - if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE) - { - if (complain & tf_error) - error_at (loc, "subscripted value is neither array nor pointer"); - return error_mark_node; - } - if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE) - { - if (complain & tf_error) - error_at (loc, "array subscript is not an integer"); - return error_mark_node; - } - - warn_array_subscript_with_type_char (idx); - - ret = cp_build_indirect_ref (cp_build_binary_op (input_location, - PLUS_EXPR, ar, ind, - complain), - RO_ARRAY_INDEXING, - complain); - protected_set_expr_location (ret, loc); - return ret; - } -} - -/* Entry point for Obj-C++. */ - -tree -build_array_ref (location_t loc, tree array, tree idx) -{ - return cp_build_array_ref (loc, array, idx, tf_warning_or_error); -} - -/* Resolve a pointer to member function. INSTANCE is the object - instance to use, if the member points to a virtual member. - - This used to avoid checking for virtual functions if basetype - has no virtual functions, according to an earlier ANSI draft. - With the final ISO C++ rules, such an optimization is - incorrect: A pointer to a derived member can be static_cast - to pointer-to-base-member, as long as the dynamic object - later has the right member. So now we only do this optimization - when we know the dynamic type of the object. */ - -tree -get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function, - tsubst_flags_t complain) -{ - if (TREE_CODE (function) == OFFSET_REF) - function = TREE_OPERAND (function, 1); - - if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function))) - { - tree idx, delta, e1, e2, e3, vtbl; - bool nonvirtual; - tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function)); - tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype)); - - tree instance_ptr = *instance_ptrptr; - tree instance_save_expr = 0; - if (instance_ptr == error_mark_node) - { - if (TREE_CODE (function) == PTRMEM_CST) - { - /* Extracting the function address from a pmf is only - allowed with -Wno-pmf-conversions. It only works for - pmf constants. */ - e1 = build_addr_func (PTRMEM_CST_MEMBER (function), complain); - e1 = convert (fntype, e1); - return e1; - } - else - { - if (complain & tf_error) - error ("object missing in use of %qE", function); - return error_mark_node; - } - } - - /* True if we know that the dynamic type of the object doesn't have - virtual functions, so we can assume the PFN field is a pointer. */ - nonvirtual = (COMPLETE_TYPE_P (basetype) - && !TYPE_POLYMORPHIC_P (basetype) - && resolves_to_fixed_type_p (instance_ptr, 0)); - - if (TREE_SIDE_EFFECTS (instance_ptr)) - instance_ptr = instance_save_expr = save_expr (instance_ptr); - - if (TREE_SIDE_EFFECTS (function)) - function = save_expr (function); - - /* Start by extracting all the information from the PMF itself. */ - e3 = pfn_from_ptrmemfunc (function); - delta = delta_from_ptrmemfunc (function); - idx = build1 (NOP_EXPR, vtable_index_type, e3); - switch (TARGET_PTRMEMFUNC_VBIT_LOCATION) - { - case ptrmemfunc_vbit_in_pfn: - e1 = cp_build_binary_op (input_location, - BIT_AND_EXPR, idx, integer_one_node, - complain); - idx = cp_build_binary_op (input_location, - MINUS_EXPR, idx, integer_one_node, - complain); - if (idx == error_mark_node) - return error_mark_node; - break; - - case ptrmemfunc_vbit_in_delta: - e1 = cp_build_binary_op (input_location, - BIT_AND_EXPR, delta, integer_one_node, - complain); - delta = cp_build_binary_op (input_location, - RSHIFT_EXPR, delta, integer_one_node, - complain); - if (delta == error_mark_node) - return error_mark_node; - break; - - default: - gcc_unreachable (); - } - - if (e1 == error_mark_node) - return error_mark_node; - - /* Convert down to the right base before using the instance. A - special case is that in a pointer to member of class C, C may - be incomplete. In that case, the function will of course be - a member of C, and no conversion is required. In fact, - lookup_base will fail in that case, because incomplete - classes do not have BINFOs. */ - if (!same_type_ignoring_top_level_qualifiers_p - (basetype, TREE_TYPE (TREE_TYPE (instance_ptr)))) - { - basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)), - basetype, ba_check, NULL, complain); - instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype, - 1, complain); - if (instance_ptr == error_mark_node) - return error_mark_node; - } - /* ...and then the delta in the PMF. */ - instance_ptr = fold_build_pointer_plus (instance_ptr, delta); - - /* Hand back the adjusted 'this' argument to our caller. */ - *instance_ptrptr = instance_ptr; - - if (nonvirtual) - /* Now just return the pointer. */ - return e3; - - /* Next extract the vtable pointer from the object. */ - vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node), - instance_ptr); - vtbl = cp_build_indirect_ref (vtbl, RO_NULL, complain); - if (vtbl == error_mark_node) - return error_mark_node; - - /* Finally, extract the function pointer from the vtable. */ - e2 = fold_build_pointer_plus_loc (input_location, vtbl, idx); - e2 = cp_build_indirect_ref (e2, RO_NULL, complain); - if (e2 == error_mark_node) - return error_mark_node; - TREE_CONSTANT (e2) = 1; - - /* When using function descriptors, the address of the - vtable entry is treated as a function pointer. */ - if (TARGET_VTABLE_USES_DESCRIPTORS) - e2 = build1 (NOP_EXPR, TREE_TYPE (e2), - cp_build_addr_expr (e2, complain)); - - e2 = fold_convert (TREE_TYPE (e3), e2); - e1 = build_conditional_expr (e1, e2, e3, complain); - if (e1 == error_mark_node) - return error_mark_node; - - /* Make sure this doesn't get evaluated first inside one of the - branches of the COND_EXPR. */ - if (instance_save_expr) - e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1), - instance_save_expr, e1); - - function = e1; - } - return function; -} - -/* Used by the C-common bits. */ -tree -build_function_call (location_t /*loc*/, - tree function, tree params) -{ - return cp_build_function_call (function, params, tf_warning_or_error); -} - -/* Used by the C-common bits. */ -tree -build_function_call_vec (location_t /*loc*/, - tree function, vec<tree, va_gc> *params, - vec<tree, va_gc> * /*origtypes*/) -{ - vec<tree, va_gc> *orig_params = params; - tree ret = cp_build_function_call_vec (function, ¶ms, - tf_warning_or_error); - - /* cp_build_function_call_vec can reallocate PARAMS by adding - default arguments. That should never happen here. Verify - that. */ - gcc_assert (params == orig_params); - - return ret; -} - -/* Build a function call using a tree list of arguments. */ - -tree -cp_build_function_call (tree function, tree params, tsubst_flags_t complain) -{ - vec<tree, va_gc> *vec; - tree ret; - - vec = make_tree_vector (); - for (; params != NULL_TREE; params = TREE_CHAIN (params)) - vec_safe_push (vec, TREE_VALUE (params)); - ret = cp_build_function_call_vec (function, &vec, complain); - release_tree_vector (vec); - return ret; -} - -/* Build a function call using varargs. */ - -tree -cp_build_function_call_nary (tree function, tsubst_flags_t complain, ...) -{ - vec<tree, va_gc> *vec; - va_list args; - tree ret, t; - - vec = make_tree_vector (); - va_start (args, complain); - for (t = va_arg (args, tree); t != NULL_TREE; t = va_arg (args, tree)) - vec_safe_push (vec, t); - va_end (args); - ret = cp_build_function_call_vec (function, &vec, complain); - release_tree_vector (vec); - return ret; -} - -/* Build a function call using a vector of arguments. PARAMS may be - NULL if there are no parameters. This changes the contents of - PARAMS. */ - -tree -cp_build_function_call_vec (tree function, vec<tree, va_gc> **params, - tsubst_flags_t complain) -{ - tree fntype, fndecl; - int is_method; - tree original = function; - int nargs; - tree *argarray; - tree parm_types; - vec<tree, va_gc> *allocated = NULL; - tree ret; - - /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF - expressions, like those used for ObjC messenger dispatches. */ - if (params != NULL && !vec_safe_is_empty (*params)) - function = objc_rewrite_function_call (function, (**params)[0]); - - /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue. - Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */ - if (TREE_CODE (function) == NOP_EXPR - && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0))) - function = TREE_OPERAND (function, 0); - - if (TREE_CODE (function) == FUNCTION_DECL) - { - mark_used (function); - fndecl = function; - - /* Convert anything with function type to a pointer-to-function. */ - if (DECL_MAIN_P (function) && (complain & tf_error)) - pedwarn (input_location, OPT_Wpedantic, - "ISO C++ forbids calling %<::main%> from within program"); - - function = build_addr_func (function, complain); - } - else - { - fndecl = NULL_TREE; - - function = build_addr_func (function, complain); - } - - if (function == error_mark_node) - return error_mark_node; - - fntype = TREE_TYPE (function); - - if (TYPE_PTRMEMFUNC_P (fntype)) - { - if (complain & tf_error) - error ("must use %<.*%> or %<->*%> to call pointer-to-member " - "function in %<%E (...)%>, e.g. %<(... ->* %E) (...)%>", - original, original); - return error_mark_node; - } - - is_method = (TREE_CODE (fntype) == POINTER_TYPE - && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE); - - if (!((TREE_CODE (fntype) == POINTER_TYPE - && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE) - || is_method - || TREE_CODE (function) == TEMPLATE_ID_EXPR)) - { - if (complain & tf_error) - { - if (!flag_diagnostics_show_caret) - error_at (input_location, - "%qE cannot be used as a function", original); - else if (DECL_P (original)) - error_at (input_location, - "%qD cannot be used as a function", original); - else - error_at (input_location, - "expression cannot be used as a function"); - } - - return error_mark_node; - } - - /* fntype now gets the type of function pointed to. */ - fntype = TREE_TYPE (fntype); - parm_types = TYPE_ARG_TYPES (fntype); - - if (params == NULL) - { - allocated = make_tree_vector (); - params = &allocated; - } - - nargs = convert_arguments (parm_types, params, fndecl, LOOKUP_NORMAL, - complain); - if (nargs < 0) - return error_mark_node; - - argarray = (*params)->address (); - - /* Check for errors in format strings and inappropriately - null parameters. */ - check_function_arguments (fntype, nargs, argarray); - - ret = build_cxx_call (function, nargs, argarray, complain); - - if (allocated != NULL) - release_tree_vector (allocated); - - return ret; -} - -/* Subroutine of convert_arguments. - Warn about wrong number of args are genereted. */ - -static void -warn_args_num (location_t loc, tree fndecl, bool too_many_p) -{ - if (fndecl) - { - if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE) - { - if (DECL_NAME (fndecl) == NULL_TREE - || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl))) - error_at (loc, - too_many_p - ? G_("too many arguments to constructor %q#D") - : G_("too few arguments to constructor %q#D"), - fndecl); - else - error_at (loc, - too_many_p - ? G_("too many arguments to member function %q#D") - : G_("too few arguments to member function %q#D"), - fndecl); - } - else - error_at (loc, - too_many_p - ? G_("too many arguments to function %q#D") - : G_("too few arguments to function %q#D"), - fndecl); - inform (DECL_SOURCE_LOCATION (fndecl), - "declared here"); - } - else - { - if (c_dialect_objc () && objc_message_selector ()) - error_at (loc, - too_many_p - ? G_("too many arguments to method %q#D") - : G_("too few arguments to method %q#D"), - objc_message_selector ()); - else - error_at (loc, too_many_p ? G_("too many arguments to function") - : G_("too few arguments to function")); - } -} - -/* Convert the actual parameter expressions in the list VALUES to the - types in the list TYPELIST. The converted expressions are stored - back in the VALUES vector. - If parmdecls is exhausted, or when an element has NULL as its type, - perform the default conversions. - - NAME is an IDENTIFIER_NODE or 0. It is used only for error messages. - - This is also where warnings about wrong number of args are generated. - - Returns the actual number of arguments processed (which might be less - than the length of the vector), or -1 on error. - - In C++, unspecified trailing parameters can be filled in with their - default arguments, if such were specified. Do so here. */ - -static int -convert_arguments (tree typelist, vec<tree, va_gc> **values, tree fndecl, - int flags, tsubst_flags_t complain) -{ - tree typetail; - unsigned int i; - - /* Argument passing is always copy-initialization. */ - flags |= LOOKUP_ONLYCONVERTING; - - for (i = 0, typetail = typelist; - i < vec_safe_length (*values); - i++) - { - tree type = typetail ? TREE_VALUE (typetail) : 0; - tree val = (**values)[i]; - - if (val == error_mark_node || type == error_mark_node) - return -1; - - if (type == void_type_node) - { - if (complain & tf_error) - { - warn_args_num (input_location, fndecl, /*too_many_p=*/true); - return i; - } - else - return -1; - } - - /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue. - Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */ - if (TREE_CODE (val) == NOP_EXPR - && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)) - && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)) - val = TREE_OPERAND (val, 0); - - if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE) - { - if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE - || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE - || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE) - val = decay_conversion (val, complain); - } - - if (val == error_mark_node) - return -1; - - if (type != 0) - { - /* Formal parm type is specified by a function prototype. */ - tree parmval; - - if (!COMPLETE_TYPE_P (complete_type (type))) - { - if (complain & tf_error) - { - if (fndecl) - error ("parameter %P of %qD has incomplete type %qT", - i, fndecl, type); - else - error ("parameter %P has incomplete type %qT", i, type); - } - parmval = error_mark_node; - } - else - { - parmval = convert_for_initialization - (NULL_TREE, type, val, flags, - ICR_ARGPASS, fndecl, i, complain); - parmval = convert_for_arg_passing (type, parmval, complain); - } - - if (parmval == error_mark_node) - return -1; - - (**values)[i] = parmval; - } - else - { - if (fndecl && DECL_BUILT_IN (fndecl) - && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P) - /* Don't do ellipsis conversion for __built_in_constant_p - as this will result in spurious errors for non-trivial - types. */ - val = require_complete_type_sfinae (val, complain); - else - val = convert_arg_to_ellipsis (val, complain); - - (**values)[i] = val; - } - - if (typetail) - typetail = TREE_CHAIN (typetail); - } - - if (typetail != 0 && typetail != void_list_node) - { - /* See if there are default arguments that can be used. Because - we hold default arguments in the FUNCTION_TYPE (which is so - wrong), we can see default parameters here from deduced - contexts (and via typeof) for indirect function calls. - Fortunately we know whether we have a function decl to - provide default arguments in a language conformant - manner. */ - if (fndecl && TREE_PURPOSE (typetail) - && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG) - { - for (; typetail != void_list_node; ++i) - { - tree parmval - = convert_default_arg (TREE_VALUE (typetail), - TREE_PURPOSE (typetail), - fndecl, i, complain); - - if (parmval == error_mark_node) - return -1; - - vec_safe_push (*values, parmval); - typetail = TREE_CHAIN (typetail); - /* ends with `...'. */ - if (typetail == NULL_TREE) - break; - } - } - else - { - if (complain & tf_error) - warn_args_num (input_location, fndecl, /*too_many_p=*/false); - return -1; - } - } - - return (int) i; -} - -/* Build a binary-operation expression, after performing default - conversions on the operands. CODE is the kind of expression to - build. ARG1 and ARG2 are the arguments. ARG1_CODE and ARG2_CODE - are the tree codes which correspond to ARG1 and ARG2 when issuing - warnings about possibly misplaced parentheses. They may differ - from the TREE_CODE of ARG1 and ARG2 if the parser has done constant - folding (e.g., if the parser sees "a | 1 + 1", it may call this - routine with ARG2 being an INTEGER_CST and ARG2_CODE == PLUS_EXPR). - To avoid issuing any parentheses warnings, pass ARG1_CODE and/or - ARG2_CODE as ERROR_MARK. */ - -tree -build_x_binary_op (location_t loc, enum tree_code code, tree arg1, - enum tree_code arg1_code, tree arg2, - enum tree_code arg2_code, tree *overload, - tsubst_flags_t complain) -{ - tree orig_arg1; - tree orig_arg2; - tree expr; - - orig_arg1 = arg1; - orig_arg2 = arg2; - - if (processing_template_decl) - { - if (type_dependent_expression_p (arg1) - || type_dependent_expression_p (arg2)) - return build_min_nt_loc (loc, code, arg1, arg2); - arg1 = build_non_dependent_expr (arg1); - arg2 = build_non_dependent_expr (arg2); - } - - if (code == DOTSTAR_EXPR) - expr = build_m_component_ref (arg1, arg2, complain); - else - expr = build_new_op (loc, code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE, - overload, complain); - - /* Check for cases such as x+y<<z which users are likely to - misinterpret. But don't warn about obj << x + y, since that is a - common idiom for I/O. */ - if (warn_parentheses - && (complain & tf_warning) - && !processing_template_decl - && !error_operand_p (arg1) - && !error_operand_p (arg2) - && (code != LSHIFT_EXPR - || !CLASS_TYPE_P (TREE_TYPE (arg1)))) - warn_about_parentheses (loc, code, arg1_code, orig_arg1, - arg2_code, orig_arg2); - - if (processing_template_decl && expr != error_mark_node) - return build_min_non_dep (code, expr, orig_arg1, orig_arg2); - - return expr; -} - -/* Build and return an ARRAY_REF expression. */ - -tree -build_x_array_ref (location_t loc, tree arg1, tree arg2, - tsubst_flags_t complain) -{ - tree orig_arg1 = arg1; - tree orig_arg2 = arg2; - tree expr; - - if (processing_template_decl) - { - if (type_dependent_expression_p (arg1) - || type_dependent_expression_p (arg2)) - return build_min_nt_loc (loc, ARRAY_REF, arg1, arg2, - NULL_TREE, NULL_TREE); - arg1 = build_non_dependent_expr (arg1); - arg2 = build_non_dependent_expr (arg2); - } - - expr = build_new_op (loc, ARRAY_REF, LOOKUP_NORMAL, arg1, arg2, - NULL_TREE, /*overload=*/NULL, complain); - - if (processing_template_decl && expr != error_mark_node) - return build_min_non_dep (ARRAY_REF, expr, orig_arg1, orig_arg2, - NULL_TREE, NULL_TREE); - return expr; -} - -/* Return whether OP is an expression of enum type cast to integer - type. In C++ even unsigned enum types are cast to signed integer - types. We do not want to issue warnings about comparisons between - signed and unsigned types when one of the types is an enum type. - Those warnings are always false positives in practice. */ - -static bool -enum_cast_to_int (tree op) -{ - if (TREE_CODE (op) == NOP_EXPR - && TREE_TYPE (op) == integer_type_node - && TREE_CODE (TREE_TYPE (TREE_OPERAND (op, 0))) == ENUMERAL_TYPE - && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op, 0)))) - return true; - - /* The cast may have been pushed into a COND_EXPR. */ - if (TREE_CODE (op) == COND_EXPR) - return (enum_cast_to_int (TREE_OPERAND (op, 1)) - || enum_cast_to_int (TREE_OPERAND (op, 2))); - - return false; -} - -/* For the c-common bits. */ -tree -build_binary_op (location_t location, enum tree_code code, tree op0, tree op1, - int /*convert_p*/) -{ - return cp_build_binary_op (location, code, op0, op1, tf_warning_or_error); -} - - -/* Build a binary-operation expression without default conversions. - CODE is the kind of expression to build. - LOCATION is the location_t of the operator in the source code. - This function differs from `build' in several ways: - the data type of the result is computed and recorded in it, - warnings are generated if arg data types are invalid, - special handling for addition and subtraction of pointers is known, - and some optimization is done (operations on narrow ints - are done in the narrower type when that gives the same result). - Constant folding is also done before the result is returned. - - Note that the operands will never have enumeral types - because either they have just had the default conversions performed - or they have both just been converted to some other type in which - the arithmetic is to be done. - - C++: must do special pointer arithmetic when implementing - multiple inheritance, and deal with pointer to member functions. */ - -tree -cp_build_binary_op (location_t location, - enum tree_code code, tree orig_op0, tree orig_op1, - tsubst_flags_t complain) -{ - tree op0, op1; - enum tree_code code0, code1; - tree type0, type1; - const char *invalid_op_diag; - - /* Expression code to give to the expression when it is built. - Normally this is CODE, which is what the caller asked for, - but in some special cases we change it. */ - enum tree_code resultcode = code; - - /* Data type in which the computation is to be performed. - In the simplest cases this is the common type of the arguments. */ - tree result_type = NULL; - - /* Nonzero means operands have already been type-converted - in whatever way is necessary. - Zero means they need to be converted to RESULT_TYPE. */ - int converted = 0; - - /* Nonzero means create the expression with this type, rather than - RESULT_TYPE. */ - tree build_type = 0; - - /* Nonzero means after finally constructing the expression - convert it to this type. */ - tree final_type = 0; - - tree result; - - /* Nonzero if this is an operation like MIN or MAX which can - safely be computed in short if both args are promoted shorts. - Also implies COMMON. - -1 indicates a bitwise operation; this makes a difference - in the exact conditions for when it is safe to do the operation - in a narrower mode. */ - int shorten = 0; - - /* Nonzero if this is a comparison operation; - if both args are promoted shorts, compare the original shorts. - Also implies COMMON. */ - int short_compare = 0; - - /* Nonzero means set RESULT_TYPE to the common type of the args. */ - int common = 0; - - /* True if both operands have arithmetic type. */ - bool arithmetic_types_p; - - /* Apply default conversions. */ - op0 = orig_op0; - op1 = orig_op1; - - if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR - || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR - || code == TRUTH_XOR_EXPR) - { - if (!really_overloaded_fn (op0) && !VOID_TYPE_P (TREE_TYPE (op0))) - op0 = decay_conversion (op0, complain); - if (!really_overloaded_fn (op1) && !VOID_TYPE_P (TREE_TYPE (op1))) - op1 = decay_conversion (op1, complain); - } - else - { - if (!really_overloaded_fn (op0) && !VOID_TYPE_P (TREE_TYPE (op0))) - op0 = cp_default_conversion (op0, complain); - if (!really_overloaded_fn (op1) && !VOID_TYPE_P (TREE_TYPE (op1))) - op1 = cp_default_conversion (op1, complain); - } - - /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */ - STRIP_TYPE_NOPS (op0); - STRIP_TYPE_NOPS (op1); - - /* DTRT if one side is an overloaded function, but complain about it. */ - if (type_unknown_p (op0)) - { - tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none); - if (t != error_mark_node) - { - if (complain & tf_error) - permerror (input_location, "assuming cast to type %qT from overloaded function", - TREE_TYPE (t)); - op0 = t; - } - } - if (type_unknown_p (op1)) - { - tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none); - if (t != error_mark_node) - { - if (complain & tf_error) - permerror (input_location, "assuming cast to type %qT from overloaded function", - TREE_TYPE (t)); - op1 = t; - } - } - - type0 = TREE_TYPE (op0); - type1 = TREE_TYPE (op1); - - /* The expression codes of the data types of the arguments tell us - whether the arguments are integers, floating, pointers, etc. */ - code0 = TREE_CODE (type0); - code1 = TREE_CODE (type1); - - /* If an error was already reported for one of the arguments, - avoid reporting another error. */ - if (code0 == ERROR_MARK || code1 == ERROR_MARK) - return error_mark_node; - - if ((invalid_op_diag - = targetm.invalid_binary_op (code, type0, type1))) - { - error (invalid_op_diag); - return error_mark_node; - } - - /* Issue warnings about peculiar, but valid, uses of NULL. */ - if ((orig_op0 == null_node || orig_op1 == null_node) - /* It's reasonable to use pointer values as operands of && - and ||, so NULL is no exception. */ - && code != TRUTH_ANDIF_EXPR && code != TRUTH_ORIF_EXPR - && ( /* Both are NULL (or 0) and the operation was not a - comparison or a pointer subtraction. */ - (null_ptr_cst_p (orig_op0) && null_ptr_cst_p (orig_op1) - && code != EQ_EXPR && code != NE_EXPR && code != MINUS_EXPR) - /* Or if one of OP0 or OP1 is neither a pointer nor NULL. */ - || (!null_ptr_cst_p (orig_op0) - && !TYPE_PTR_OR_PTRMEM_P (type0)) - || (!null_ptr_cst_p (orig_op1) - && !TYPE_PTR_OR_PTRMEM_P (type1))) - && (complain & tf_warning)) - { - source_location loc = - expansion_point_location_if_in_system_header (input_location); - - warning_at (loc, OPT_Wpointer_arith, "NULL used in arithmetic"); - } - - /* In case when one of the operands of the binary operation is - a vector and another is a scalar -- convert scalar to vector. */ - if ((code0 == VECTOR_TYPE) != (code1 == VECTOR_TYPE)) - { - enum stv_conv convert_flag = scalar_to_vector (location, code, op0, op1, - complain & tf_error); - - switch (convert_flag) - { - case stv_error: - return error_mark_node; - case stv_firstarg: - { - op0 = save_expr (op0); - op0 = convert (TREE_TYPE (type1), op0); - op0 = build_vector_from_val (type1, op0); - type0 = TREE_TYPE (op0); - code0 = TREE_CODE (type0); - converted = 1; - break; - } - case stv_secondarg: - { - op1 = save_expr (op1); - op1 = convert (TREE_TYPE (type0), op1); - op1 = build_vector_from_val (type0, op1); - type1 = TREE_TYPE (op1); - code1 = TREE_CODE (type1); - converted = 1; - break; - } - default: - break; - } - } - - switch (code) - { - case MINUS_EXPR: - /* Subtraction of two similar pointers. - We must subtract them as integers, then divide by object size. */ - if (code0 == POINTER_TYPE && code1 == POINTER_TYPE - && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0), - TREE_TYPE (type1))) - return pointer_diff (op0, op1, common_pointer_type (type0, type1), - complain); - /* In all other cases except pointer - int, the usual arithmetic - rules apply. */ - else if (!(code0 == POINTER_TYPE && code1 == INTEGER_TYPE)) - { - common = 1; - break; - } - /* The pointer - int case is just like pointer + int; fall - through. */ - case PLUS_EXPR: - if ((code0 == POINTER_TYPE || code1 == POINTER_TYPE) - && (code0 == INTEGER_TYPE || code1 == INTEGER_TYPE)) - { - tree ptr_operand; - tree int_operand; - ptr_operand = ((code0 == POINTER_TYPE) ? op0 : op1); - int_operand = ((code0 == INTEGER_TYPE) ? op0 : op1); - if (processing_template_decl) - { - result_type = TREE_TYPE (ptr_operand); - break; - } - return cp_pointer_int_sum (code, - ptr_operand, - int_operand); - } - common = 1; - break; - - case MULT_EXPR: - common = 1; - break; - - case TRUNC_DIV_EXPR: - case CEIL_DIV_EXPR: - case FLOOR_DIV_EXPR: - case ROUND_DIV_EXPR: - case EXACT_DIV_EXPR: - if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE - || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE) - && (code1 == INTEGER_TYPE || code1 == REAL_TYPE - || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)) - { - enum tree_code tcode0 = code0, tcode1 = code1; - tree cop1 = fold_non_dependent_expr_sfinae (op1, tf_none); - - warn_for_div_by_zero (location, maybe_constant_value (cop1)); - - if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE) - tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0))); - if (tcode1 == COMPLEX_TYPE || tcode1 == VECTOR_TYPE) - tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1))); - - if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE)) - resultcode = RDIV_EXPR; - else - /* When dividing two signed integers, we have to promote to int. - unless we divide by a constant != -1. Note that default - conversion will have been performed on the operands at this - point, so we have to dig out the original type to find out if - it was unsigned. */ - shorten = ((TREE_CODE (op0) == NOP_EXPR - && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0)))) - || (TREE_CODE (op1) == INTEGER_CST - && ! integer_all_onesp (op1))); - - common = 1; - } - break; - - case BIT_AND_EXPR: - case BIT_IOR_EXPR: - case BIT_XOR_EXPR: - if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) - || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE - && !VECTOR_FLOAT_TYPE_P (type0) - && !VECTOR_FLOAT_TYPE_P (type1))) - shorten = -1; - break; - - case TRUNC_MOD_EXPR: - case FLOOR_MOD_EXPR: - { - tree cop1 = fold_non_dependent_expr_sfinae (op1, tf_none); - - warn_for_div_by_zero (location, maybe_constant_value (cop1)); - } - - if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE - && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE - && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE) - common = 1; - else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) - { - /* Although it would be tempting to shorten always here, that loses - on some targets, since the modulo instruction is undefined if the - quotient can't be represented in the computation mode. We shorten - only if unsigned or if dividing by something we know != -1. */ - shorten = ((TREE_CODE (op0) == NOP_EXPR - && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0)))) - || (TREE_CODE (op1) == INTEGER_CST - && ! integer_all_onesp (op1))); - common = 1; - } - break; - - case TRUTH_ANDIF_EXPR: - case TRUTH_ORIF_EXPR: - case TRUTH_AND_EXPR: - case TRUTH_OR_EXPR: - result_type = boolean_type_node; - break; - - /* Shift operations: result has same type as first operand; - always convert second operand to int. - Also set SHORT_SHIFT if shifting rightward. */ - - case RSHIFT_EXPR: - if (code0 == VECTOR_TYPE && code1 == INTEGER_TYPE - && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE) - { - result_type = type0; - converted = 1; - } - else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE - && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE - && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE - && TYPE_VECTOR_SUBPARTS (type0) == TYPE_VECTOR_SUBPARTS (type1)) - { - result_type = type0; - converted = 1; - } - else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) - { - tree const_op1 = fold_non_dependent_expr_sfinae (op1, tf_none); - const_op1 = maybe_constant_value (const_op1); - if (TREE_CODE (const_op1) != INTEGER_CST) - const_op1 = op1; - result_type = type0; - if (TREE_CODE (const_op1) == INTEGER_CST) - { - if (tree_int_cst_lt (const_op1, integer_zero_node)) - { - if ((complain & tf_warning) - && c_inhibit_evaluation_warnings == 0) - warning (0, "right shift count is negative"); - } - else - { - if (compare_tree_int (const_op1, TYPE_PRECISION (type0)) >= 0 - && (complain & tf_warning) - && c_inhibit_evaluation_warnings == 0) - warning (0, "right shift count >= width of type"); - } - } - /* Convert the shift-count to an integer, regardless of - size of value being shifted. */ - if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) - op1 = cp_convert (integer_type_node, op1, complain); - /* Avoid converting op1 to result_type later. */ - converted = 1; - } - break; - - case LSHIFT_EXPR: - if (code0 == VECTOR_TYPE && code1 == INTEGER_TYPE - && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE) - { - result_type = type0; - converted = 1; - } - else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE - && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE - && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE - && TYPE_VECTOR_SUBPARTS (type0) == TYPE_VECTOR_SUBPARTS (type1)) - { - result_type = type0; - converted = 1; - } - else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) - { - tree const_op1 = fold_non_dependent_expr_sfinae (op1, tf_none); - const_op1 = maybe_constant_value (const_op1); - if (TREE_CODE (const_op1) != INTEGER_CST) - const_op1 = op1; - result_type = type0; - if (TREE_CODE (const_op1) == INTEGER_CST) - { - if (tree_int_cst_lt (const_op1, integer_zero_node)) - { - if ((complain & tf_warning) - && c_inhibit_evaluation_warnings == 0) - warning (0, "left shift count is negative"); - } - else if (compare_tree_int (const_op1, - TYPE_PRECISION (type0)) >= 0) - { - if ((complain & tf_warning) - && c_inhibit_evaluation_warnings == 0) - warning (0, "left shift count >= width of type"); - } - } - /* Convert the shift-count to an integer, regardless of - size of value being shifted. */ - if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) - op1 = cp_convert (integer_type_node, op1, complain); - /* Avoid converting op1 to result_type later. */ - converted = 1; - } - break; - - case RROTATE_EXPR: - case LROTATE_EXPR: - if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) - { - result_type = type0; - if (TREE_CODE (op1) == INTEGER_CST) - { - if (tree_int_cst_lt (op1, integer_zero_node)) - { - if (complain & tf_warning) - warning (0, (code == LROTATE_EXPR) - ? G_("left rotate count is negative") - : G_("right rotate count is negative")); - } - else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0) - { - if (complain & tf_warning) - warning (0, (code == LROTATE_EXPR) - ? G_("left rotate count >= width of type") - : G_("right rotate count >= width of type")); - } - } - /* Convert the shift-count to an integer, regardless of - size of value being shifted. */ - if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) - op1 = cp_convert (integer_type_node, op1, complain); - } - break; - - case EQ_EXPR: - case NE_EXPR: - if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE) - goto vector_compare; - if ((complain & tf_warning) - && (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1))) - warning (OPT_Wfloat_equal, - "comparing floating point with == or != is unsafe"); - if ((complain & tf_warning) - && ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1)) - || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0)))) - warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour"); - - build_type = boolean_type_node; - if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE - || code0 == COMPLEX_TYPE || code0 == ENUMERAL_TYPE) - && (code1 == INTEGER_TYPE || code1 == REAL_TYPE - || code1 == COMPLEX_TYPE || code1 == ENUMERAL_TYPE)) - short_compare = 1; - else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE) - || (TYPE_PTRDATAMEM_P (type0) && TYPE_PTRDATAMEM_P (type1))) - result_type = composite_pointer_type (type0, type1, op0, op1, - CPO_COMPARISON, complain); - else if ((code0 == POINTER_TYPE || TYPE_PTRDATAMEM_P (type0)) - && null_ptr_cst_p (op1)) - { - if (TREE_CODE (op0) == ADDR_EXPR - && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0))) - { - if ((complain & tf_warning) - && c_inhibit_evaluation_warnings == 0) - warning (OPT_Waddress, "the address of %qD will never be NULL", - TREE_OPERAND (op0, 0)); - } - result_type = type0; - } - else if ((code1 == POINTER_TYPE || TYPE_PTRDATAMEM_P (type1)) - && null_ptr_cst_p (op0)) - { - if (TREE_CODE (op1) == ADDR_EXPR - && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0))) - { - if ((complain & tf_warning) - && c_inhibit_evaluation_warnings == 0) - warning (OPT_Waddress, "the address of %qD will never be NULL", - TREE_OPERAND (op1, 0)); - } - result_type = type1; - } - else if (null_ptr_cst_p (op0) && null_ptr_cst_p (op1)) - /* One of the operands must be of nullptr_t type. */ - result_type = TREE_TYPE (nullptr_node); - else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) - { - result_type = type0; - if (complain & tf_error) - permerror (input_location, "ISO C++ forbids comparison between pointer and integer"); - else - return error_mark_node; - } - else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) - { - result_type = type1; - if (complain & tf_error) - permerror (input_location, "ISO C++ forbids comparison between pointer and integer"); - else - return error_mark_node; - } - else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1)) - { - if (TARGET_PTRMEMFUNC_VBIT_LOCATION - == ptrmemfunc_vbit_in_delta) - { - tree pfn0, delta0, e1, e2; - - if (TREE_SIDE_EFFECTS (op0)) - op0 = save_expr (op0); - - pfn0 = pfn_from_ptrmemfunc (op0); - delta0 = delta_from_ptrmemfunc (op0); - e1 = cp_build_binary_op (location, - EQ_EXPR, - pfn0, - build_zero_cst (TREE_TYPE (pfn0)), - complain); - e2 = cp_build_binary_op (location, - BIT_AND_EXPR, - delta0, - integer_one_node, - complain); - - if (complain & tf_warning) - maybe_warn_zero_as_null_pointer_constant (op1, input_location); - - e2 = cp_build_binary_op (location, - EQ_EXPR, e2, integer_zero_node, - complain); - op0 = cp_build_binary_op (location, - TRUTH_ANDIF_EXPR, e1, e2, - complain); - op1 = cp_convert (TREE_TYPE (op0), integer_one_node, complain); - } - else - { - op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier); - op1 = cp_convert (TREE_TYPE (op0), op1, complain); - } - result_type = TREE_TYPE (op0); - } - else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0)) - return cp_build_binary_op (location, code, op1, op0, complain); - else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)) - { - tree type; - /* E will be the final comparison. */ - tree e; - /* E1 and E2 are for scratch. */ - tree e1; - tree e2; - tree pfn0; - tree pfn1; - tree delta0; - tree delta1; - - type = composite_pointer_type (type0, type1, op0, op1, - CPO_COMPARISON, complain); - - if (!same_type_p (TREE_TYPE (op0), type)) - op0 = cp_convert_and_check (type, op0, complain); - if (!same_type_p (TREE_TYPE (op1), type)) - op1 = cp_convert_and_check (type, op1, complain); - - if (op0 == error_mark_node || op1 == error_mark_node) - return error_mark_node; - - if (TREE_SIDE_EFFECTS (op0)) - op0 = save_expr (op0); - if (TREE_SIDE_EFFECTS (op1)) - op1 = save_expr (op1); - - pfn0 = pfn_from_ptrmemfunc (op0); - pfn1 = pfn_from_ptrmemfunc (op1); - delta0 = delta_from_ptrmemfunc (op0); - delta1 = delta_from_ptrmemfunc (op1); - if (TARGET_PTRMEMFUNC_VBIT_LOCATION - == ptrmemfunc_vbit_in_delta) - { - /* We generate: - - (op0.pfn == op1.pfn - && ((op0.delta == op1.delta) - || (!op0.pfn && op0.delta & 1 == 0 - && op1.delta & 1 == 0)) - - The reason for the `!op0.pfn' bit is that a NULL - pointer-to-member is any member with a zero PFN and - LSB of the DELTA field is 0. */ - - e1 = cp_build_binary_op (location, BIT_AND_EXPR, - delta0, - integer_one_node, - complain); - e1 = cp_build_binary_op (location, - EQ_EXPR, e1, integer_zero_node, - complain); - e2 = cp_build_binary_op (location, BIT_AND_EXPR, - delta1, - integer_one_node, - complain); - e2 = cp_build_binary_op (location, - EQ_EXPR, e2, integer_zero_node, - complain); - e1 = cp_build_binary_op (location, - TRUTH_ANDIF_EXPR, e2, e1, - complain); - e2 = cp_build_binary_op (location, EQ_EXPR, - pfn0, - build_zero_cst (TREE_TYPE (pfn0)), - complain); - e2 = cp_build_binary_op (location, - TRUTH_ANDIF_EXPR, e2, e1, complain); - e1 = cp_build_binary_op (location, - EQ_EXPR, delta0, delta1, complain); - e1 = cp_build_binary_op (location, - TRUTH_ORIF_EXPR, e1, e2, complain); - } - else - { - /* We generate: - - (op0.pfn == op1.pfn - && (!op0.pfn || op0.delta == op1.delta)) - - The reason for the `!op0.pfn' bit is that a NULL - pointer-to-member is any member with a zero PFN; the - DELTA field is unspecified. */ - - e1 = cp_build_binary_op (location, - EQ_EXPR, delta0, delta1, complain); - e2 = cp_build_binary_op (location, - EQ_EXPR, - pfn0, - build_zero_cst (TREE_TYPE (pfn0)), - complain); - e1 = cp_build_binary_op (location, - TRUTH_ORIF_EXPR, e1, e2, complain); - } - e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1); - e = cp_build_binary_op (location, - TRUTH_ANDIF_EXPR, e2, e1, complain); - if (code == EQ_EXPR) - return e; - return cp_build_binary_op (location, - EQ_EXPR, e, integer_zero_node, complain); - } - else - { - gcc_assert (!TYPE_PTRMEMFUNC_P (type0) - || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0), - type1)); - gcc_assert (!TYPE_PTRMEMFUNC_P (type1) - || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1), - type0)); - } - - break; - - case MAX_EXPR: - case MIN_EXPR: - if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) - && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) - shorten = 1; - else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) - result_type = composite_pointer_type (type0, type1, op0, op1, - CPO_COMPARISON, complain); - break; - - case LE_EXPR: - case GE_EXPR: - case LT_EXPR: - case GT_EXPR: - if (TREE_CODE (orig_op0) == STRING_CST - || TREE_CODE (orig_op1) == STRING_CST) - { - if (complain & tf_warning) - warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour"); - } - - if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE) - { - vector_compare: - tree intt; - if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0), - TREE_TYPE (type1))) - { - error_at (location, "comparing vectors with different " - "element types"); - inform (location, "operand types are %qT and %qT", type0, type1); - return error_mark_node; - } - - if (TYPE_VECTOR_SUBPARTS (type0) != TYPE_VECTOR_SUBPARTS (type1)) - { - error_at (location, "comparing vectors with different " - "number of elements"); - inform (location, "operand types are %qT and %qT", type0, type1); - return error_mark_node; - } - - /* Always construct signed integer vector type. */ - intt = c_common_type_for_size (GET_MODE_BITSIZE - (TYPE_MODE (TREE_TYPE (type0))), 0); - result_type = build_opaque_vector_type (intt, - TYPE_VECTOR_SUBPARTS (type0)); - converted = 1; - break; - } - build_type = boolean_type_node; - if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE - || code0 == ENUMERAL_TYPE) - && (code1 == INTEGER_TYPE || code1 == REAL_TYPE - || code1 == ENUMERAL_TYPE)) - short_compare = 1; - else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) - result_type = composite_pointer_type (type0, type1, op0, op1, - CPO_COMPARISON, complain); - else if (code0 == POINTER_TYPE && null_ptr_cst_p (op1)) - { - result_type = type0; - if (extra_warnings && (complain & tf_warning)) - warning (OPT_Wextra, - "ordered comparison of pointer with integer zero"); - } - else if (code1 == POINTER_TYPE && null_ptr_cst_p (op0)) - { - result_type = type1; - if (extra_warnings && (complain & tf_warning)) - warning (OPT_Wextra, - "ordered comparison of pointer with integer zero"); - } - else if (null_ptr_cst_p (op0) && null_ptr_cst_p (op1)) - /* One of the operands must be of nullptr_t type. */ - result_type = TREE_TYPE (nullptr_node); - else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) - { - result_type = type0; - if (complain & tf_error) - permerror (input_location, "ISO C++ forbids comparison between pointer and integer"); - else - return error_mark_node; - } - else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) - { - result_type = type1; - if (complain & tf_error) - permerror (input_location, "ISO C++ forbids comparison between pointer and integer"); - else - return error_mark_node; - } - break; - - case UNORDERED_EXPR: - case ORDERED_EXPR: - case UNLT_EXPR: - case UNLE_EXPR: - case UNGT_EXPR: - case UNGE_EXPR: - case UNEQ_EXPR: - build_type = integer_type_node; - if (code0 != REAL_TYPE || code1 != REAL_TYPE) - { - if (complain & tf_error) - error ("unordered comparison on non-floating point argument"); - return error_mark_node; - } - common = 1; - break; - - default: - break; - } - - if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE - || code0 == ENUMERAL_TYPE) - && (code1 == INTEGER_TYPE || code1 == REAL_TYPE - || code1 == COMPLEX_TYPE || code1 == ENUMERAL_TYPE))) - arithmetic_types_p = 1; - else - { - arithmetic_types_p = 0; - /* Vector arithmetic is only allowed when both sides are vectors. */ - if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE) - { - if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1)) - || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0), - TREE_TYPE (type1))) - { - binary_op_error (location, code, type0, type1); - return error_mark_node; - } - arithmetic_types_p = 1; - } - } - /* Determine the RESULT_TYPE, if it is not already known. */ - if (!result_type - && arithmetic_types_p - && (shorten || common || short_compare)) - { - result_type = cp_common_type (type0, type1); - do_warn_double_promotion (result_type, type0, type1, - "implicit conversion from %qT to %qT " - "to match other operand of binary " - "expression", - location); - } - - if (!result_type) - { - if (complain & tf_error) - error ("invalid operands of types %qT and %qT to binary %qO", - TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code); - return error_mark_node; - } - - /* If we're in a template, the only thing we need to know is the - RESULT_TYPE. */ - if (processing_template_decl) - { - /* Since the middle-end checks the type when doing a build2, we - need to build the tree in pieces. This built tree will never - get out of the front-end as we replace it when instantiating - the template. */ - tree tmp = build2 (resultcode, - build_type ? build_type : result_type, - NULL_TREE, op1); - TREE_OPERAND (tmp, 0) = op0; - return tmp; - } - - if (arithmetic_types_p) - { - bool first_complex = (code0 == COMPLEX_TYPE); - bool second_complex = (code1 == COMPLEX_TYPE); - int none_complex = (!first_complex && !second_complex); - - /* Adapted from patch for c/24581. */ - if (first_complex != second_complex - && (code == PLUS_EXPR - || code == MINUS_EXPR - || code == MULT_EXPR - || (code == TRUNC_DIV_EXPR && first_complex)) - && TREE_CODE (TREE_TYPE (result_type)) == REAL_TYPE - && flag_signed_zeros) - { - /* An operation on mixed real/complex operands must be - handled specially, but the language-independent code can - more easily optimize the plain complex arithmetic if - -fno-signed-zeros. */ - tree real_type = TREE_TYPE (result_type); - tree real, imag; - if (first_complex) - { - if (TREE_TYPE (op0) != result_type) - op0 = cp_convert_and_check (result_type, op0, complain); - if (TREE_TYPE (op1) != real_type) - op1 = cp_convert_and_check (real_type, op1, complain); - } - else - { - if (TREE_TYPE (op0) != real_type) - op0 = cp_convert_and_check (real_type, op0, complain); - if (TREE_TYPE (op1) != result_type) - op1 = cp_convert_and_check (result_type, op1, complain); - } - if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK) - return error_mark_node; - if (first_complex) - { - op0 = save_expr (op0); - real = cp_build_unary_op (REALPART_EXPR, op0, 1, complain); - imag = cp_build_unary_op (IMAGPART_EXPR, op0, 1, complain); - switch (code) - { - case MULT_EXPR: - case TRUNC_DIV_EXPR: - op1 = save_expr (op1); - imag = build2 (resultcode, real_type, imag, op1); - /* Fall through. */ - case PLUS_EXPR: - case MINUS_EXPR: - real = build2 (resultcode, real_type, real, op1); - break; - default: - gcc_unreachable(); - } - } - else - { - op1 = save_expr (op1); - real = cp_build_unary_op (REALPART_EXPR, op1, 1, complain); - imag = cp_build_unary_op (IMAGPART_EXPR, op1, 1, complain); - switch (code) - { - case MULT_EXPR: - op0 = save_expr (op0); - imag = build2 (resultcode, real_type, op0, imag); - /* Fall through. */ - case PLUS_EXPR: - real = build2 (resultcode, real_type, op0, real); - break; - case MINUS_EXPR: - real = build2 (resultcode, real_type, op0, real); - imag = build1 (NEGATE_EXPR, real_type, imag); - break; - default: - gcc_unreachable(); - } - } - real = fold_if_not_in_template (real); - imag = fold_if_not_in_template (imag); - result = build2 (COMPLEX_EXPR, result_type, real, imag); - result = fold_if_not_in_template (result); - return result; - } - - /* For certain operations (which identify themselves by shorten != 0) - if both args were extended from the same smaller type, - do the arithmetic in that type and then extend. - - shorten !=0 and !=1 indicates a bitwise operation. - For them, this optimization is safe only if - both args are zero-extended or both are sign-extended. - Otherwise, we might change the result. - E.g., (short)-1 | (unsigned short)-1 is (int)-1 - but calculated in (unsigned short) it would be (unsigned short)-1. */ - - if (shorten && none_complex) - { - final_type = result_type; - result_type = shorten_binary_op (result_type, op0, op1, - shorten == -1); - } - - /* Comparison operations are shortened too but differently. - They identify themselves by setting short_compare = 1. */ - - if (short_compare) - { - /* Don't write &op0, etc., because that would prevent op0 - from being kept in a register. - Instead, make copies of the our local variables and - pass the copies by reference, then copy them back afterward. */ - tree xop0 = op0, xop1 = op1, xresult_type = result_type; - enum tree_code xresultcode = resultcode; - tree val - = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode); - if (val != 0) - return cp_convert (boolean_type_node, val, complain); - op0 = xop0, op1 = xop1; - converted = 1; - resultcode = xresultcode; - } - - if ((short_compare || code == MIN_EXPR || code == MAX_EXPR) - && warn_sign_compare - /* Do not warn until the template is instantiated; we cannot - bound the ranges of the arguments until that point. */ - && !processing_template_decl - && (complain & tf_warning) - && c_inhibit_evaluation_warnings == 0 - /* Even unsigned enum types promote to signed int. We don't - want to issue -Wsign-compare warnings for this case. */ - && !enum_cast_to_int (orig_op0) - && !enum_cast_to_int (orig_op1)) - { - tree oop0 = maybe_constant_value (orig_op0); - tree oop1 = maybe_constant_value (orig_op1); - - if (TREE_CODE (oop0) != INTEGER_CST) - oop0 = orig_op0; - if (TREE_CODE (oop1) != INTEGER_CST) - oop1 = orig_op1; - warn_for_sign_compare (location, oop0, oop1, op0, op1, - result_type, resultcode); - } - } - - /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE. - Then the expression will be built. - It will be given type FINAL_TYPE if that is nonzero; - otherwise, it will be given type RESULT_TYPE. */ - if (! converted) - { - if (TREE_TYPE (op0) != result_type) - op0 = cp_convert_and_check (result_type, op0, complain); - if (TREE_TYPE (op1) != result_type) - op1 = cp_convert_and_check (result_type, op1, complain); - - if (op0 == error_mark_node || op1 == error_mark_node) - return error_mark_node; - } - - if (build_type == NULL_TREE) - build_type = result_type; - - result = build2 (resultcode, build_type, op0, op1); - result = fold_if_not_in_template (result); - if (final_type != 0) - result = cp_convert (final_type, result, complain); - - if (TREE_OVERFLOW_P (result) - && !TREE_OVERFLOW_P (op0) - && !TREE_OVERFLOW_P (op1)) - overflow_warning (location, result); - - return result; -} - -/* Return a tree for the sum or difference (RESULTCODE says which) - of pointer PTROP and integer INTOP. */ - -static tree -cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop) -{ - tree res_type = TREE_TYPE (ptrop); - - /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type) - in certain circumstance (when it's valid to do so). So we need - to make sure it's complete. We don't need to check here, if we - can actually complete it at all, as those checks will be done in - pointer_int_sum() anyway. */ - complete_type (TREE_TYPE (res_type)); - - return pointer_int_sum (input_location, resultcode, ptrop, - fold_if_not_in_template (intop)); -} - -/* Return a tree for the difference of pointers OP0 and OP1. - The resulting tree has type int. */ - -static tree -pointer_diff (tree op0, tree op1, tree ptrtype, tsubst_flags_t complain) -{ - tree result; - tree restype = ptrdiff_type_node; - tree target_type = TREE_TYPE (ptrtype); - - if (!complete_type_or_else (target_type, NULL_TREE)) - return error_mark_node; - - if (TREE_CODE (target_type) == VOID_TYPE) - { - if (complain & tf_error) - permerror (input_location, "ISO C++ forbids using pointer of " - "type %<void *%> in subtraction"); - else - return error_mark_node; - } - if (TREE_CODE (target_type) == FUNCTION_TYPE) - { - if (complain & tf_error) - permerror (input_location, "ISO C++ forbids using pointer to " - "a function in subtraction"); - else - return error_mark_node; - } - if (TREE_CODE (target_type) == METHOD_TYPE) - { - if (complain & tf_error) - permerror (input_location, "ISO C++ forbids using pointer to " - "a method in subtraction"); - else - return error_mark_node; - } - - /* First do the subtraction as integers; - then drop through to build the divide operator. */ - - op0 = cp_build_binary_op (input_location, - MINUS_EXPR, - cp_convert (restype, op0, complain), - cp_convert (restype, op1, complain), - complain); - - /* This generates an error if op1 is a pointer to an incomplete type. */ - if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1)))) - { - if (complain & tf_error) - error ("invalid use of a pointer to an incomplete type in " - "pointer arithmetic"); - else - return error_mark_node; - } - - op1 = (TYPE_PTROB_P (ptrtype) - ? size_in_bytes (target_type) - : integer_one_node); - - /* Do the division. */ - - result = build2 (EXACT_DIV_EXPR, restype, op0, - cp_convert (restype, op1, complain)); - return fold_if_not_in_template (result); -} - -/* Construct and perhaps optimize a tree representation - for a unary operation. CODE, a tree_code, specifies the operation - and XARG is the operand. */ - -tree -build_x_unary_op (location_t loc, enum tree_code code, tree xarg, - tsubst_flags_t complain) -{ - tree orig_expr = xarg; - tree exp; - int ptrmem = 0; - - if (processing_template_decl) - { - if (type_dependent_expression_p (xarg)) - return build_min_nt_loc (loc, code, xarg, NULL_TREE); - - xarg = build_non_dependent_expr (xarg); - } - - exp = NULL_TREE; - - /* [expr.unary.op] says: - - The address of an object of incomplete type can be taken. - - (And is just the ordinary address operator, not an overloaded - "operator &".) However, if the type is a template - specialization, we must complete the type at this point so that - an overloaded "operator &" will be available if required. */ - if (code == ADDR_EXPR - && TREE_CODE (xarg) != TEMPLATE_ID_EXPR - && ((CLASS_TYPE_P (TREE_TYPE (xarg)) - && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg)))) - || (TREE_CODE (xarg) == OFFSET_REF))) - /* Don't look for a function. */; - else - exp = build_new_op (loc, code, LOOKUP_NORMAL, xarg, NULL_TREE, - NULL_TREE, /*overload=*/NULL, complain); - if (!exp && code == ADDR_EXPR) - { - if (is_overloaded_fn (xarg)) - { - tree fn = get_first_fn (xarg); - if (DECL_CONSTRUCTOR_P (fn) || DECL_DESTRUCTOR_P (fn)) - { - error (DECL_CONSTRUCTOR_P (fn) - ? G_("taking address of constructor %qE") - : G_("taking address of destructor %qE"), - xarg); - return error_mark_node; - } - } - - /* A pointer to member-function can be formed only by saying - &X::mf. */ - if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE - && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg))) - { - if (TREE_CODE (xarg) != OFFSET_REF - || !TYPE_P (TREE_OPERAND (xarg, 0))) - { - error ("invalid use of %qE to form a pointer-to-member-function", - xarg); - if (TREE_CODE (xarg) != OFFSET_REF) - inform (input_location, " a qualified-id is required"); - return error_mark_node; - } - else - { - error ("parentheses around %qE cannot be used to form a" - " pointer-to-member-function", - xarg); - PTRMEM_OK_P (xarg) = 1; - } - } - - if (TREE_CODE (xarg) == OFFSET_REF) - { - ptrmem = PTRMEM_OK_P (xarg); - - if (!ptrmem && !flag_ms_extensions - && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE) - { - /* A single non-static member, make sure we don't allow a - pointer-to-member. */ - xarg = build2 (OFFSET_REF, TREE_TYPE (xarg), - TREE_OPERAND (xarg, 0), - ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE)); - PTRMEM_OK_P (xarg) = ptrmem; - } - } - - exp = cp_build_addr_expr_strict (xarg, complain); - } - - if (processing_template_decl && exp != error_mark_node) - exp = build_min_non_dep (code, exp, orig_expr, - /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE); - if (TREE_CODE (exp) == ADDR_EXPR) - PTRMEM_OK_P (exp) = ptrmem; - return exp; -} - -/* Like c_common_truthvalue_conversion, but handle pointer-to-member - constants, where a null value is represented by an INTEGER_CST of - -1. */ - -tree -cp_truthvalue_conversion (tree expr) -{ - tree type = TREE_TYPE (expr); - if (TYPE_PTRDATAMEM_P (type)) - return build_binary_op (EXPR_LOCATION (expr), - NE_EXPR, expr, nullptr_node, 1); - else if (TYPE_PTR_P (type) || TYPE_PTRMEMFUNC_P (type)) - { - /* With -Wzero-as-null-pointer-constant do not warn for an - 'if (p)' or a 'while (!p)', where p is a pointer. */ - tree ret; - ++c_inhibit_evaluation_warnings; - ret = c_common_truthvalue_conversion (input_location, expr); - --c_inhibit_evaluation_warnings; - return ret; - } - else - return c_common_truthvalue_conversion (input_location, expr); -} - -/* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */ - -tree -condition_conversion (tree expr) -{ - tree t; - if (processing_template_decl) - return expr; - t = perform_implicit_conversion_flags (boolean_type_node, expr, - tf_warning_or_error, LOOKUP_NORMAL); - t = fold_build_cleanup_point_expr (boolean_type_node, t); - return t; -} - -/* Returns the address of T. This function will fold away - ADDR_EXPR of INDIRECT_REF. */ - -tree -build_address (tree t) -{ - if (error_operand_p (t) || !cxx_mark_addressable (t)) - return error_mark_node; - t = build_fold_addr_expr (t); - if (TREE_CODE (t) != ADDR_EXPR) - t = rvalue (t); - return t; -} - -/* Returns the address of T with type TYPE. */ - -tree -build_typed_address (tree t, tree type) -{ - if (error_operand_p (t) || !cxx_mark_addressable (t)) - return error_mark_node; - t = build_fold_addr_expr_with_type (t, type); - if (TREE_CODE (t) != ADDR_EXPR) - t = rvalue (t); - return t; -} - -/* Return a NOP_EXPR converting EXPR to TYPE. */ - -tree -build_nop (tree type, tree expr) -{ - if (type == error_mark_node || error_operand_p (expr)) - return expr; - return build1 (NOP_EXPR, type, expr); -} - -/* Take the address of ARG, whatever that means under C++ semantics. - If STRICT_LVALUE is true, require an lvalue; otherwise, allow xvalues - and class rvalues as well. - - Nothing should call this function directly; instead, callers should use - cp_build_addr_expr or cp_build_addr_expr_strict. */ - -static tree -cp_build_addr_expr_1 (tree arg, bool strict_lvalue, tsubst_flags_t complain) -{ - tree argtype; - tree val; - - if (!arg || error_operand_p (arg)) - return error_mark_node; - - arg = mark_lvalue_use (arg); - argtype = lvalue_type (arg); - - gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE - || !IDENTIFIER_OPNAME_P (arg)); - - if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg) - && !really_overloaded_fn (TREE_OPERAND (arg, 1))) - { - /* They're trying to take the address of a unique non-static - member function. This is ill-formed (except in MS-land), - but let's try to DTRT. - Note: We only handle unique functions here because we don't - want to complain if there's a static overload; non-unique - cases will be handled by instantiate_type. But we need to - handle this case here to allow casts on the resulting PMF. - We could defer this in non-MS mode, but it's easier to give - a useful error here. */ - - /* Inside constant member functions, the `this' pointer - contains an extra const qualifier. TYPE_MAIN_VARIANT - is used here to remove this const from the diagnostics - and the created OFFSET_REF. */ - tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0))); - tree fn = get_first_fn (TREE_OPERAND (arg, 1)); - mark_used (fn); - - if (! flag_ms_extensions) - { - tree name = DECL_NAME (fn); - if (!(complain & tf_error)) - return error_mark_node; - else if (current_class_type - && TREE_OPERAND (arg, 0) == current_class_ref) - /* An expression like &memfn. */ - permerror (input_location, "ISO C++ forbids taking the address of an unqualified" - " or parenthesized non-static member function to form" - " a pointer to member function. Say %<&%T::%D%>", - base, name); - else - permerror (input_location, "ISO C++ forbids taking the address of a bound member" - " function to form a pointer to member function." - " Say %<&%T::%D%>", - base, name); - } - arg = build_offset_ref (base, fn, /*address_p=*/true, complain); - } - - /* Uninstantiated types are all functions. Taking the - address of a function is a no-op, so just return the - argument. */ - if (type_unknown_p (arg)) - return build1 (ADDR_EXPR, unknown_type_node, arg); - - if (TREE_CODE (arg) == OFFSET_REF) - /* We want a pointer to member; bypass all the code for actually taking - the address of something. */ - goto offset_ref; - - /* Anything not already handled and not a true memory reference - is an error. */ - if (TREE_CODE (argtype) != FUNCTION_TYPE - && TREE_CODE (argtype) != METHOD_TYPE) - { - cp_lvalue_kind kind = lvalue_kind (arg); - if (kind == clk_none) - { - if (complain & tf_error) - lvalue_error (input_location, lv_addressof); - return error_mark_node; - } - if (strict_lvalue && (kind & (clk_rvalueref|clk_class))) - { - if (!(complain & tf_error)) - return error_mark_node; - if (kind & clk_class) - /* Make this a permerror because we used to accept it. */ - permerror (input_location, "taking address of temporary"); - else - error ("taking address of xvalue (rvalue reference)"); - } - } - - if (TREE_CODE (argtype) == REFERENCE_TYPE) - { - tree type = build_pointer_type (TREE_TYPE (argtype)); - arg = build1 (CONVERT_EXPR, type, arg); - return arg; - } - else if (pedantic && DECL_MAIN_P (arg)) - { - /* ARM $3.4 */ - /* Apparently a lot of autoconf scripts for C++ packages do this, - so only complain if -Wpedantic. */ - if (complain & (flag_pedantic_errors ? tf_error : tf_warning)) - pedwarn (input_location, OPT_Wpedantic, - "ISO C++ forbids taking address of function %<::main%>"); - else if (flag_pedantic_errors) - return error_mark_node; - } - - /* Let &* cancel out to simplify resulting code. */ - if (TREE_CODE (arg) == INDIRECT_REF) - { - /* We don't need to have `current_class_ptr' wrapped in a - NON_LVALUE_EXPR node. */ - if (arg == current_class_ref) - return current_class_ptr; - - arg = TREE_OPERAND (arg, 0); - if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE) - { - tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg))); - arg = build1 (CONVERT_EXPR, type, arg); - } - else - /* Don't let this be an lvalue. */ - arg = rvalue (arg); - return arg; - } - - /* ??? Cope with user tricks that amount to offsetof. */ - if (TREE_CODE (argtype) != FUNCTION_TYPE - && TREE_CODE (argtype) != METHOD_TYPE - && argtype != unknown_type_node - && (val = get_base_address (arg)) - && COMPLETE_TYPE_P (TREE_TYPE (val)) - && TREE_CODE (val) == INDIRECT_REF - && TREE_CONSTANT (TREE_OPERAND (val, 0))) - { - tree type = build_pointer_type (argtype); - return fold_convert (type, fold_offsetof_1 (arg)); - } - - /* Handle complex lvalues (when permitted) - by reduction to simpler cases. */ - val = unary_complex_lvalue (ADDR_EXPR, arg); - if (val != 0) - return val; - - switch (TREE_CODE (arg)) - { - CASE_CONVERT: - case FLOAT_EXPR: - case FIX_TRUNC_EXPR: - /* Even if we're not being pedantic, we cannot allow this - extension when we're instantiating in a SFINAE - context. */ - if (! lvalue_p (arg) && complain == tf_none) - { - if (complain & tf_error) - permerror (input_location, "ISO C++ forbids taking the address of a cast to a non-lvalue expression"); - else - return error_mark_node; - } - break; - - case BASELINK: - arg = BASELINK_FUNCTIONS (arg); - /* Fall through. */ - - case OVERLOAD: - arg = OVL_CURRENT (arg); - break; - - case OFFSET_REF: - offset_ref: - /* Turn a reference to a non-static data member into a - pointer-to-member. */ - { - tree type; - tree t; - - gcc_assert (PTRMEM_OK_P (arg)); - - t = TREE_OPERAND (arg, 1); - if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE) - { - if (complain & tf_error) - error ("cannot create pointer to reference member %qD", t); - return error_mark_node; - } - - type = build_ptrmem_type (context_for_name_lookup (t), - TREE_TYPE (t)); - t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1)); - return t; - } - - default: - break; - } - - if (argtype != error_mark_node) - argtype = build_pointer_type (argtype); - - /* In a template, we are processing a non-dependent expression - so we can just form an ADDR_EXPR with the correct type. */ - if (processing_template_decl || TREE_CODE (arg) != COMPONENT_REF) - { - val = build_address (arg); - if (TREE_CODE (arg) == OFFSET_REF) - PTRMEM_OK_P (val) = PTRMEM_OK_P (arg); - } - else if (BASELINK_P (TREE_OPERAND (arg, 1))) - { - tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1)); - - /* We can only get here with a single static member - function. */ - gcc_assert (TREE_CODE (fn) == FUNCTION_DECL - && DECL_STATIC_FUNCTION_P (fn)); - mark_used (fn); - val = build_address (fn); - if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0))) - /* Do not lose object's side effects. */ - val = build2 (COMPOUND_EXPR, TREE_TYPE (val), - TREE_OPERAND (arg, 0), val); - } - else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1))) - { - if (complain & tf_error) - error ("attempt to take address of bit-field structure member %qD", - TREE_OPERAND (arg, 1)); - return error_mark_node; - } - else - { - tree object = TREE_OPERAND (arg, 0); - tree field = TREE_OPERAND (arg, 1); - gcc_assert (same_type_ignoring_top_level_qualifiers_p - (TREE_TYPE (object), decl_type_context (field))); - val = build_address (arg); - } - - if (TREE_CODE (argtype) == POINTER_TYPE - && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE) - { - build_ptrmemfunc_type (argtype); - val = build_ptrmemfunc (argtype, val, 0, - /*c_cast_p=*/false, - complain); - } - - return val; -} - -/* Take the address of ARG if it has one, even if it's an rvalue. */ - -tree -cp_build_addr_expr (tree arg, tsubst_flags_t complain) -{ - return cp_build_addr_expr_1 (arg, 0, complain); -} - -/* Take the address of ARG, but only if it's an lvalue. */ - -tree -cp_build_addr_expr_strict (tree arg, tsubst_flags_t complain) -{ - return cp_build_addr_expr_1 (arg, 1, complain); -} - -/* C++: Must handle pointers to members. - - Perhaps type instantiation should be extended to handle conversion - from aggregates to types we don't yet know we want? (Or are those - cases typically errors which should be reported?) - - NOCONVERT nonzero suppresses the default promotions - (such as from short to int). */ - -tree -cp_build_unary_op (enum tree_code code, tree xarg, int noconvert, - tsubst_flags_t complain) -{ - /* No default_conversion here. It causes trouble for ADDR_EXPR. */ - tree arg = xarg; - tree argtype = 0; - const char *errstring = NULL; - tree val; - const char *invalid_op_diag; - - if (!arg || error_operand_p (arg)) - return error_mark_node; - - if ((invalid_op_diag - = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR - ? CONVERT_EXPR - : code), - TREE_TYPE (xarg)))) - { - error (invalid_op_diag); - return error_mark_node; - } - - switch (code) - { - case UNARY_PLUS_EXPR: - case NEGATE_EXPR: - { - int flags = WANT_ARITH | WANT_ENUM; - /* Unary plus (but not unary minus) is allowed on pointers. */ - if (code == UNARY_PLUS_EXPR) - flags |= WANT_POINTER; - arg = build_expr_type_conversion (flags, arg, true); - if (!arg) - errstring = (code == NEGATE_EXPR - ? _("wrong type argument to unary minus") - : _("wrong type argument to unary plus")); - else - { - if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg))) - arg = cp_perform_integral_promotions (arg, complain); - - /* Make sure the result is not an lvalue: a unary plus or minus - expression is always a rvalue. */ - arg = rvalue (arg); - } - } - break; - - case BIT_NOT_EXPR: - if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE) - { - code = CONJ_EXPR; - if (!noconvert) - { - arg = cp_default_conversion (arg, complain); - if (arg == error_mark_node) - return error_mark_node; - } - } - else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM - | WANT_VECTOR_OR_COMPLEX, - arg, true))) - errstring = _("wrong type argument to bit-complement"); - else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg))) - arg = cp_perform_integral_promotions (arg, complain); - break; - - case ABS_EXPR: - if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true))) - errstring = _("wrong type argument to abs"); - else if (!noconvert) - { - arg = cp_default_conversion (arg, complain); - if (arg == error_mark_node) - return error_mark_node; - } - break; - - case CONJ_EXPR: - /* Conjugating a real value is a no-op, but allow it anyway. */ - if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true))) - errstring = _("wrong type argument to conjugation"); - else if (!noconvert) - { - arg = cp_default_conversion (arg, complain); - if (arg == error_mark_node) - return error_mark_node; - } - break; - - case TRUTH_NOT_EXPR: - arg = perform_implicit_conversion (boolean_type_node, arg, - complain); - val = invert_truthvalue_loc (input_location, arg); - if (arg != error_mark_node) - return val; - errstring = _("in argument to unary !"); - break; - - case NOP_EXPR: - break; - - case REALPART_EXPR: - case IMAGPART_EXPR: - arg = build_real_imag_expr (input_location, code, arg); - if (arg == error_mark_node) - return arg; - else - return fold_if_not_in_template (arg); - - case PREINCREMENT_EXPR: - case POSTINCREMENT_EXPR: - case PREDECREMENT_EXPR: - case POSTDECREMENT_EXPR: - /* Handle complex lvalues (when permitted) - by reduction to simpler cases. */ - - val = unary_complex_lvalue (code, arg); - if (val != 0) - return val; - - arg = mark_lvalue_use (arg); - - /* Increment or decrement the real part of the value, - and don't change the imaginary part. */ - if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE) - { - tree real, imag; - - arg = stabilize_reference (arg); - real = cp_build_unary_op (REALPART_EXPR, arg, 1, complain); - imag = cp_build_unary_op (IMAGPART_EXPR, arg, 1, complain); - real = cp_build_unary_op (code, real, 1, complain); - if (real == error_mark_node || imag == error_mark_node) - return error_mark_node; - return build2 (COMPLEX_EXPR, TREE_TYPE (arg), - real, imag); - } - - /* Report invalid types. */ - - if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER, - arg, true))) - { - if (code == PREINCREMENT_EXPR) - errstring = _("no pre-increment operator for type"); - else if (code == POSTINCREMENT_EXPR) - errstring = _("no post-increment operator for type"); - else if (code == PREDECREMENT_EXPR) - errstring = _("no pre-decrement operator for type"); - else - errstring = _("no post-decrement operator for type"); - break; - } - else if (arg == error_mark_node) - return error_mark_node; - - /* Report something read-only. */ - - if (CP_TYPE_CONST_P (TREE_TYPE (arg)) - || TREE_READONLY (arg)) - { - if (complain & tf_error) - cxx_readonly_error (arg, ((code == PREINCREMENT_EXPR - || code == POSTINCREMENT_EXPR) - ? lv_increment : lv_decrement)); - else - return error_mark_node; - } - - { - tree inc; - tree declared_type = unlowered_expr_type (arg); - - argtype = TREE_TYPE (arg); - - /* ARM $5.2.5 last annotation says this should be forbidden. */ - if (TREE_CODE (argtype) == ENUMERAL_TYPE) - { - if (complain & tf_error) - permerror (input_location, (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) - ? G_("ISO C++ forbids incrementing an enum") - : G_("ISO C++ forbids decrementing an enum")); - else - return error_mark_node; - } - - /* Compute the increment. */ - - if (TREE_CODE (argtype) == POINTER_TYPE) - { - tree type = complete_type (TREE_TYPE (argtype)); - - if (!COMPLETE_OR_VOID_TYPE_P (type)) - { - if (complain & tf_error) - error (((code == PREINCREMENT_EXPR - || code == POSTINCREMENT_EXPR)) - ? G_("cannot increment a pointer to incomplete type %qT") - : G_("cannot decrement a pointer to incomplete type %qT"), - TREE_TYPE (argtype)); - else - return error_mark_node; - } - else if ((pedantic || warn_pointer_arith) - && !TYPE_PTROB_P (argtype)) - { - if (complain & tf_error) - permerror (input_location, (code == PREINCREMENT_EXPR - || code == POSTINCREMENT_EXPR) - ? G_("ISO C++ forbids incrementing a pointer of type %qT") - : G_("ISO C++ forbids decrementing a pointer of type %qT"), - argtype); - else - return error_mark_node; - } - - inc = cxx_sizeof_nowarn (TREE_TYPE (argtype)); - } - else - inc = integer_one_node; - - inc = cp_convert (argtype, inc, complain); - - /* If 'arg' is an Objective-C PROPERTY_REF expression, then we - need to ask Objective-C to build the increment or decrement - expression for it. */ - if (objc_is_property_ref (arg)) - return objc_build_incr_expr_for_property_ref (input_location, code, - arg, inc); - - /* Complain about anything else that is not a true lvalue. */ - if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR - || code == POSTINCREMENT_EXPR) - ? lv_increment : lv_decrement), - complain)) - return error_mark_node; - - /* Forbid using -- on `bool'. */ - if (TREE_CODE (declared_type) == BOOLEAN_TYPE) - { - if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR) - { - if (complain & tf_error) - error ("invalid use of Boolean expression as operand " - "to %<operator--%>"); - return error_mark_node; - } - val = boolean_increment (code, arg); - } - else if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR) - /* An rvalue has no cv-qualifiers. */ - val = build2 (code, cv_unqualified (TREE_TYPE (arg)), arg, inc); - else - val = build2 (code, TREE_TYPE (arg), arg, inc); - - TREE_SIDE_EFFECTS (val) = 1; - return val; - } - - case ADDR_EXPR: - /* Note that this operation never does default_conversion - regardless of NOCONVERT. */ - return cp_build_addr_expr (arg, complain); - - default: - break; - } - - if (!errstring) - { - if (argtype == 0) - argtype = TREE_TYPE (arg); - return fold_if_not_in_template (build1 (code, argtype, arg)); - } - - if (complain & tf_error) - error ("%s", errstring); - return error_mark_node; -} - -/* Hook for the c-common bits that build a unary op. */ -tree -build_unary_op (location_t /*location*/, - enum tree_code code, tree xarg, int noconvert) -{ - return cp_build_unary_op (code, xarg, noconvert, tf_warning_or_error); -} - -/* Apply unary lvalue-demanding operator CODE to the expression ARG - for certain kinds of expressions which are not really lvalues - but which we can accept as lvalues. - - If ARG is not a kind of expression we can handle, return - NULL_TREE. */ - -tree -unary_complex_lvalue (enum tree_code code, tree arg) -{ - /* Inside a template, making these kinds of adjustments is - pointless; we are only concerned with the type of the - expression. */ - if (processing_template_decl) - return NULL_TREE; - - /* Handle (a, b) used as an "lvalue". */ - if (TREE_CODE (arg) == COMPOUND_EXPR) - { - tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 1), 0, - tf_warning_or_error); - return build2 (COMPOUND_EXPR, TREE_TYPE (real_result), - TREE_OPERAND (arg, 0), real_result); - } - - /* Handle (a ? b : c) used as an "lvalue". */ - if (TREE_CODE (arg) == COND_EXPR - || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR) - return rationalize_conditional_expr (code, arg, tf_warning_or_error); - - /* Handle (a = b), (++a), and (--a) used as an "lvalue". */ - if (TREE_CODE (arg) == MODIFY_EXPR - || TREE_CODE (arg) == PREINCREMENT_EXPR - || TREE_CODE (arg) == PREDECREMENT_EXPR) - { - tree lvalue = TREE_OPERAND (arg, 0); - if (TREE_SIDE_EFFECTS (lvalue)) - { - lvalue = stabilize_reference (lvalue); - arg = build2 (TREE_CODE (arg), TREE_TYPE (arg), - lvalue, TREE_OPERAND (arg, 1)); - } - return unary_complex_lvalue - (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue)); - } - - if (code != ADDR_EXPR) - return NULL_TREE; - - /* Handle (a = b) used as an "lvalue" for `&'. */ - if (TREE_CODE (arg) == MODIFY_EXPR - || TREE_CODE (arg) == INIT_EXPR) - { - tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 0), 0, - tf_warning_or_error); - arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result), - arg, real_result); - TREE_NO_WARNING (arg) = 1; - return arg; - } - - if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE - || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE - || TREE_CODE (arg) == OFFSET_REF) - return NULL_TREE; - - /* We permit compiler to make function calls returning - objects of aggregate type look like lvalues. */ - { - tree targ = arg; - - if (TREE_CODE (targ) == SAVE_EXPR) - targ = TREE_OPERAND (targ, 0); - - if (TREE_CODE (targ) == CALL_EXPR && MAYBE_CLASS_TYPE_P (TREE_TYPE (targ))) - { - if (TREE_CODE (arg) == SAVE_EXPR) - targ = arg; - else - targ = build_cplus_new (TREE_TYPE (arg), arg, tf_warning_or_error); - return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ); - } - - if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF) - return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)), - TREE_OPERAND (targ, 0), current_function_decl, NULL); - } - - /* Don't let anything else be handled specially. */ - return NULL_TREE; -} - -/* Mark EXP saying that we need to be able to take the - address of it; it should not be allocated in a register. - Value is true if successful. - - C++: we do not allow `current_class_ptr' to be addressable. */ - -bool -cxx_mark_addressable (tree exp) -{ - tree x = exp; - - while (1) - switch (TREE_CODE (x)) - { - case ADDR_EXPR: - case COMPONENT_REF: - case ARRAY_REF: - case REALPART_EXPR: - case IMAGPART_EXPR: - x = TREE_OPERAND (x, 0); - break; - - case PARM_DECL: - if (x == current_class_ptr) - { - error ("cannot take the address of %<this%>, which is an rvalue expression"); - TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */ - return true; - } - /* Fall through. */ - - case VAR_DECL: - /* Caller should not be trying to mark initialized - constant fields addressable. */ - gcc_assert (DECL_LANG_SPECIFIC (x) == 0 - || DECL_IN_AGGR_P (x) == 0 - || TREE_STATIC (x) - || DECL_EXTERNAL (x)); - /* Fall through. */ - - case RESULT_DECL: - if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x) - && !DECL_ARTIFICIAL (x)) - { - if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x)) - { - error - ("address of explicit register variable %qD requested", x); - return false; - } - else if (extra_warnings) - warning - (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x); - } - TREE_ADDRESSABLE (x) = 1; - return true; - - case CONST_DECL: - case FUNCTION_DECL: - TREE_ADDRESSABLE (x) = 1; - return true; - - case CONSTRUCTOR: - TREE_ADDRESSABLE (x) = 1; - return true; - - case TARGET_EXPR: - TREE_ADDRESSABLE (x) = 1; - cxx_mark_addressable (TREE_OPERAND (x, 0)); - return true; - - default: - return true; - } -} - -/* Build and return a conditional expression IFEXP ? OP1 : OP2. */ - -tree -build_x_conditional_expr (location_t loc, tree ifexp, tree op1, tree op2, - tsubst_flags_t complain) -{ - tree orig_ifexp = ifexp; - tree orig_op1 = op1; - tree orig_op2 = op2; - tree expr; - - if (processing_template_decl) - { - /* The standard says that the expression is type-dependent if - IFEXP is type-dependent, even though the eventual type of the - expression doesn't dependent on IFEXP. */ - if (type_dependent_expression_p (ifexp) - /* As a GNU extension, the middle operand may be omitted. */ - || (op1 && type_dependent_expression_p (op1)) - || type_dependent_expression_p (op2)) - return build_min_nt_loc (loc, COND_EXPR, ifexp, op1, op2); - ifexp = build_non_dependent_expr (ifexp); - if (op1) - op1 = build_non_dependent_expr (op1); - op2 = build_non_dependent_expr (op2); - } - - expr = build_conditional_expr (ifexp, op1, op2, complain); - if (processing_template_decl && expr != error_mark_node - && TREE_CODE (expr) != VEC_COND_EXPR) - { - tree min = build_min_non_dep (COND_EXPR, expr, - orig_ifexp, orig_op1, orig_op2); - /* In C++11, remember that the result is an lvalue or xvalue. - In C++98, lvalue_kind can just assume lvalue in a template. */ - if (cxx_dialect >= cxx0x - && lvalue_or_rvalue_with_address_p (expr) - && !lvalue_or_rvalue_with_address_p (min)) - TREE_TYPE (min) = cp_build_reference_type (TREE_TYPE (min), - !real_lvalue_p (expr)); - expr = convert_from_reference (min); - } - return expr; -} - -/* Given a list of expressions, return a compound expression - that performs them all and returns the value of the last of them. */ - -tree -build_x_compound_expr_from_list (tree list, expr_list_kind exp, - tsubst_flags_t complain) -{ - tree expr = TREE_VALUE (list); - - if (BRACE_ENCLOSED_INITIALIZER_P (expr) - && !CONSTRUCTOR_IS_DIRECT_INIT (expr)) - { - if (complain & tf_error) - pedwarn (EXPR_LOC_OR_HERE (expr), 0, "list-initializer for " - "non-class type must not be parenthesized"); - else - return error_mark_node; - } - - if (TREE_CHAIN (list)) - { - if (complain & tf_error) - switch (exp) - { - case ELK_INIT: - permerror (input_location, "expression list treated as compound " - "expression in initializer"); - break; - case ELK_MEM_INIT: - permerror (input_location, "expression list treated as compound " - "expression in mem-initializer"); - break; - case ELK_FUNC_CAST: - permerror (input_location, "expression list treated as compound " - "expression in functional cast"); - break; - default: - gcc_unreachable (); - } - else - return error_mark_node; - - for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list)) - expr = build_x_compound_expr (EXPR_LOCATION (TREE_VALUE (list)), - expr, TREE_VALUE (list), complain); - } - - return expr; -} - -/* Like build_x_compound_expr_from_list, but using a VEC. */ - -tree -build_x_compound_expr_from_vec (vec<tree, va_gc> *vec, const char *msg, - tsubst_flags_t complain) -{ - if (vec_safe_is_empty (vec)) - return NULL_TREE; - else if (vec->length () == 1) - return (*vec)[0]; - else - { - tree expr; - unsigned int ix; - tree t; - - if (msg != NULL) - { - if (complain & tf_error) - permerror (input_location, - "%s expression list treated as compound expression", - msg); - else - return error_mark_node; - } - - expr = (*vec)[0]; - for (ix = 1; vec->iterate (ix, &t); ++ix) - expr = build_x_compound_expr (EXPR_LOCATION (t), expr, - t, complain); - - return expr; - } -} - -/* Handle overloading of the ',' operator when needed. */ - -tree -build_x_compound_expr (location_t loc, tree op1, tree op2, - tsubst_flags_t complain) -{ - tree result; - tree orig_op1 = op1; - tree orig_op2 = op2; - - if (processing_template_decl) - { - if (type_dependent_expression_p (op1) - || type_dependent_expression_p (op2)) - return build_min_nt_loc (loc, COMPOUND_EXPR, op1, op2); - op1 = build_non_dependent_expr (op1); - op2 = build_non_dependent_expr (op2); - } - - result = build_new_op (loc, COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, - NULL_TREE, /*overload=*/NULL, complain); - if (!result) - result = cp_build_compound_expr (op1, op2, complain); - - if (processing_template_decl && result != error_mark_node) - return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2); - - return result; -} - -/* Like cp_build_compound_expr, but for the c-common bits. */ - -tree -build_compound_expr (location_t /*loc*/, tree lhs, tree rhs) -{ - return cp_build_compound_expr (lhs, rhs, tf_warning_or_error); -} - -/* Build a compound expression. */ - -tree -cp_build_compound_expr (tree lhs, tree rhs, tsubst_flags_t complain) -{ - lhs = convert_to_void (lhs, ICV_LEFT_OF_COMMA, complain); - - if (lhs == error_mark_node || rhs == error_mark_node) - return error_mark_node; - - if (TREE_CODE (rhs) == TARGET_EXPR) - { - /* If the rhs is a TARGET_EXPR, then build the compound - expression inside the target_expr's initializer. This - helps the compiler to eliminate unnecessary temporaries. */ - tree init = TREE_OPERAND (rhs, 1); - - init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init); - TREE_OPERAND (rhs, 1) = init; - - return rhs; - } - - if (type_unknown_p (rhs)) - { - error ("no context to resolve type of %qE", rhs); - return error_mark_node; - } - - return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs); -} - -/* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE - casts away constness. CAST gives the type of cast. Returns true - if the cast is ill-formed, false if it is well-formed. - - ??? This function warns for casting away any qualifier not just - const. We would like to specify exactly what qualifiers are casted - away. -*/ - -static bool -check_for_casting_away_constness (tree src_type, tree dest_type, - enum tree_code cast, tsubst_flags_t complain) -{ - /* C-style casts are allowed to cast away constness. With - WARN_CAST_QUAL, we still want to issue a warning. */ - if (cast == CAST_EXPR && !warn_cast_qual) - return false; - - if (!casts_away_constness (src_type, dest_type, complain)) - return false; - - switch (cast) - { - case CAST_EXPR: - if (complain & tf_warning) - warning (OPT_Wcast_qual, - "cast from type %qT to type %qT casts away qualifiers", - src_type, dest_type); - return false; - - case STATIC_CAST_EXPR: - if (complain & tf_error) - error ("static_cast from type %qT to type %qT casts away qualifiers", - src_type, dest_type); - return true; - - case REINTERPRET_CAST_EXPR: - if (complain & tf_error) - error ("reinterpret_cast from type %qT to type %qT casts away qualifiers", - src_type, dest_type); - return true; - - default: - gcc_unreachable(); - } -} - -/* - Warns if the cast from expression EXPR to type TYPE is useless. - */ -void -maybe_warn_about_useless_cast (tree type, tree expr, tsubst_flags_t complain) -{ - if (warn_useless_cast - && complain & tf_warning - && c_inhibit_evaluation_warnings == 0) - { - if (REFERENCE_REF_P (expr)) - expr = TREE_OPERAND (expr, 0); - - if ((TREE_CODE (type) == REFERENCE_TYPE - && (TYPE_REF_IS_RVALUE (type) - ? xvalue_p (expr) : real_lvalue_p (expr)) - && same_type_p (TREE_TYPE (expr), TREE_TYPE (type))) - || same_type_p (TREE_TYPE (expr), type)) - warning (OPT_Wuseless_cast, "useless cast to type %qT", type); - } -} - -/* Convert EXPR (an expression with pointer-to-member type) to TYPE - (another pointer-to-member type in the same hierarchy) and return - the converted expression. If ALLOW_INVERSE_P is permitted, a - pointer-to-derived may be converted to pointer-to-base; otherwise, - only the other direction is permitted. If C_CAST_P is true, this - conversion is taking place as part of a C-style cast. */ - -tree -convert_ptrmem (tree type, tree expr, bool allow_inverse_p, - bool c_cast_p, tsubst_flags_t complain) -{ - if (TYPE_PTRDATAMEM_P (type)) - { - tree delta; - - if (TREE_CODE (expr) == PTRMEM_CST) - expr = cplus_expand_constant (expr); - delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)), - TYPE_PTRMEM_CLASS_TYPE (type), - allow_inverse_p, - c_cast_p, complain); - if (delta == error_mark_node) - return error_mark_node; - - if (!integer_zerop (delta)) - { - tree cond, op1, op2; - - cond = cp_build_binary_op (input_location, - EQ_EXPR, - expr, - build_int_cst (TREE_TYPE (expr), -1), - complain); - op1 = build_nop (ptrdiff_type_node, expr); - op2 = cp_build_binary_op (input_location, - PLUS_EXPR, op1, delta, - complain); - - expr = fold_build3_loc (input_location, - COND_EXPR, ptrdiff_type_node, cond, op1, op2); - - } - - return build_nop (type, expr); - } - else - return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr, - allow_inverse_p, c_cast_p, complain); -} - -/* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true, - this static_cast is being attempted as one of the possible casts - allowed by a C-style cast. (In that case, accessibility of base - classes is not considered, and it is OK to cast away - constness.) Return the result of the cast. *VALID_P is set to - indicate whether or not the cast was valid. */ - -static tree -build_static_cast_1 (tree type, tree expr, bool c_cast_p, - bool *valid_p, tsubst_flags_t complain) -{ - tree intype; - tree result; - cp_lvalue_kind clk; - - /* Assume the cast is valid. */ - *valid_p = true; - - intype = unlowered_expr_type (expr); - - /* Save casted types in the function's used types hash table. */ - used_types_insert (type); - - /* [expr.static.cast] - - An lvalue of type "cv1 B", where B is a class type, can be cast - to type "reference to cv2 D", where D is a class derived (clause - _class.derived_) from B, if a valid standard conversion from - "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the - same cv-qualification as, or greater cv-qualification than, cv1, - and B is not a virtual base class of D. */ - /* We check this case before checking the validity of "TYPE t = - EXPR;" below because for this case: - - struct B {}; - struct D : public B { D(const B&); }; - extern B& b; - void f() { static_cast<const D&>(b); } - - we want to avoid constructing a new D. The standard is not - completely clear about this issue, but our interpretation is - consistent with other compilers. */ - if (TREE_CODE (type) == REFERENCE_TYPE - && CLASS_TYPE_P (TREE_TYPE (type)) - && CLASS_TYPE_P (intype) - && (TYPE_REF_IS_RVALUE (type) || real_lvalue_p (expr)) - && DERIVED_FROM_P (intype, TREE_TYPE (type)) - && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)), - build_pointer_type (TYPE_MAIN_VARIANT - (TREE_TYPE (type))), - complain) - && (c_cast_p - || at_least_as_qualified_p (TREE_TYPE (type), intype))) - { - tree base; - - /* There is a standard conversion from "D*" to "B*" even if "B" - is ambiguous or inaccessible. If this is really a - static_cast, then we check both for inaccessibility and - ambiguity. However, if this is a static_cast being performed - because the user wrote a C-style cast, then accessibility is - not considered. */ - base = lookup_base (TREE_TYPE (type), intype, - c_cast_p ? ba_unique : ba_check, - NULL, complain); - - /* Convert from "B*" to "D*". This function will check that "B" - is not a virtual base of "D". */ - expr = build_base_path (MINUS_EXPR, build_address (expr), - base, /*nonnull=*/false, complain); - /* Convert the pointer to a reference -- but then remember that - there are no expressions with reference type in C++. - - We call rvalue so that there's an actual tree code - (NON_LVALUE_EXPR) for the static_cast; otherwise, if the operand - is a variable with the same type, the conversion would get folded - away, leaving just the variable and causing lvalue_kind to give - the wrong answer. */ - return convert_from_reference (rvalue (cp_fold_convert (type, expr))); - } - - /* "A glvalue of type cv1 T1 can be cast to type rvalue reference to - cv2 T2 if cv2 T2 is reference-compatible with cv1 T1 (8.5.3)." */ - if (TREE_CODE (type) == REFERENCE_TYPE - && TYPE_REF_IS_RVALUE (type) - && (clk = real_lvalue_p (expr)) - && reference_related_p (TREE_TYPE (type), intype) - && (c_cast_p || at_least_as_qualified_p (TREE_TYPE (type), intype))) - { - if (clk == clk_ordinary) - { - /* Handle the (non-bit-field) lvalue case here by casting to - lvalue reference and then changing it to an rvalue reference. - Casting an xvalue to rvalue reference will be handled by the - main code path. */ - tree lref = cp_build_reference_type (TREE_TYPE (type), false); - result = (perform_direct_initialization_if_possible - (lref, expr, c_cast_p, complain)); - result = cp_fold_convert (type, result); - /* Make sure we don't fold back down to a named rvalue reference, - because that would be an lvalue. */ - if (DECL_P (result)) - result = build1 (NON_LVALUE_EXPR, type, result); - return convert_from_reference (result); - } - else - /* For a bit-field or packed field, bind to a temporary. */ - expr = rvalue (expr); - } - - /* Resolve overloaded address here rather than once in - implicit_conversion and again in the inverse code below. */ - if (TYPE_PTRMEMFUNC_P (type) && type_unknown_p (expr)) - { - expr = instantiate_type (type, expr, complain); - intype = TREE_TYPE (expr); - } - - /* [expr.static.cast] - - Any expression can be explicitly converted to type cv void. */ - if (TREE_CODE (type) == VOID_TYPE) - return convert_to_void (expr, ICV_CAST, complain); - - /* [expr.static.cast] - - An expression e can be explicitly converted to a type T using a - static_cast of the form static_cast<T>(e) if the declaration T - t(e);" is well-formed, for some invented temporary variable - t. */ - result = perform_direct_initialization_if_possible (type, expr, - c_cast_p, complain); - if (result) - { - result = convert_from_reference (result); - - /* [expr.static.cast] - - If T is a reference type, the result is an lvalue; otherwise, - the result is an rvalue. */ - if (TREE_CODE (type) != REFERENCE_TYPE) - result = rvalue (result); - return result; - } - - /* [expr.static.cast] - - The inverse of any standard conversion sequence (clause _conv_), - other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer - (_conv.array_), function-to-pointer (_conv.func_), and boolean - (_conv.bool_) conversions, can be performed explicitly using - static_cast subject to the restriction that the explicit - conversion does not cast away constness (_expr.const.cast_), and - the following additional rules for specific cases: */ - /* For reference, the conversions not excluded are: integral - promotions, floating point promotion, integral conversions, - floating point conversions, floating-integral conversions, - pointer conversions, and pointer to member conversions. */ - /* DR 128 - - A value of integral _or enumeration_ type can be explicitly - converted to an enumeration type. */ - /* The effect of all that is that any conversion between any two - types which are integral, floating, or enumeration types can be - performed. */ - if ((INTEGRAL_OR_ENUMERATION_TYPE_P (type) - || SCALAR_FLOAT_TYPE_P (type)) - && (INTEGRAL_OR_ENUMERATION_TYPE_P (intype) - || SCALAR_FLOAT_TYPE_P (intype))) - return ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL, complain); - - if (TYPE_PTR_P (type) && TYPE_PTR_P (intype) - && CLASS_TYPE_P (TREE_TYPE (type)) - && CLASS_TYPE_P (TREE_TYPE (intype)) - && can_convert (build_pointer_type (TYPE_MAIN_VARIANT - (TREE_TYPE (intype))), - build_pointer_type (TYPE_MAIN_VARIANT - (TREE_TYPE (type))), - complain)) - { - tree base; - - if (!c_cast_p - && check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR, - complain)) - return error_mark_node; - base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype), - c_cast_p ? ba_unique : ba_check, - NULL, complain); - expr = build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false, - complain); - return cp_fold_convert(type, expr); - } - - if ((TYPE_PTRDATAMEM_P (type) && TYPE_PTRDATAMEM_P (intype)) - || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype))) - { - tree c1; - tree c2; - tree t1; - tree t2; - - c1 = TYPE_PTRMEM_CLASS_TYPE (intype); - c2 = TYPE_PTRMEM_CLASS_TYPE (type); - - if (TYPE_PTRDATAMEM_P (type)) - { - t1 = (build_ptrmem_type - (c1, - TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype)))); - t2 = (build_ptrmem_type - (c2, - TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type)))); - } - else - { - t1 = intype; - t2 = type; - } - if (can_convert (t1, t2, complain) || can_convert (t2, t1, complain)) - { - if (!c_cast_p - && check_for_casting_away_constness (intype, type, - STATIC_CAST_EXPR, - complain)) - return error_mark_node; - return convert_ptrmem (type, expr, /*allow_inverse_p=*/1, - c_cast_p, complain); - } - } - - /* [expr.static.cast] - - An rvalue of type "pointer to cv void" can be explicitly - converted to a pointer to object type. A value of type pointer - to object converted to "pointer to cv void" and back to the - original pointer type will have its original value. */ - if (TREE_CODE (intype) == POINTER_TYPE - && VOID_TYPE_P (TREE_TYPE (intype)) - && TYPE_PTROB_P (type)) - { - if (!c_cast_p - && check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR, - complain)) - return error_mark_node; - return build_nop (type, expr); - } - - *valid_p = false; - return error_mark_node; -} - -/* Return an expression representing static_cast<TYPE>(EXPR). */ - -tree -build_static_cast (tree type, tree expr, tsubst_flags_t complain) -{ - tree result; - bool valid_p; - - if (type == error_mark_node || expr == error_mark_node) - return error_mark_node; - - if (processing_template_decl) - { - expr = build_min (STATIC_CAST_EXPR, type, expr); - /* We don't know if it will or will not have side effects. */ - TREE_SIDE_EFFECTS (expr) = 1; - return convert_from_reference (expr); - } - - /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue. - Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */ - if (TREE_CODE (type) != REFERENCE_TYPE - && TREE_CODE (expr) == NOP_EXPR - && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0))) - expr = TREE_OPERAND (expr, 0); - - result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p, - complain); - if (valid_p) - { - if (result != error_mark_node) - maybe_warn_about_useless_cast (type, expr, complain); - return result; - } - - if (complain & tf_error) - error ("invalid static_cast from type %qT to type %qT", - TREE_TYPE (expr), type); - return error_mark_node; -} - -/* EXPR is an expression with member function or pointer-to-member - function type. TYPE is a pointer type. Converting EXPR to TYPE is - not permitted by ISO C++, but we accept it in some modes. If we - are not in one of those modes, issue a diagnostic. Return the - converted expression. */ - -tree -convert_member_func_to_ptr (tree type, tree expr, tsubst_flags_t complain) -{ - tree intype; - tree decl; - - intype = TREE_TYPE (expr); - gcc_assert (TYPE_PTRMEMFUNC_P (intype) - || TREE_CODE (intype) == METHOD_TYPE); - - if (!(complain & tf_warning_or_error)) - return error_mark_node; - - if (pedantic || warn_pmf2ptr) - pedwarn (input_location, pedantic ? OPT_Wpedantic : OPT_Wpmf_conversions, - "converting from %qT to %qT", intype, type); - - if (TREE_CODE (intype) == METHOD_TYPE) - expr = build_addr_func (expr, complain); - else if (TREE_CODE (expr) == PTRMEM_CST) - expr = build_address (PTRMEM_CST_MEMBER (expr)); - else - { - decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0); - decl = build_address (decl); - expr = get_member_function_from_ptrfunc (&decl, expr, complain); - } - - if (expr == error_mark_node) - return error_mark_node; - - return build_nop (type, expr); -} - -/* Return a representation for a reinterpret_cast from EXPR to TYPE. - If C_CAST_P is true, this reinterpret cast is being done as part of - a C-style cast. If VALID_P is non-NULL, *VALID_P is set to - indicate whether or not reinterpret_cast was valid. */ - -static tree -build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p, - bool *valid_p, tsubst_flags_t complain) -{ - tree intype; - - /* Assume the cast is invalid. */ - if (valid_p) - *valid_p = true; - - if (type == error_mark_node || error_operand_p (expr)) - return error_mark_node; - - intype = TREE_TYPE (expr); - - /* Save casted types in the function's used types hash table. */ - used_types_insert (type); - - /* [expr.reinterpret.cast] - An lvalue expression of type T1 can be cast to the type - "reference to T2" if an expression of type "pointer to T1" can be - explicitly converted to the type "pointer to T2" using a - reinterpret_cast. */ - if (TREE_CODE (type) == REFERENCE_TYPE) - { - if (! real_lvalue_p (expr)) - { - if (complain & tf_error) - error ("invalid cast of an rvalue expression of type " - "%qT to type %qT", - intype, type); - return error_mark_node; - } - - /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and - "B" are related class types; the reinterpret_cast does not - adjust the pointer. */ - if (TYPE_PTR_P (intype) - && (complain & tf_warning) - && (comptypes (TREE_TYPE (intype), TREE_TYPE (type), - COMPARE_BASE | COMPARE_DERIVED))) - warning (0, "casting %qT to %qT does not dereference pointer", - intype, type); - - expr = cp_build_addr_expr (expr, complain); - - if (warn_strict_aliasing > 2) - strict_aliasing_warning (TREE_TYPE (expr), type, expr); - - if (expr != error_mark_node) - expr = build_reinterpret_cast_1 - (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p, - valid_p, complain); - if (expr != error_mark_node) - /* cp_build_indirect_ref isn't right for rvalue refs. */ - expr = convert_from_reference (fold_convert (type, expr)); - return expr; - } - - /* As a G++ extension, we consider conversions from member - functions, and pointers to member functions to - pointer-to-function and pointer-to-void types. If - -Wno-pmf-conversions has not been specified, - convert_member_func_to_ptr will issue an error message. */ - if ((TYPE_PTRMEMFUNC_P (intype) - || TREE_CODE (intype) == METHOD_TYPE) - && TYPE_PTR_P (type) - && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE - || VOID_TYPE_P (TREE_TYPE (type)))) - return convert_member_func_to_ptr (type, expr, complain); - - /* If the cast is not to a reference type, the lvalue-to-rvalue, - array-to-pointer, and function-to-pointer conversions are - performed. */ - expr = decay_conversion (expr, complain); - - /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue. - Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */ - if (TREE_CODE (expr) == NOP_EXPR - && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0))) - expr = TREE_OPERAND (expr, 0); - - if (error_operand_p (expr)) - return error_mark_node; - - intype = TREE_TYPE (expr); - - /* [expr.reinterpret.cast] - A pointer can be converted to any integral type large enough to - hold it. ... A value of type std::nullptr_t can be converted to - an integral type; the conversion has the same meaning and - validity as a conversion of (void*)0 to the integral type. */ - if (CP_INTEGRAL_TYPE_P (type) - && (TYPE_PTR_P (intype) || NULLPTR_TYPE_P (intype))) - { - if (TYPE_PRECISION (type) < TYPE_PRECISION (intype)) - { - if (complain & tf_error) - permerror (input_location, "cast from %qT to %qT loses precision", - intype, type); - else - return error_mark_node; - } - if (NULLPTR_TYPE_P (intype)) - return build_int_cst (type, 0); - } - /* [expr.reinterpret.cast] - A value of integral or enumeration type can be explicitly - converted to a pointer. */ - else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype)) - /* OK */ - ; - else if ((INTEGRAL_OR_ENUMERATION_TYPE_P (type) - || TYPE_PTR_OR_PTRMEM_P (type)) - && same_type_p (type, intype)) - /* DR 799 */ - return fold_if_not_in_template (build_nop (type, expr)); - else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype)) - || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype))) - return fold_if_not_in_template (build_nop (type, expr)); - else if ((TYPE_PTRDATAMEM_P (type) && TYPE_PTRDATAMEM_P (intype)) - || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype))) - { - tree sexpr = expr; - - if (!c_cast_p - && check_for_casting_away_constness (intype, type, - REINTERPRET_CAST_EXPR, - complain)) - return error_mark_node; - /* Warn about possible alignment problems. */ - if (STRICT_ALIGNMENT && warn_cast_align - && (complain & tf_warning) - && !VOID_TYPE_P (type) - && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE - && COMPLETE_TYPE_P (TREE_TYPE (type)) - && COMPLETE_TYPE_P (TREE_TYPE (intype)) - && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype))) - warning (OPT_Wcast_align, "cast from %qT to %qT " - "increases required alignment of target type", intype, type); - - /* We need to strip nops here, because the front end likes to - create (int *)&a for array-to-pointer decay, instead of &a[0]. */ - STRIP_NOPS (sexpr); - if (warn_strict_aliasing <= 2) - strict_aliasing_warning (intype, type, sexpr); - - return fold_if_not_in_template (build_nop (type, expr)); - } - else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype)) - || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type))) - { - if (pedantic && (complain & tf_warning)) - /* Only issue a warning, as we have always supported this - where possible, and it is necessary in some cases. DR 195 - addresses this issue, but as of 2004/10/26 is still in - drafting. */ - warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object"); - return fold_if_not_in_template (build_nop (type, expr)); - } - else if (TREE_CODE (type) == VECTOR_TYPE) - return fold_if_not_in_template (convert_to_vector (type, expr)); - else if (TREE_CODE (intype) == VECTOR_TYPE - && INTEGRAL_OR_ENUMERATION_TYPE_P (type)) - return fold_if_not_in_template (convert_to_integer (type, expr)); - else - { - if (valid_p) - *valid_p = false; - if (complain & tf_error) - error ("invalid cast from type %qT to type %qT", intype, type); - return error_mark_node; - } - - return cp_convert (type, expr, complain); -} - -tree -build_reinterpret_cast (tree type, tree expr, tsubst_flags_t complain) -{ - tree r; - - if (type == error_mark_node || expr == error_mark_node) - return error_mark_node; - - if (processing_template_decl) - { - tree t = build_min (REINTERPRET_CAST_EXPR, type, expr); - - if (!TREE_SIDE_EFFECTS (t) - && type_dependent_expression_p (expr)) - /* There might turn out to be side effects inside expr. */ - TREE_SIDE_EFFECTS (t) = 1; - return convert_from_reference (t); - } - - r = build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false, - /*valid_p=*/NULL, complain); - if (r != error_mark_node) - maybe_warn_about_useless_cast (type, expr, complain); - return r; -} - -/* Perform a const_cast from EXPR to TYPE. If the cast is valid, - return an appropriate expression. Otherwise, return - error_mark_node. If the cast is not valid, and COMPLAIN is true, - then a diagnostic will be issued. If VALID_P is non-NULL, we are - performing a C-style cast, its value upon return will indicate - whether or not the conversion succeeded. */ - -static tree -build_const_cast_1 (tree dst_type, tree expr, tsubst_flags_t complain, - bool *valid_p) -{ - tree src_type; - tree reference_type; - - /* Callers are responsible for handling error_mark_node as a - destination type. */ - gcc_assert (dst_type != error_mark_node); - /* In a template, callers should be building syntactic - representations of casts, not using this machinery. */ - gcc_assert (!processing_template_decl); - - /* Assume the conversion is invalid. */ - if (valid_p) - *valid_p = false; - - if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRDATAMEM_P (dst_type)) - { - if (complain & tf_error) - error ("invalid use of const_cast with type %qT, " - "which is not a pointer, " - "reference, nor a pointer-to-data-member type", dst_type); - return error_mark_node; - } - - if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE) - { - if (complain & tf_error) - error ("invalid use of const_cast with type %qT, which is a pointer " - "or reference to a function type", dst_type); - return error_mark_node; - } - - /* Save casted types in the function's used types hash table. */ - used_types_insert (dst_type); - - src_type = TREE_TYPE (expr); - /* Expressions do not really have reference types. */ - if (TREE_CODE (src_type) == REFERENCE_TYPE) - src_type = TREE_TYPE (src_type); - - /* [expr.const.cast] - - For two object types T1 and T2, if a pointer to T1 can be explicitly - converted to the type "pointer to T2" using a const_cast, then the - following conversions can also be made: - - -- an lvalue of type T1 can be explicitly converted to an lvalue of - type T2 using the cast const_cast<T2&>; - - -- a glvalue of type T1 can be explicitly converted to an xvalue of - type T2 using the cast const_cast<T2&&>; and - - -- if T1 is a class type, a prvalue of type T1 can be explicitly - converted to an xvalue of type T2 using the cast const_cast<T2&&>. */ - - if (TREE_CODE (dst_type) == REFERENCE_TYPE) - { - reference_type = dst_type; - if (!TYPE_REF_IS_RVALUE (dst_type) - ? real_lvalue_p (expr) - : (CLASS_TYPE_P (TREE_TYPE (dst_type)) - ? lvalue_p (expr) - : lvalue_or_rvalue_with_address_p (expr))) - /* OK. */; - else - { - if (complain & tf_error) - error ("invalid const_cast of an rvalue of type %qT to type %qT", - src_type, dst_type); - return error_mark_node; - } - dst_type = build_pointer_type (TREE_TYPE (dst_type)); - src_type = build_pointer_type (src_type); - } - else - { - reference_type = NULL_TREE; - /* If the destination type is not a reference type, the - lvalue-to-rvalue, array-to-pointer, and function-to-pointer - conversions are performed. */ - src_type = type_decays_to (src_type); - if (src_type == error_mark_node) - return error_mark_node; - } - - if (TYPE_PTR_P (src_type) || TYPE_PTRDATAMEM_P (src_type)) - { - if (comp_ptr_ttypes_const (dst_type, src_type)) - { - if (valid_p) - { - *valid_p = true; - /* This cast is actually a C-style cast. Issue a warning if - the user is making a potentially unsafe cast. */ - check_for_casting_away_constness (src_type, dst_type, - CAST_EXPR, complain); - } - if (reference_type) - { - expr = cp_build_addr_expr (expr, complain); - if (expr == error_mark_node) - return error_mark_node; - expr = build_nop (reference_type, expr); - return convert_from_reference (expr); - } - else - { - expr = decay_conversion (expr, complain); - if (expr == error_mark_node) - return error_mark_node; - - /* build_c_cast puts on a NOP_EXPR to make the result not an - lvalue. Strip such NOP_EXPRs if VALUE is being used in - non-lvalue context. */ - if (TREE_CODE (expr) == NOP_EXPR - && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0))) - expr = TREE_OPERAND (expr, 0); - return build_nop (dst_type, expr); - } - } - else if (valid_p - && !at_least_as_qualified_p (TREE_TYPE (dst_type), - TREE_TYPE (src_type))) - check_for_casting_away_constness (src_type, dst_type, CAST_EXPR, - complain); - } - - if (complain & tf_error) - error ("invalid const_cast from type %qT to type %qT", - src_type, dst_type); - return error_mark_node; -} - -tree -build_const_cast (tree type, tree expr, tsubst_flags_t complain) -{ - tree r; - - if (type == error_mark_node || error_operand_p (expr)) - return error_mark_node; - - if (processing_template_decl) - { - tree t = build_min (CONST_CAST_EXPR, type, expr); - - if (!TREE_SIDE_EFFECTS (t) - && type_dependent_expression_p (expr)) - /* There might turn out to be side effects inside expr. */ - TREE_SIDE_EFFECTS (t) = 1; - return convert_from_reference (t); - } - - r = build_const_cast_1 (type, expr, complain, /*valid_p=*/NULL); - if (r != error_mark_node) - maybe_warn_about_useless_cast (type, expr, complain); - return r; -} - -/* Like cp_build_c_cast, but for the c-common bits. */ - -tree -build_c_cast (location_t /*loc*/, tree type, tree expr) -{ - return cp_build_c_cast (type, expr, tf_warning_or_error); -} - -/* Build an expression representing an explicit C-style cast to type - TYPE of expression EXPR. */ - -tree -cp_build_c_cast (tree type, tree expr, tsubst_flags_t complain) -{ - tree value = expr; - tree result; - bool valid_p; - - if (type == error_mark_node || error_operand_p (expr)) - return error_mark_node; - - if (processing_template_decl) - { - tree t = build_min (CAST_EXPR, type, - tree_cons (NULL_TREE, value, NULL_TREE)); - /* We don't know if it will or will not have side effects. */ - TREE_SIDE_EFFECTS (t) = 1; - return convert_from_reference (t); - } - - /* Casts to a (pointer to a) specific ObjC class (or 'id' or - 'Class') should always be retained, because this information aids - in method lookup. */ - if (objc_is_object_ptr (type) - && objc_is_object_ptr (TREE_TYPE (expr))) - return build_nop (type, expr); - - /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue. - Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */ - if (TREE_CODE (type) != REFERENCE_TYPE - && TREE_CODE (value) == NOP_EXPR - && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0))) - value = TREE_OPERAND (value, 0); - - if (TREE_CODE (type) == ARRAY_TYPE) - { - /* Allow casting from T1* to T2[] because Cfront allows it. - NIHCL uses it. It is not valid ISO C++ however. */ - if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE) - { - if (complain & tf_error) - permerror (input_location, "ISO C++ forbids casting to an array type %qT", type); - else - return error_mark_node; - type = build_pointer_type (TREE_TYPE (type)); - } - else - { - if (complain & tf_error) - error ("ISO C++ forbids casting to an array type %qT", type); - return error_mark_node; - } - } - - if (TREE_CODE (type) == FUNCTION_TYPE - || TREE_CODE (type) == METHOD_TYPE) - { - if (complain & tf_error) - error ("invalid cast to function type %qT", type); - return error_mark_node; - } - - if (TREE_CODE (type) == POINTER_TYPE - && TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE - /* Casting to an integer of smaller size is an error detected elsewhere. */ - && TYPE_PRECISION (type) > TYPE_PRECISION (TREE_TYPE (value)) - /* Don't warn about converting any constant. */ - && !TREE_CONSTANT (value)) - warning_at (input_location, OPT_Wint_to_pointer_cast, - "cast to pointer from integer of different size"); - - /* A C-style cast can be a const_cast. */ - result = build_const_cast_1 (type, value, complain & tf_warning, - &valid_p); - if (valid_p) - { - if (result != error_mark_node) - maybe_warn_about_useless_cast (type, value, complain); - return result; - } - - /* Or a static cast. */ - result = build_static_cast_1 (type, value, /*c_cast_p=*/true, - &valid_p, complain); - /* Or a reinterpret_cast. */ - if (!valid_p) - result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true, - &valid_p, complain); - /* The static_cast or reinterpret_cast may be followed by a - const_cast. */ - if (valid_p - /* A valid cast may result in errors if, for example, a - conversion to an ambiguous base class is required. */ - && !error_operand_p (result)) - { - tree result_type; - - maybe_warn_about_useless_cast (type, value, complain); - - /* Non-class rvalues always have cv-unqualified type. */ - if (!CLASS_TYPE_P (type)) - type = TYPE_MAIN_VARIANT (type); - result_type = TREE_TYPE (result); - if (!CLASS_TYPE_P (result_type) && TREE_CODE (type) != REFERENCE_TYPE) - result_type = TYPE_MAIN_VARIANT (result_type); - /* If the type of RESULT does not match TYPE, perform a - const_cast to make it match. If the static_cast or - reinterpret_cast succeeded, we will differ by at most - cv-qualification, so the follow-on const_cast is guaranteed - to succeed. */ - if (!same_type_p (non_reference (type), non_reference (result_type))) - { - result = build_const_cast_1 (type, result, false, &valid_p); - gcc_assert (valid_p); - } - return result; - } - - return error_mark_node; -} - -/* For use from the C common bits. */ -tree -build_modify_expr (location_t /*location*/, - tree lhs, tree /*lhs_origtype*/, - enum tree_code modifycode, - location_t /*rhs_location*/, tree rhs, - tree /*rhs_origtype*/) -{ - return cp_build_modify_expr (lhs, modifycode, rhs, tf_warning_or_error); -} - -/* Build an assignment expression of lvalue LHS from value RHS. - MODIFYCODE is the code for a binary operator that we use - to combine the old value of LHS with RHS to get the new value. - Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. - - C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */ - -tree -cp_build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs, - tsubst_flags_t complain) -{ - tree result; - tree newrhs = rhs; - tree lhstype = TREE_TYPE (lhs); - tree olhstype = lhstype; - bool plain_assign = (modifycode == NOP_EXPR); - - /* Avoid duplicate error messages from operands that had errors. */ - if (error_operand_p (lhs) || error_operand_p (rhs)) - return error_mark_node; - - /* Handle control structure constructs used as "lvalues". */ - switch (TREE_CODE (lhs)) - { - /* Handle --foo = 5; as these are valid constructs in C++. */ - case PREDECREMENT_EXPR: - case PREINCREMENT_EXPR: - if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))) - lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs), - stabilize_reference (TREE_OPERAND (lhs, 0)), - TREE_OPERAND (lhs, 1)); - newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0), - modifycode, rhs, complain); - if (newrhs == error_mark_node) - return error_mark_node; - return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs); - - /* Handle (a, b) used as an "lvalue". */ - case COMPOUND_EXPR: - newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 1), - modifycode, rhs, complain); - if (newrhs == error_mark_node) - return error_mark_node; - return build2 (COMPOUND_EXPR, lhstype, - TREE_OPERAND (lhs, 0), newrhs); - - case MODIFY_EXPR: - if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))) - lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs), - stabilize_reference (TREE_OPERAND (lhs, 0)), - TREE_OPERAND (lhs, 1)); - newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs, - complain); - if (newrhs == error_mark_node) - return error_mark_node; - return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs); - - case MIN_EXPR: - case MAX_EXPR: - /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues, - when neither operand has side-effects. */ - if (!lvalue_or_else (lhs, lv_assign, complain)) - return error_mark_node; - - gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)) - && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1))); - - lhs = build3 (COND_EXPR, TREE_TYPE (lhs), - build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR, - boolean_type_node, - TREE_OPERAND (lhs, 0), - TREE_OPERAND (lhs, 1)), - TREE_OPERAND (lhs, 0), - TREE_OPERAND (lhs, 1)); - /* Fall through. */ - - /* Handle (a ? b : c) used as an "lvalue". */ - case COND_EXPR: - { - /* Produce (a ? (b = rhs) : (c = rhs)) - except that the RHS goes through a save-expr - so the code to compute it is only emitted once. */ - tree cond; - tree preeval = NULL_TREE; - - if (VOID_TYPE_P (TREE_TYPE (rhs))) - { - if (complain & tf_error) - error ("void value not ignored as it ought to be"); - return error_mark_node; - } - - rhs = stabilize_expr (rhs, &preeval); - - /* Check this here to avoid odd errors when trying to convert - a throw to the type of the COND_EXPR. */ - if (!lvalue_or_else (lhs, lv_assign, complain)) - return error_mark_node; - - cond = build_conditional_expr - (TREE_OPERAND (lhs, 0), - cp_build_modify_expr (TREE_OPERAND (lhs, 1), - modifycode, rhs, complain), - cp_build_modify_expr (TREE_OPERAND (lhs, 2), - modifycode, rhs, complain), - complain); - - if (cond == error_mark_node) - return cond; - /* Make sure the code to compute the rhs comes out - before the split. */ - if (preeval) - cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond); - return cond; - } - - default: - break; - } - - if (modifycode == INIT_EXPR) - { - if (BRACE_ENCLOSED_INITIALIZER_P (rhs)) - /* Do the default thing. */; - else if (TREE_CODE (rhs) == CONSTRUCTOR) - { - /* Compound literal. */ - if (! same_type_p (TREE_TYPE (rhs), lhstype)) - /* Call convert to generate an error; see PR 11063. */ - rhs = convert (lhstype, rhs); - result = build2 (INIT_EXPR, lhstype, lhs, rhs); - TREE_SIDE_EFFECTS (result) = 1; - return result; - } - else if (! MAYBE_CLASS_TYPE_P (lhstype)) - /* Do the default thing. */; - else - { - vec<tree, va_gc> *rhs_vec = make_tree_vector_single (rhs); - result = build_special_member_call (lhs, complete_ctor_identifier, - &rhs_vec, lhstype, LOOKUP_NORMAL, - complain); - release_tree_vector (rhs_vec); - if (result == NULL_TREE) - return error_mark_node; - return result; - } - } - else - { - lhs = require_complete_type_sfinae (lhs, complain); - if (lhs == error_mark_node) - return error_mark_node; - - if (modifycode == NOP_EXPR) - { - if (c_dialect_objc ()) - { - result = objc_maybe_build_modify_expr (lhs, rhs); - if (result) - return result; - } - - /* `operator=' is not an inheritable operator. */ - if (! MAYBE_CLASS_TYPE_P (lhstype)) - /* Do the default thing. */; - else - { - result = build_new_op (input_location, MODIFY_EXPR, - LOOKUP_NORMAL, lhs, rhs, - make_node (NOP_EXPR), /*overload=*/NULL, - complain); - if (result == NULL_TREE) - return error_mark_node; - return result; - } - lhstype = olhstype; - } - else - { - tree init = NULL_TREE; - - /* A binary op has been requested. Combine the old LHS - value with the RHS producing the value we should actually - store into the LHS. */ - gcc_assert (!((TREE_CODE (lhstype) == REFERENCE_TYPE - && MAYBE_CLASS_TYPE_P (TREE_TYPE (lhstype))) - || MAYBE_CLASS_TYPE_P (lhstype))); - - /* Preevaluate the RHS to make sure its evaluation is complete - before the lvalue-to-rvalue conversion of the LHS: - - [expr.ass] With respect to an indeterminately-sequenced - function call, the operation of a compound assignment is a - single evaluation. [ Note: Therefore, a function call shall - not intervene between the lvalue-to-rvalue conversion and the - side effect associated with any single compound assignment - operator. -- end note ] */ - lhs = stabilize_reference (lhs); - if (TREE_SIDE_EFFECTS (rhs)) - rhs = mark_rvalue_use (rhs); - rhs = stabilize_expr (rhs, &init); - newrhs = cp_build_binary_op (input_location, - modifycode, lhs, rhs, - complain); - if (newrhs == error_mark_node) - { - if (complain & tf_error) - error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode, - TREE_TYPE (lhs), TREE_TYPE (rhs)); - return error_mark_node; - } - - if (init) - newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), init, newrhs); - - /* Now it looks like a plain assignment. */ - modifycode = NOP_EXPR; - if (c_dialect_objc ()) - { - result = objc_maybe_build_modify_expr (lhs, newrhs); - if (result) - return result; - } - } - gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE); - gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE); - } - - /* The left-hand side must be an lvalue. */ - if (!lvalue_or_else (lhs, lv_assign, complain)) - return error_mark_node; - - /* Warn about modifying something that is `const'. Don't warn if - this is initialization. */ - if (modifycode != INIT_EXPR - && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype) - /* Functions are not modifiable, even though they are - lvalues. */ - || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE - || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE - /* If it's an aggregate and any field is const, then it is - effectively const. */ - || (CLASS_TYPE_P (lhstype) - && C_TYPE_FIELDS_READONLY (lhstype)))) - { - if (complain & tf_error) - cxx_readonly_error (lhs, lv_assign); - else - return error_mark_node; - } - - /* If storing into a structure or union member, it may have been given a - lowered bitfield type. We need to convert to the declared type first, - so retrieve it now. */ - - olhstype = unlowered_expr_type (lhs); - - /* Convert new value to destination type. */ - - if (TREE_CODE (lhstype) == ARRAY_TYPE) - { - int from_array; - - if (BRACE_ENCLOSED_INITIALIZER_P (newrhs)) - { - if (modifycode != INIT_EXPR) - { - if (complain & tf_error) - error ("assigning to an array from an initializer list"); - return error_mark_node; - } - if (check_array_initializer (lhs, lhstype, newrhs)) - return error_mark_node; - newrhs = digest_init (lhstype, newrhs, complain); - if (newrhs == error_mark_node) - return error_mark_node; - } - - else if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype), - TYPE_MAIN_VARIANT (TREE_TYPE (newrhs)))) - { - if (complain & tf_error) - error ("incompatible types in assignment of %qT to %qT", - TREE_TYPE (rhs), lhstype); - return error_mark_node; - } - - /* Allow array assignment in compiler-generated code. */ - else if (!current_function_decl - || !DECL_DEFAULTED_FN (current_function_decl)) - { - /* This routine is used for both initialization and assignment. - Make sure the diagnostic message differentiates the context. */ - if (complain & tf_error) - { - if (modifycode == INIT_EXPR) - error ("array used as initializer"); - else - error ("invalid array assignment"); - } - return error_mark_node; - } - - from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE - ? 1 + (modifycode != INIT_EXPR): 0; - return build_vec_init (lhs, NULL_TREE, newrhs, - /*explicit_value_init_p=*/false, - from_array, complain); - } - - if (modifycode == INIT_EXPR) - /* Calls with INIT_EXPR are all direct-initialization, so don't set - LOOKUP_ONLYCONVERTING. */ - newrhs = convert_for_initialization (lhs, olhstype, newrhs, LOOKUP_NORMAL, - ICR_INIT, NULL_TREE, 0, - complain); - else - newrhs = convert_for_assignment (olhstype, newrhs, ICR_ASSIGN, - NULL_TREE, 0, complain, LOOKUP_IMPLICIT); - - if (!same_type_p (lhstype, olhstype)) - newrhs = cp_convert_and_check (lhstype, newrhs, complain); - - if (modifycode != INIT_EXPR) - { - if (TREE_CODE (newrhs) == CALL_EXPR - && TYPE_NEEDS_CONSTRUCTING (lhstype)) - newrhs = build_cplus_new (lhstype, newrhs, complain); - - /* Can't initialize directly from a TARGET_EXPR, since that would - cause the lhs to be constructed twice, and possibly result in - accidental self-initialization. So we force the TARGET_EXPR to be - expanded without a target. */ - if (TREE_CODE (newrhs) == TARGET_EXPR) - newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs, - TREE_OPERAND (newrhs, 0)); - } - - if (newrhs == error_mark_node) - return error_mark_node; - - if (c_dialect_objc () && flag_objc_gc) - { - result = objc_generate_write_barrier (lhs, modifycode, newrhs); - - if (result) - return result; - } - - result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR, - lhstype, lhs, newrhs); - - TREE_SIDE_EFFECTS (result) = 1; - if (!plain_assign) - TREE_NO_WARNING (result) = 1; - - return result; -} - -tree -build_x_modify_expr (location_t loc, tree lhs, enum tree_code modifycode, - tree rhs, tsubst_flags_t complain) -{ - if (processing_template_decl) - return build_min_nt_loc (loc, MODOP_EXPR, lhs, - build_min_nt_loc (loc, modifycode, NULL_TREE, - NULL_TREE), rhs); - - if (modifycode != NOP_EXPR) - { - tree rval = build_new_op (loc, MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs, - make_node (modifycode), /*overload=*/NULL, - complain); - if (rval) - { - TREE_NO_WARNING (rval) = 1; - return rval; - } - } - return cp_build_modify_expr (lhs, modifycode, rhs, complain); -} - -/* Helper function for get_delta_difference which assumes FROM is a base - class of TO. Returns a delta for the conversion of pointer-to-member - of FROM to pointer-to-member of TO. If the conversion is invalid and - tf_error is not set in COMPLAIN returns error_mark_node, otherwise - returns zero. If FROM is not a base class of TO, returns NULL_TREE. - If C_CAST_P is true, this conversion is taking place as part of a - C-style cast. */ - -static tree -get_delta_difference_1 (tree from, tree to, bool c_cast_p, - tsubst_flags_t complain) -{ - tree binfo; - base_kind kind; - - binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, - &kind, complain); - - if (binfo == error_mark_node) - { - if (!(complain & tf_error)) - return error_mark_node; - - error (" in pointer to member function conversion"); - return size_zero_node; - } - else if (binfo) - { - if (kind != bk_via_virtual) - return BINFO_OFFSET (binfo); - else - /* FROM is a virtual base class of TO. Issue an error or warning - depending on whether or not this is a reinterpret cast. */ - { - if (!(complain & tf_error)) - return error_mark_node; - - error ("pointer to member conversion via virtual base %qT", - BINFO_TYPE (binfo_from_vbase (binfo))); - - return size_zero_node; - } - } - else - return NULL_TREE; -} - -/* Get difference in deltas for different pointer to member function - types. If the conversion is invalid and tf_error is not set in - COMPLAIN, returns error_mark_node, otherwise returns an integer - constant of type PTRDIFF_TYPE_NODE and its value is zero if the - conversion is invalid. If ALLOW_INVERSE_P is true, then allow reverse - conversions as well. If C_CAST_P is true this conversion is taking - place as part of a C-style cast. - - Note that the naming of FROM and TO is kind of backwards; the return - value is what we add to a TO in order to get a FROM. They are named - this way because we call this function to find out how to convert from - a pointer to member of FROM to a pointer to member of TO. */ - -static tree -get_delta_difference (tree from, tree to, - bool allow_inverse_p, - bool c_cast_p, tsubst_flags_t complain) -{ - tree result; - - if (same_type_ignoring_top_level_qualifiers_p (from, to)) - /* Pointer to member of incomplete class is permitted*/ - result = size_zero_node; - else - result = get_delta_difference_1 (from, to, c_cast_p, complain); - - if (result == error_mark_node) - return error_mark_node; - - if (!result) - { - if (!allow_inverse_p) - { - if (!(complain & tf_error)) - return error_mark_node; - - error_not_base_type (from, to); - error (" in pointer to member conversion"); - result = size_zero_node; - } - else - { - result = get_delta_difference_1 (to, from, c_cast_p, complain); - - if (result == error_mark_node) - return error_mark_node; - - if (result) - result = size_diffop_loc (input_location, - size_zero_node, result); - else - { - if (!(complain & tf_error)) - return error_mark_node; - - error_not_base_type (from, to); - error (" in pointer to member conversion"); - result = size_zero_node; - } - } - } - - return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node, - result)); -} - -/* Return a constructor for the pointer-to-member-function TYPE using - the other components as specified. */ - -tree -build_ptrmemfunc1 (tree type, tree delta, tree pfn) -{ - tree u = NULL_TREE; - tree delta_field; - tree pfn_field; - vec<constructor_elt, va_gc> *v; - - /* Pull the FIELD_DECLs out of the type. */ - pfn_field = TYPE_FIELDS (type); - delta_field = DECL_CHAIN (pfn_field); - - /* Make sure DELTA has the type we want. */ - delta = convert_and_check (delta_type_node, delta); - - /* Convert to the correct target type if necessary. */ - pfn = fold_convert (TREE_TYPE (pfn_field), pfn); - - /* Finish creating the initializer. */ - vec_alloc (v, 2); - CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn); - CONSTRUCTOR_APPEND_ELT(v, delta_field, delta); - u = build_constructor (type, v); - TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta); - TREE_STATIC (u) = (TREE_CONSTANT (u) - && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn)) - != NULL_TREE) - && (initializer_constant_valid_p (delta, TREE_TYPE (delta)) - != NULL_TREE)); - return u; -} - -/* Build a constructor for a pointer to member function. It can be - used to initialize global variables, local variable, or used - as a value in expressions. TYPE is the POINTER to METHOD_TYPE we - want to be. - - If FORCE is nonzero, then force this conversion, even if - we would rather not do it. Usually set when using an explicit - cast. A C-style cast is being processed iff C_CAST_P is true. - - Return error_mark_node, if something goes wrong. */ - -tree -build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p, - tsubst_flags_t complain) -{ - tree fn; - tree pfn_type; - tree to_type; - - if (error_operand_p (pfn)) - return error_mark_node; - - pfn_type = TREE_TYPE (pfn); - to_type = build_ptrmemfunc_type (type); - - /* Handle multiple conversions of pointer to member functions. */ - if (TYPE_PTRMEMFUNC_P (pfn_type)) - { - tree delta = NULL_TREE; - tree npfn = NULL_TREE; - tree n; - - if (!force - && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, - LOOKUP_NORMAL, complain)) - error ("invalid conversion to type %qT from type %qT", - to_type, pfn_type); - - n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type), - TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type), - force, - c_cast_p, complain); - if (n == error_mark_node) - return error_mark_node; - - /* We don't have to do any conversion to convert a - pointer-to-member to its own type. But, we don't want to - just return a PTRMEM_CST if there's an explicit cast; that - cast should make the expression an invalid template argument. */ - if (TREE_CODE (pfn) != PTRMEM_CST) - { - if (same_type_p (to_type, pfn_type)) - return pfn; - else if (integer_zerop (n)) - return build_reinterpret_cast (to_type, pfn, - complain); - } - - if (TREE_SIDE_EFFECTS (pfn)) - pfn = save_expr (pfn); - - /* Obtain the function pointer and the current DELTA. */ - if (TREE_CODE (pfn) == PTRMEM_CST) - expand_ptrmemfunc_cst (pfn, &delta, &npfn); - else - { - npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier); - delta = build_ptrmemfunc_access_expr (pfn, delta_identifier); - } - - /* Just adjust the DELTA field. */ - gcc_assert (same_type_ignoring_top_level_qualifiers_p - (TREE_TYPE (delta), ptrdiff_type_node)); - if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta) - n = cp_build_binary_op (input_location, - LSHIFT_EXPR, n, integer_one_node, - complain); - delta = cp_build_binary_op (input_location, - PLUS_EXPR, delta, n, complain); - return build_ptrmemfunc1 (to_type, delta, npfn); - } - - /* Handle null pointer to member function conversions. */ - if (null_ptr_cst_p (pfn)) - { - pfn = build_c_cast (input_location, type, pfn); - return build_ptrmemfunc1 (to_type, - integer_zero_node, - pfn); - } - - if (type_unknown_p (pfn)) - return instantiate_type (type, pfn, complain); - - fn = TREE_OPERAND (pfn, 0); - gcc_assert (TREE_CODE (fn) == FUNCTION_DECL - /* In a template, we will have preserved the - OFFSET_REF. */ - || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF)); - return make_ptrmem_cst (to_type, fn); -} - -/* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST - given by CST. - - ??? There is no consistency as to the types returned for the above - values. Some code acts as if it were a sizetype and some as if it were - integer_type_node. */ - -void -expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn) -{ - tree type = TREE_TYPE (cst); - tree fn = PTRMEM_CST_MEMBER (cst); - tree ptr_class, fn_class; - - gcc_assert (TREE_CODE (fn) == FUNCTION_DECL); - - /* The class that the function belongs to. */ - fn_class = DECL_CONTEXT (fn); - - /* The class that we're creating a pointer to member of. */ - ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type); - - /* First, calculate the adjustment to the function's class. */ - *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0, - /*c_cast_p=*/0, tf_warning_or_error); - - if (!DECL_VIRTUAL_P (fn)) - *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), - build_addr_func (fn, tf_warning_or_error)); - else - { - /* If we're dealing with a virtual function, we have to adjust 'this' - again, to point to the base which provides the vtable entry for - fn; the call will do the opposite adjustment. */ - tree orig_class = DECL_CONTEXT (fn); - tree binfo = binfo_or_else (orig_class, fn_class); - *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta), - *delta, BINFO_OFFSET (binfo)); - *delta = fold_if_not_in_template (*delta); - - /* We set PFN to the vtable offset at which the function can be - found, plus one (unless ptrmemfunc_vbit_in_delta, in which - case delta is shifted left, and then incremented). */ - *pfn = DECL_VINDEX (fn); - *pfn = build2 (MULT_EXPR, integer_type_node, *pfn, - TYPE_SIZE_UNIT (vtable_entry_type)); - *pfn = fold_if_not_in_template (*pfn); - - switch (TARGET_PTRMEMFUNC_VBIT_LOCATION) - { - case ptrmemfunc_vbit_in_pfn: - *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn, - integer_one_node); - *pfn = fold_if_not_in_template (*pfn); - break; - - case ptrmemfunc_vbit_in_delta: - *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta), - *delta, integer_one_node); - *delta = fold_if_not_in_template (*delta); - *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta), - *delta, integer_one_node); - *delta = fold_if_not_in_template (*delta); - break; - - default: - gcc_unreachable (); - } - - *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn); - *pfn = fold_if_not_in_template (*pfn); - } -} - -/* Return an expression for PFN from the pointer-to-member function - given by T. */ - -static tree -pfn_from_ptrmemfunc (tree t) -{ - if (TREE_CODE (t) == PTRMEM_CST) - { - tree delta; - tree pfn; - - expand_ptrmemfunc_cst (t, &delta, &pfn); - if (pfn) - return pfn; - } - - return build_ptrmemfunc_access_expr (t, pfn_identifier); -} - -/* Return an expression for DELTA from the pointer-to-member function - given by T. */ - -static tree -delta_from_ptrmemfunc (tree t) -{ - if (TREE_CODE (t) == PTRMEM_CST) - { - tree delta; - tree pfn; - - expand_ptrmemfunc_cst (t, &delta, &pfn); - if (delta) - return delta; - } - - return build_ptrmemfunc_access_expr (t, delta_identifier); -} - -/* Convert value RHS to type TYPE as preparation for an assignment to - an lvalue of type TYPE. ERRTYPE indicates what kind of error the - implicit conversion is. If FNDECL is non-NULL, we are doing the - conversion in order to pass the PARMNUMth argument of FNDECL. - If FNDECL is NULL, we are doing the conversion in function pointer - argument passing, conversion in initialization, etc. */ - -static tree -convert_for_assignment (tree type, tree rhs, - impl_conv_rhs errtype, tree fndecl, int parmnum, - tsubst_flags_t complain, int flags) -{ - tree rhstype; - enum tree_code coder; - - /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ - if (TREE_CODE (rhs) == NON_LVALUE_EXPR) - rhs = TREE_OPERAND (rhs, 0); - - rhstype = TREE_TYPE (rhs); - coder = TREE_CODE (rhstype); - - if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE - && vector_types_convertible_p (type, rhstype, true)) - { - rhs = mark_rvalue_use (rhs); - return convert (type, rhs); - } - - if (rhs == error_mark_node || rhstype == error_mark_node) - return error_mark_node; - if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node) - return error_mark_node; - - /* The RHS of an assignment cannot have void type. */ - if (coder == VOID_TYPE) - { - if (complain & tf_error) - error ("void value not ignored as it ought to be"); - return error_mark_node; - } - - if (c_dialect_objc ()) - { - int parmno; - tree selector; - tree rname = fndecl; - - switch (errtype) - { - case ICR_ASSIGN: - parmno = -1; - break; - case ICR_INIT: - parmno = -2; - break; - default: - selector = objc_message_selector (); - parmno = parmnum; - if (selector && parmno > 1) - { - rname = selector; - parmno -= 1; - } - } - - if (objc_compare_types (type, rhstype, parmno, rname)) - { - rhs = mark_rvalue_use (rhs); - return convert (type, rhs); - } - } - - /* [expr.ass] - - The expression is implicitly converted (clause _conv_) to the - cv-unqualified type of the left operand. - - We allow bad conversions here because by the time we get to this point - we are committed to doing the conversion. If we end up doing a bad - conversion, convert_like will complain. */ - if (!can_convert_arg_bad (type, rhstype, rhs, flags, complain)) - { - /* When -Wno-pmf-conversions is use, we just silently allow - conversions from pointers-to-members to plain pointers. If - the conversion doesn't work, cp_convert will complain. */ - if (!warn_pmf2ptr - && TYPE_PTR_P (type) - && TYPE_PTRMEMFUNC_P (rhstype)) - rhs = cp_convert (strip_top_quals (type), rhs, complain); - else - { - if (complain & tf_error) - { - /* If the right-hand side has unknown type, then it is an - overloaded function. Call instantiate_type to get error - messages. */ - if (rhstype == unknown_type_node) - instantiate_type (type, rhs, tf_warning_or_error); - else if (fndecl) - error ("cannot convert %qT to %qT for argument %qP to %qD", - rhstype, type, parmnum, fndecl); - else - switch (errtype) - { - case ICR_DEFAULT_ARGUMENT: - error ("cannot convert %qT to %qT in default argument", - rhstype, type); - break; - case ICR_ARGPASS: - error ("cannot convert %qT to %qT in argument passing", - rhstype, type); - break; - case ICR_CONVERTING: - error ("cannot convert %qT to %qT", - rhstype, type); - break; - case ICR_INIT: - error ("cannot convert %qT to %qT in initialization", - rhstype, type); - break; - case ICR_RETURN: - error ("cannot convert %qT to %qT in return", - rhstype, type); - break; - case ICR_ASSIGN: - error ("cannot convert %qT to %qT in assignment", - rhstype, type); - break; - default: - gcc_unreachable(); - } - } - return error_mark_node; - } - } - if (warn_suggest_attribute_format) - { - const enum tree_code codel = TREE_CODE (type); - if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE) - && coder == codel - && check_missing_format_attribute (type, rhstype) - && (complain & tf_warning)) - switch (errtype) - { - case ICR_ARGPASS: - case ICR_DEFAULT_ARGUMENT: - if (fndecl) - warning (OPT_Wsuggest_attribute_format, - "parameter %qP of %qD might be a candidate " - "for a format attribute", parmnum, fndecl); - else - warning (OPT_Wsuggest_attribute_format, - "parameter might be a candidate " - "for a format attribute"); - break; - case ICR_CONVERTING: - warning (OPT_Wsuggest_attribute_format, - "target of conversion might be a candidate " - "for a format attribute"); - break; - case ICR_INIT: - warning (OPT_Wsuggest_attribute_format, - "target of initialization might be a candidate " - "for a format attribute"); - break; - case ICR_RETURN: - warning (OPT_Wsuggest_attribute_format, - "return type might be a candidate " - "for a format attribute"); - break; - case ICR_ASSIGN: - warning (OPT_Wsuggest_attribute_format, - "left-hand side of assignment might be a candidate " - "for a format attribute"); - break; - default: - gcc_unreachable(); - } - } - - /* If -Wparentheses, warn about a = b = c when a has type bool and b - does not. */ - if (warn_parentheses - && TREE_CODE (type) == BOOLEAN_TYPE - && TREE_CODE (rhs) == MODIFY_EXPR - && !TREE_NO_WARNING (rhs) - && TREE_CODE (TREE_TYPE (rhs)) != BOOLEAN_TYPE - && (complain & tf_warning)) - { - location_t loc = EXPR_LOC_OR_HERE (rhs); - - warning_at (loc, OPT_Wparentheses, - "suggest parentheses around assignment used as truth value"); - TREE_NO_WARNING (rhs) = 1; - } - - return perform_implicit_conversion_flags (strip_top_quals (type), rhs, - complain, flags); -} - -/* Convert RHS to be of type TYPE. - If EXP is nonzero, it is the target of the initialization. - ERRTYPE indicates what kind of error the implicit conversion is. - - Two major differences between the behavior of - `convert_for_assignment' and `convert_for_initialization' - are that references are bashed in the former, while - copied in the latter, and aggregates are assigned in - the former (operator=) while initialized in the - latter (X(X&)). - - If using constructor make sure no conversion operator exists, if one does - exist, an ambiguity exists. */ - -tree -convert_for_initialization (tree exp, tree type, tree rhs, int flags, - impl_conv_rhs errtype, tree fndecl, int parmnum, - tsubst_flags_t complain) -{ - enum tree_code codel = TREE_CODE (type); - tree rhstype; - enum tree_code coder; - - /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue. - Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */ - if (TREE_CODE (rhs) == NOP_EXPR - && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0)) - && codel != REFERENCE_TYPE) - rhs = TREE_OPERAND (rhs, 0); - - if (type == error_mark_node - || rhs == error_mark_node - || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)) - return error_mark_node; - - if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE - && TREE_CODE (type) != ARRAY_TYPE - && (TREE_CODE (type) != REFERENCE_TYPE - || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE)) - || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE - && (TREE_CODE (type) != REFERENCE_TYPE - || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)) - || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE) - rhs = decay_conversion (rhs, complain); - - rhstype = TREE_TYPE (rhs); - coder = TREE_CODE (rhstype); - - if (coder == ERROR_MARK) - return error_mark_node; - - /* We accept references to incomplete types, so we can - return here before checking if RHS is of complete type. */ - - if (codel == REFERENCE_TYPE) - { - /* This should eventually happen in convert_arguments. */ - int savew = 0, savee = 0; - - if (fndecl) - savew = warningcount, savee = errorcount; - rhs = initialize_reference (type, rhs, flags, complain); - if (fndecl) - { - if (warningcount > savew) - warning (0, "in passing argument %P of %q+D", parmnum, fndecl); - else if (errorcount > savee) - error ("in passing argument %P of %q+D", parmnum, fndecl); - } - return rhs; - } - - if (exp != 0) - exp = require_complete_type_sfinae (exp, complain); - if (exp == error_mark_node) - return error_mark_node; - - rhstype = non_reference (rhstype); - - type = complete_type (type); - - if (DIRECT_INIT_EXPR_P (type, rhs)) - /* Don't try to do copy-initialization if we already have - direct-initialization. */ - return rhs; - - if (MAYBE_CLASS_TYPE_P (type)) - return perform_implicit_conversion_flags (type, rhs, complain, flags); - - return convert_for_assignment (type, rhs, errtype, fndecl, parmnum, - complain, flags); -} - -/* If RETVAL is the address of, or a reference to, a local variable or - temporary give an appropriate warning. */ - -static void -maybe_warn_about_returning_address_of_local (tree retval) -{ - tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl)); - tree whats_returned = retval; - - for (;;) - { - if (TREE_CODE (whats_returned) == COMPOUND_EXPR) - whats_returned = TREE_OPERAND (whats_returned, 1); - else if (CONVERT_EXPR_P (whats_returned) - || TREE_CODE (whats_returned) == NON_LVALUE_EXPR) - whats_returned = TREE_OPERAND (whats_returned, 0); - else - break; - } - - if (TREE_CODE (whats_returned) != ADDR_EXPR) - return; - whats_returned = TREE_OPERAND (whats_returned, 0); - - if (TREE_CODE (valtype) == REFERENCE_TYPE) - { - if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR - || TREE_CODE (whats_returned) == TARGET_EXPR) - { - warning (OPT_Wreturn_local_addr, "returning reference to temporary"); - return; - } - if (TREE_CODE (whats_returned) == VAR_DECL - && DECL_NAME (whats_returned) - && TEMP_NAME_P (DECL_NAME (whats_returned))) - { - warning (OPT_Wreturn_local_addr, "reference to non-lvalue returned"); - return; - } - } - - while (TREE_CODE (whats_returned) == COMPONENT_REF - || TREE_CODE (whats_returned) == ARRAY_REF) - whats_returned = TREE_OPERAND (whats_returned, 0); - - if (DECL_P (whats_returned) - && DECL_NAME (whats_returned) - && DECL_FUNCTION_SCOPE_P (whats_returned) - && !(TREE_STATIC (whats_returned) - || TREE_PUBLIC (whats_returned))) - { - if (TREE_CODE (valtype) == REFERENCE_TYPE) - warning (OPT_Wreturn_local_addr, "reference to local variable %q+D returned", - whats_returned); - else - warning (OPT_Wreturn_local_addr, "address of local variable %q+D returned", - whats_returned); - return; - } -} - -/* Check that returning RETVAL from the current function is valid. - Return an expression explicitly showing all conversions required to - change RETVAL into the function return type, and to assign it to - the DECL_RESULT for the function. Set *NO_WARNING to true if - code reaches end of non-void function warning shouldn't be issued - on this RETURN_EXPR. */ - -tree -check_return_expr (tree retval, bool *no_warning) -{ - tree result; - /* The type actually returned by the function. */ - tree valtype; - /* The type the function is declared to return, or void if - the declared type is incomplete. */ - tree functype; - int fn_returns_value_p; - bool named_return_value_okay_p; - - *no_warning = false; - - /* A `volatile' function is one that isn't supposed to return, ever. - (This is a G++ extension, used to get better code for functions - that call the `volatile' function.) */ - if (TREE_THIS_VOLATILE (current_function_decl)) - warning (0, "function declared %<noreturn%> has a %<return%> statement"); - - /* Check for various simple errors. */ - if (DECL_DESTRUCTOR_P (current_function_decl)) - { - if (retval) - error ("returning a value from a destructor"); - return NULL_TREE; - } - else if (DECL_CONSTRUCTOR_P (current_function_decl)) - { - if (in_function_try_handler) - /* If a return statement appears in a handler of the - function-try-block of a constructor, the program is ill-formed. */ - error ("cannot return from a handler of a function-try-block of a constructor"); - else if (retval) - /* You can't return a value from a constructor. */ - error ("returning a value from a constructor"); - return NULL_TREE; - } - - if (processing_template_decl) - { - current_function_returns_value = 1; - if (check_for_bare_parameter_packs (retval)) - retval = error_mark_node; - return retval; - } - - functype = TREE_TYPE (TREE_TYPE (current_function_decl)); - - /* Deduce auto return type from a return statement. */ - if (current_function_auto_return_pattern) - { - tree auto_node; - tree type; - - if (!retval && !is_auto (current_function_auto_return_pattern)) - { - /* Give a helpful error message. */ - error ("return-statement with no value, in function returning %qT", - current_function_auto_return_pattern); - inform (input_location, "only plain %<auto%> return type can be " - "deduced to %<void%>"); - type = error_mark_node; - } - else if (retval && BRACE_ENCLOSED_INITIALIZER_P (retval)) - { - error ("returning initializer list"); - type = error_mark_node; - } - else - { - if (!retval) - retval = void_zero_node; - auto_node = type_uses_auto (current_function_auto_return_pattern); - type = do_auto_deduction (current_function_auto_return_pattern, - retval, auto_node); - } - - if (type == error_mark_node) - /* Leave it. */; - else if (functype == current_function_auto_return_pattern) - apply_deduced_return_type (current_function_decl, type); - else - /* A mismatch should have been diagnosed in do_auto_deduction. */ - gcc_assert (same_type_p (type, functype)); - functype = type; - } - - /* When no explicit return-value is given in a function with a named - return value, the named return value is used. */ - result = DECL_RESULT (current_function_decl); - valtype = TREE_TYPE (result); - gcc_assert (valtype != NULL_TREE); - fn_returns_value_p = !VOID_TYPE_P (valtype); - if (!retval && DECL_NAME (result) && fn_returns_value_p) - retval = result; - - /* Check for a return statement with no return value in a function - that's supposed to return a value. */ - if (!retval && fn_returns_value_p) - { - if (functype != error_mark_node) - permerror (input_location, "return-statement with no value, in " - "function returning %qT", valtype); - /* Remember that this function did return. */ - current_function_returns_value = 1; - /* And signal caller that TREE_NO_WARNING should be set on the - RETURN_EXPR to avoid control reaches end of non-void function - warnings in tree-cfg.c. */ - *no_warning = true; - } - /* Check for a return statement with a value in a function that - isn't supposed to return a value. */ - else if (retval && !fn_returns_value_p) - { - if (VOID_TYPE_P (TREE_TYPE (retval))) - /* You can return a `void' value from a function of `void' - type. In that case, we have to evaluate the expression for - its side-effects. */ - finish_expr_stmt (retval); - else - permerror (input_location, "return-statement with a value, in function " - "returning 'void'"); - current_function_returns_null = 1; - - /* There's really no value to return, after all. */ - return NULL_TREE; - } - else if (!retval) - /* Remember that this function can sometimes return without a - value. */ - current_function_returns_null = 1; - else - /* Remember that this function did return a value. */ - current_function_returns_value = 1; - - /* Check for erroneous operands -- but after giving ourselves a - chance to provide an error about returning a value from a void - function. */ - if (error_operand_p (retval)) - { - current_function_return_value = error_mark_node; - return error_mark_node; - } - - /* Only operator new(...) throw(), can return NULL [expr.new/13]. */ - if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR - || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR) - && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl)) - && ! flag_check_new - && retval && null_ptr_cst_p (retval)) - warning (0, "%<operator new%> must not return NULL unless it is " - "declared %<throw()%> (or -fcheck-new is in effect)"); - - /* Effective C++ rule 15. See also start_function. */ - if (warn_ecpp - && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR)) - { - bool warn = true; - - /* The function return type must be a reference to the current - class. */ - if (TREE_CODE (valtype) == REFERENCE_TYPE - && same_type_ignoring_top_level_qualifiers_p - (TREE_TYPE (valtype), TREE_TYPE (current_class_ref))) - { - /* Returning '*this' is obviously OK. */ - if (retval == current_class_ref) - warn = false; - /* If we are calling a function whose return type is the same of - the current class reference, it is ok. */ - else if (TREE_CODE (retval) == INDIRECT_REF - && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR) - warn = false; - } - - if (warn) - warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>"); - } - - /* The fabled Named Return Value optimization, as per [class.copy]/15: - - [...] For a function with a class return type, if the expression - in the return statement is the name of a local object, and the cv- - unqualified type of the local object is the same as the function - return type, an implementation is permitted to omit creating the tem- - porary object to hold the function return value [...] - - So, if this is a value-returning function that always returns the same - local variable, remember it. - - It might be nice to be more flexible, and choose the first suitable - variable even if the function sometimes returns something else, but - then we run the risk of clobbering the variable we chose if the other - returned expression uses the chosen variable somehow. And people expect - this restriction, anyway. (jason 2000-11-19) - - See finish_function and finalize_nrv for the rest of this optimization. */ - - named_return_value_okay_p = - (retval != NULL_TREE - /* Must be a local, automatic variable. */ - && TREE_CODE (retval) == VAR_DECL - && DECL_CONTEXT (retval) == current_function_decl - && ! TREE_STATIC (retval) - && ! DECL_ANON_UNION_VAR_P (retval) - && (DECL_ALIGN (retval) >= DECL_ALIGN (result)) - /* The cv-unqualified type of the returned value must be the - same as the cv-unqualified return type of the - function. */ - && same_type_p ((TYPE_MAIN_VARIANT (TREE_TYPE (retval))), - (TYPE_MAIN_VARIANT (functype))) - /* And the returned value must be non-volatile. */ - && ! TYPE_VOLATILE (TREE_TYPE (retval))); - - if (fn_returns_value_p && flag_elide_constructors) - { - if (named_return_value_okay_p - && (current_function_return_value == NULL_TREE - || current_function_return_value == retval)) - current_function_return_value = retval; - else - current_function_return_value = error_mark_node; - } - - /* We don't need to do any conversions when there's nothing being - returned. */ - if (!retval) - return NULL_TREE; - - /* Do any required conversions. */ - if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl)) - /* No conversions are required. */ - ; - else - { - int flags = LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING; - - /* The functype's return type will have been set to void, if it - was an incomplete type. Just treat this as 'return;' */ - if (VOID_TYPE_P (functype)) - return error_mark_node; - - /* Under C++0x [12.8/16 class.copy], a returned lvalue is sometimes - treated as an rvalue for the purposes of overload resolution to - favor move constructors over copy constructors. - - Note that these conditions are similar to, but not as strict as, - the conditions for the named return value optimization. */ - if ((cxx_dialect != cxx98) - && (TREE_CODE (retval) == VAR_DECL - || TREE_CODE (retval) == PARM_DECL) - && DECL_CONTEXT (retval) == current_function_decl - && !TREE_STATIC (retval) - && same_type_p ((TYPE_MAIN_VARIANT (TREE_TYPE (retval))), - (TYPE_MAIN_VARIANT (functype))) - /* This is only interesting for class type. */ - && CLASS_TYPE_P (functype)) - flags = flags | LOOKUP_PREFER_RVALUE; - - /* First convert the value to the function's return type, then - to the type of return value's location to handle the - case that functype is smaller than the valtype. */ - retval = convert_for_initialization - (NULL_TREE, functype, retval, flags, ICR_RETURN, NULL_TREE, 0, - tf_warning_or_error); - retval = convert (valtype, retval); - - /* If the conversion failed, treat this just like `return;'. */ - if (retval == error_mark_node) - return retval; - /* We can't initialize a register from a AGGR_INIT_EXPR. */ - else if (! cfun->returns_struct - && TREE_CODE (retval) == TARGET_EXPR - && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR) - retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval, - TREE_OPERAND (retval, 0)); - else - maybe_warn_about_returning_address_of_local (retval); - } - - /* Actually copy the value returned into the appropriate location. */ - if (retval && retval != result) - retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval); - - return retval; -} - - -/* Returns nonzero if the pointer-type FROM can be converted to the - pointer-type TO via a qualification conversion. If CONSTP is -1, - then we return nonzero if the pointers are similar, and the - cv-qualification signature of FROM is a proper subset of that of TO. - - If CONSTP is positive, then all outer pointers have been - const-qualified. */ - -static int -comp_ptr_ttypes_real (tree to, tree from, int constp) -{ - bool to_more_cv_qualified = false; - bool is_opaque_pointer = false; - - for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from)) - { - if (TREE_CODE (to) != TREE_CODE (from)) - return 0; - - if (TREE_CODE (from) == OFFSET_TYPE - && !same_type_p (TYPE_OFFSET_BASETYPE (from), - TYPE_OFFSET_BASETYPE (to))) - return 0; - - /* Const and volatile mean something different for function types, - so the usual checks are not appropriate. */ - if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE) - { - if (!at_least_as_qualified_p (to, from)) - return 0; - - if (!at_least_as_qualified_p (from, to)) - { - if (constp == 0) - return 0; - to_more_cv_qualified = true; - } - - if (constp > 0) - constp &= TYPE_READONLY (to); - } - - if (TREE_CODE (to) == VECTOR_TYPE) - is_opaque_pointer = vector_targets_convertible_p (to, from); - - if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRDATAMEM_P (to)) - return ((constp >= 0 || to_more_cv_qualified) - && (is_opaque_pointer - || same_type_ignoring_top_level_qualifiers_p (to, from))); - } -} - -/* When comparing, say, char ** to char const **, this function takes - the 'char *' and 'char const *'. Do not pass non-pointer/reference - types to this function. */ - -int -comp_ptr_ttypes (tree to, tree from) -{ - return comp_ptr_ttypes_real (to, from, 1); -} - -/* Returns true iff FNTYPE is a non-class type that involves - error_mark_node. We can get FUNCTION_TYPE with buried error_mark_node - if a parameter type is ill-formed. */ - -bool -error_type_p (const_tree type) -{ - tree t; - - switch (TREE_CODE (type)) - { - case ERROR_MARK: - return true; - - case POINTER_TYPE: - case REFERENCE_TYPE: - case OFFSET_TYPE: - return error_type_p (TREE_TYPE (type)); - - case FUNCTION_TYPE: - case METHOD_TYPE: - if (error_type_p (TREE_TYPE (type))) - return true; - for (t = TYPE_ARG_TYPES (type); t; t = TREE_CHAIN (t)) - if (error_type_p (TREE_VALUE (t))) - return true; - return false; - - case RECORD_TYPE: - if (TYPE_PTRMEMFUNC_P (type)) - return error_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type)); - return false; - - default: - return false; - } -} - -/* Returns 1 if to and from are (possibly multi-level) pointers to the same - type or inheritance-related types, regardless of cv-quals. */ - -int -ptr_reasonably_similar (const_tree to, const_tree from) -{ - for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from)) - { - /* Any target type is similar enough to void. */ - if (TREE_CODE (to) == VOID_TYPE) - return !error_type_p (from); - if (TREE_CODE (from) == VOID_TYPE) - return !error_type_p (to); - - if (TREE_CODE (to) != TREE_CODE (from)) - return 0; - - if (TREE_CODE (from) == OFFSET_TYPE - && comptypes (TYPE_OFFSET_BASETYPE (to), - TYPE_OFFSET_BASETYPE (from), - COMPARE_BASE | COMPARE_DERIVED)) - continue; - - if (TREE_CODE (to) == VECTOR_TYPE - && vector_types_convertible_p (to, from, false)) - return 1; - - if (TREE_CODE (to) == INTEGER_TYPE - && TYPE_PRECISION (to) == TYPE_PRECISION (from)) - return 1; - - if (TREE_CODE (to) == FUNCTION_TYPE) - return !error_type_p (to) && !error_type_p (from); - - if (TREE_CODE (to) != POINTER_TYPE) - return comptypes - (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from), - COMPARE_BASE | COMPARE_DERIVED); - } -} - -/* Return true if TO and FROM (both of which are POINTER_TYPEs or - pointer-to-member types) are the same, ignoring cv-qualification at - all levels. */ - -bool -comp_ptr_ttypes_const (tree to, tree from) -{ - bool is_opaque_pointer = false; - - for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from)) - { - if (TREE_CODE (to) != TREE_CODE (from)) - return false; - - if (TREE_CODE (from) == OFFSET_TYPE - && same_type_p (TYPE_OFFSET_BASETYPE (from), - TYPE_OFFSET_BASETYPE (to))) - continue; - - if (TREE_CODE (to) == VECTOR_TYPE) - is_opaque_pointer = vector_targets_convertible_p (to, from); - - if (TREE_CODE (to) != POINTER_TYPE) - return (is_opaque_pointer - || same_type_ignoring_top_level_qualifiers_p (to, from)); - } -} - -/* Returns the type qualifiers for this type, including the qualifiers on the - elements for an array type. */ - -int -cp_type_quals (const_tree type) -{ - int quals; - /* This CONST_CAST is okay because strip_array_types returns its - argument unmodified and we assign it to a const_tree. */ - type = strip_array_types (CONST_CAST_TREE (type)); - if (type == error_mark_node - /* Quals on a FUNCTION_TYPE are memfn quals. */ - || TREE_CODE (type) == FUNCTION_TYPE) - return TYPE_UNQUALIFIED; - quals = TYPE_QUALS (type); - /* METHOD and REFERENCE_TYPEs should never have quals. */ - gcc_assert ((TREE_CODE (type) != METHOD_TYPE - && TREE_CODE (type) != REFERENCE_TYPE) - || ((quals & (TYPE_QUAL_CONST|TYPE_QUAL_VOLATILE)) - == TYPE_UNQUALIFIED)); - return quals; -} - -/* Returns the function-ref-qualifier for TYPE */ - -cp_ref_qualifier -type_memfn_rqual (const_tree type) -{ - gcc_assert (TREE_CODE (type) == FUNCTION_TYPE - || TREE_CODE (type) == METHOD_TYPE); - - if (!FUNCTION_REF_QUALIFIED (type)) - return REF_QUAL_NONE; - else if (FUNCTION_RVALUE_QUALIFIED (type)) - return REF_QUAL_RVALUE; - else - return REF_QUAL_LVALUE; -} - -/* Returns the function-cv-quals for TYPE, which must be a FUNCTION_TYPE or - METHOD_TYPE. */ - -int -type_memfn_quals (const_tree type) -{ - if (TREE_CODE (type) == FUNCTION_TYPE) - return TYPE_QUALS (type); - else if (TREE_CODE (type) == METHOD_TYPE) - return cp_type_quals (class_of_this_parm (type)); - else - gcc_unreachable (); -} - -/* Returns the FUNCTION_TYPE TYPE with its function-cv-quals changed to - MEMFN_QUALS and its ref-qualifier to RQUAL. */ - -tree -apply_memfn_quals (tree type, cp_cv_quals memfn_quals, cp_ref_qualifier rqual) -{ - /* Could handle METHOD_TYPE here if necessary. */ - gcc_assert (TREE_CODE (type) == FUNCTION_TYPE); - if (TYPE_QUALS (type) == memfn_quals - && type_memfn_rqual (type) == rqual) - return type; - - /* This should really have a different TYPE_MAIN_VARIANT, but that gets - complex. */ - tree result = build_qualified_type (type, memfn_quals); - result = build_exception_variant (result, TYPE_RAISES_EXCEPTIONS (type)); - return build_ref_qualified_type (result, rqual); -} - -/* Returns nonzero if TYPE is const or volatile. */ - -bool -cv_qualified_p (const_tree type) -{ - int quals = cp_type_quals (type); - return (quals & (TYPE_QUAL_CONST|TYPE_QUAL_VOLATILE)) != 0; -} - -/* Returns nonzero if the TYPE contains a mutable member. */ - -bool -cp_has_mutable_p (const_tree type) -{ - /* This CONST_CAST is okay because strip_array_types returns its - argument unmodified and we assign it to a const_tree. */ - type = strip_array_types (CONST_CAST_TREE(type)); - - return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type); -} - -/* Set TREE_READONLY and TREE_VOLATILE on DECL as indicated by the - TYPE_QUALS. For a VAR_DECL, this may be an optimistic - approximation. In particular, consider: - - int f(); - struct S { int i; }; - const S s = { f(); } - - Here, we will make "s" as TREE_READONLY (because it is declared - "const") -- only to reverse ourselves upon seeing that the - initializer is non-constant. */ - -void -cp_apply_type_quals_to_decl (int type_quals, tree decl) -{ - tree type = TREE_TYPE (decl); - - if (type == error_mark_node) - return; - - if (TREE_CODE (decl) == TYPE_DECL) - return; - - gcc_assert (!(TREE_CODE (type) == FUNCTION_TYPE - && type_quals != TYPE_UNQUALIFIED)); - - /* Avoid setting TREE_READONLY incorrectly. */ - /* We used to check TYPE_NEEDS_CONSTRUCTING here, but now a constexpr - constructor can produce constant init, so rely on cp_finish_decl to - clear TREE_READONLY if the variable has non-constant init. */ - - /* If the type has (or might have) a mutable component, that component - might be modified. */ - if (TYPE_HAS_MUTABLE_P (type) || !COMPLETE_TYPE_P (type)) - type_quals &= ~TYPE_QUAL_CONST; - - c_apply_type_quals_to_decl (type_quals, decl); -} - -/* Subroutine of casts_away_constness. Make T1 and T2 point at - exemplar types such that casting T1 to T2 is casting away constness - if and only if there is no implicit conversion from T1 to T2. */ - -static void -casts_away_constness_r (tree *t1, tree *t2, tsubst_flags_t complain) -{ - int quals1; - int quals2; - - /* [expr.const.cast] - - For multi-level pointer to members and multi-level mixed pointers - and pointers to members (conv.qual), the "member" aspect of a - pointer to member level is ignored when determining if a const - cv-qualifier has been cast away. */ - /* [expr.const.cast] - - For two pointer types: - - X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type - X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type - K is min(N,M) - - casting from X1 to X2 casts away constness if, for a non-pointer - type T there does not exist an implicit conversion (clause - _conv_) from: - - Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N * - - to - - Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */ - if ((!TYPE_PTR_P (*t1) && !TYPE_PTRDATAMEM_P (*t1)) - || (!TYPE_PTR_P (*t2) && !TYPE_PTRDATAMEM_P (*t2))) - { - *t1 = cp_build_qualified_type (void_type_node, - cp_type_quals (*t1)); - *t2 = cp_build_qualified_type (void_type_node, - cp_type_quals (*t2)); - return; - } - - quals1 = cp_type_quals (*t1); - quals2 = cp_type_quals (*t2); - - if (TYPE_PTRDATAMEM_P (*t1)) - *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1); - else - *t1 = TREE_TYPE (*t1); - if (TYPE_PTRDATAMEM_P (*t2)) - *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2); - else - *t2 = TREE_TYPE (*t2); - - casts_away_constness_r (t1, t2, complain); - *t1 = build_pointer_type (*t1); - *t2 = build_pointer_type (*t2); - *t1 = cp_build_qualified_type (*t1, quals1); - *t2 = cp_build_qualified_type (*t2, quals2); -} - -/* Returns nonzero if casting from TYPE1 to TYPE2 casts away - constness. - - ??? This function returns non-zero if casting away qualifiers not - just const. We would like to return to the caller exactly which - qualifiers are casted away to give more accurate diagnostics. -*/ - -static bool -casts_away_constness (tree t1, tree t2, tsubst_flags_t complain) -{ - if (TREE_CODE (t2) == REFERENCE_TYPE) - { - /* [expr.const.cast] - - Casting from an lvalue of type T1 to an lvalue of type T2 - using a reference cast casts away constness if a cast from an - rvalue of type "pointer to T1" to the type "pointer to T2" - casts away constness. */ - t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1); - return casts_away_constness (build_pointer_type (t1), - build_pointer_type (TREE_TYPE (t2)), - complain); - } - - if (TYPE_PTRDATAMEM_P (t1) && TYPE_PTRDATAMEM_P (t2)) - /* [expr.const.cast] - - Casting from an rvalue of type "pointer to data member of X - of type T1" to the type "pointer to data member of Y of type - T2" casts away constness if a cast from an rvalue of type - "pointer to T1" to the type "pointer to T2" casts away - constness. */ - return casts_away_constness - (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)), - build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)), - complain); - - /* Casting away constness is only something that makes sense for - pointer or reference types. */ - if (TREE_CODE (t1) != POINTER_TYPE - || TREE_CODE (t2) != POINTER_TYPE) - return false; - - /* Top-level qualifiers don't matter. */ - t1 = TYPE_MAIN_VARIANT (t1); - t2 = TYPE_MAIN_VARIANT (t2); - casts_away_constness_r (&t1, &t2, complain); - if (!can_convert (t2, t1, complain)) - return true; - - return false; -} - -/* If T is a REFERENCE_TYPE return the type to which T refers. - Otherwise, return T itself. */ - -tree -non_reference (tree t) -{ - if (t && TREE_CODE (t) == REFERENCE_TYPE) - t = TREE_TYPE (t); - return t; -} - - -/* Return nonzero if REF is an lvalue valid for this language; - otherwise, print an error message and return zero. USE says - how the lvalue is being used and so selects the error message. */ - -int -lvalue_or_else (tree ref, enum lvalue_use use, tsubst_flags_t complain) -{ - cp_lvalue_kind kind = lvalue_kind (ref); - - if (kind == clk_none) - { - if (complain & tf_error) - lvalue_error (input_location, use); - return 0; - } - else if (kind & (clk_rvalueref|clk_class)) - { - if (!(complain & tf_error)) - return 0; - if (kind & clk_class) - /* Make this a permerror because we used to accept it. */ - permerror (input_location, "using temporary as lvalue"); - else - error ("using xvalue (rvalue reference) as lvalue"); - } - return 1; -} - -/* Return true if a user-defined literal operator is a raw operator. */ - -bool -check_raw_literal_operator (const_tree decl) -{ - tree argtypes = TYPE_ARG_TYPES (TREE_TYPE (decl)); - tree argtype; - int arity; - bool maybe_raw_p = false; - - /* Count the number and type of arguments and check for ellipsis. */ - for (argtype = argtypes, arity = 0; - argtype && argtype != void_list_node; - ++arity, argtype = TREE_CHAIN (argtype)) - { - tree t = TREE_VALUE (argtype); - - if (same_type_p (t, const_string_type_node)) - maybe_raw_p = true; - } - if (!argtype) - return false; /* Found ellipsis. */ - - if (!maybe_raw_p || arity != 1) - return false; - - return true; -} - - -/* Return true if a user-defined literal operator has one of the allowed - argument types. */ - -bool -check_literal_operator_args (const_tree decl, - bool *long_long_unsigned_p, bool *long_double_p) -{ - tree argtypes = TYPE_ARG_TYPES (TREE_TYPE (decl)); - - *long_long_unsigned_p = false; - *long_double_p = false; - if (processing_template_decl || processing_specialization) - return argtypes == void_list_node; - else - { - tree argtype; - int arity; - int max_arity = 2; - - /* Count the number and type of arguments and check for ellipsis. */ - for (argtype = argtypes, arity = 0; - argtype && argtype != void_list_node; - argtype = TREE_CHAIN (argtype)) - { - tree t = TREE_VALUE (argtype); - ++arity; - - if (TREE_CODE (t) == POINTER_TYPE) - { - bool maybe_raw_p = false; - t = TREE_TYPE (t); - if (cp_type_quals (t) != TYPE_QUAL_CONST) - return false; - t = TYPE_MAIN_VARIANT (t); - if ((maybe_raw_p = same_type_p (t, char_type_node)) - || same_type_p (t, wchar_type_node) - || same_type_p (t, char16_type_node) - || same_type_p (t, char32_type_node)) - { - argtype = TREE_CHAIN (argtype); - if (!argtype) - return false; - t = TREE_VALUE (argtype); - if (maybe_raw_p && argtype == void_list_node) - return true; - else if (same_type_p (t, size_type_node)) - { - ++arity; - continue; - } - else - return false; - } - } - else if (same_type_p (t, long_long_unsigned_type_node)) - { - max_arity = 1; - *long_long_unsigned_p = true; - } - else if (same_type_p (t, long_double_type_node)) - { - max_arity = 1; - *long_double_p = true; - } - else if (same_type_p (t, char_type_node)) - max_arity = 1; - else if (same_type_p (t, wchar_type_node)) - max_arity = 1; - else if (same_type_p (t, char16_type_node)) - max_arity = 1; - else if (same_type_p (t, char32_type_node)) - max_arity = 1; - else - return false; - } - if (!argtype) - return false; /* Found ellipsis. */ - - if (arity != max_arity) - return false; - - return true; - } -} |