diff options
Diffstat (limited to 'gcc-4.2.1-5666.3/gcc/cp/call.c')
| -rw-r--r-- | gcc-4.2.1-5666.3/gcc/cp/call.c | 6871 |
1 files changed, 6871 insertions, 0 deletions
diff --git a/gcc-4.2.1-5666.3/gcc/cp/call.c b/gcc-4.2.1-5666.3/gcc/cp/call.c new file mode 100644 index 000000000..66669e2e5 --- /dev/null +++ b/gcc-4.2.1-5666.3/gcc/cp/call.c @@ -0,0 +1,6871 @@ +/* Functions related to invoking methods and overloaded functions. + Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998, + 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. + Contributed by Michael Tiemann (tiemann@cygnus.com) and + modified by Brendan Kehoe (brendan@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 2, 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 COPYING. If not, write to +the Free Software Foundation, 51 Franklin Street, Fifth Floor, +Boston, MA 02110-1301, USA. */ + + +/* High-level class interface. */ + +#include "config.h" +#include "system.h" +#include "coretypes.h" +#include "tm.h" +#include "tree.h" +#include "cp-tree.h" +#include "output.h" +#include "flags.h" +#include "rtl.h" +#include "toplev.h" +#include "expr.h" +#include "diagnostic.h" +#include "intl.h" +#include "target.h" +#include "convert.h" + +/* The various kinds of conversion. */ + +typedef enum conversion_kind { + ck_identity, + ck_lvalue, + ck_qual, + ck_std, + ck_ptr, + ck_pmem, + ck_base, + ck_ref_bind, + ck_user, + ck_ambig, + ck_rvalue +} conversion_kind; + +/* The rank of the conversion. Order of the enumerals matters; better + conversions should come earlier in the list. */ + +typedef enum conversion_rank { + cr_identity, + cr_exact, + cr_promotion, + cr_std, + cr_pbool, + cr_user, + cr_ellipsis, + cr_bad +} conversion_rank; + +/* An implicit conversion sequence, in the sense of [over.best.ics]. + The first conversion to be performed is at the end of the chain. + That conversion is always a cr_identity conversion. */ + +typedef struct conversion conversion; +struct conversion { + /* The kind of conversion represented by this step. */ + conversion_kind kind; + /* The rank of this conversion. */ + conversion_rank rank; + BOOL_BITFIELD user_conv_p : 1; + BOOL_BITFIELD ellipsis_p : 1; + BOOL_BITFIELD this_p : 1; + BOOL_BITFIELD bad_p : 1; + /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a + temporary should be created to hold the result of the + conversion. */ + BOOL_BITFIELD need_temporary_p : 1; + /* If KIND is ck_identity or ck_base_conv, true to indicate that the + copy constructor must be accessible, even though it is not being + used. */ + BOOL_BITFIELD check_copy_constructor_p : 1; + /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion + from a pointer-to-derived to pointer-to-base is being performed. */ + BOOL_BITFIELD base_p : 1; + /* The type of the expression resulting from the conversion. */ + tree type; + union { + /* The next conversion in the chain. Since the conversions are + arranged from outermost to innermost, the NEXT conversion will + actually be performed before this conversion. This variant is + used only when KIND is neither ck_identity nor ck_ambig. */ + conversion *next; + /* The expression at the beginning of the conversion chain. This + variant is used only if KIND is ck_identity or ck_ambig. */ + tree expr; + } u; + /* The function candidate corresponding to this conversion + sequence. This field is only used if KIND is ck_user. */ + struct z_candidate *cand; +}; + +#define CONVERSION_RANK(NODE) \ + ((NODE)->bad_p ? cr_bad \ + : (NODE)->ellipsis_p ? cr_ellipsis \ + : (NODE)->user_conv_p ? cr_user \ + : (NODE)->rank) + +static struct obstack conversion_obstack; +static bool conversion_obstack_initialized; + +static struct z_candidate * tourney (struct z_candidate *); +static int equal_functions (tree, tree); +static int joust (struct z_candidate *, struct z_candidate *, bool); +static int compare_ics (conversion *, conversion *); +static tree build_over_call (struct z_candidate *, int); +static tree build_java_interface_fn_ref (tree, tree); +#define convert_like(CONV, EXPR) \ + convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \ + /*issue_conversion_warnings=*/true, \ + /*c_cast_p=*/false) +#define convert_like_with_context(CONV, EXPR, FN, ARGNO) \ + convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \ + /*issue_conversion_warnings=*/true, \ + /*c_cast_p=*/false) +static tree convert_like_real (conversion *, tree, tree, int, int, bool, + bool); +static void op_error (enum tree_code, enum tree_code, tree, tree, + tree, const char *); +static tree build_object_call (tree, tree); +static tree resolve_args (tree); +static struct z_candidate *build_user_type_conversion_1 (tree, tree, int); +static void print_z_candidate (const char *, struct z_candidate *); +static void print_z_candidates (struct z_candidate *); +static tree build_this (tree); +static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *); +static bool any_strictly_viable (struct z_candidate *); +static struct z_candidate *add_template_candidate + (struct z_candidate **, tree, tree, tree, tree, tree, + tree, tree, int, unification_kind_t); +static struct z_candidate *add_template_candidate_real + (struct z_candidate **, tree, tree, tree, tree, tree, + tree, tree, int, tree, unification_kind_t); +static struct z_candidate *add_template_conv_candidate + (struct z_candidate **, tree, tree, tree, tree, tree, tree); +static void add_builtin_candidates + (struct z_candidate **, enum tree_code, enum tree_code, + tree, tree *, int); +static void add_builtin_candidate + (struct z_candidate **, enum tree_code, enum tree_code, + tree, tree, tree, tree *, tree *, int); +static bool is_complete (tree); +static void build_builtin_candidate + (struct z_candidate **, tree, tree, tree, tree *, tree *, + int); +static struct z_candidate *add_conv_candidate + (struct z_candidate **, tree, tree, tree, tree, tree); +static struct z_candidate *add_function_candidate + (struct z_candidate **, tree, tree, tree, tree, tree, int); +static conversion *implicit_conversion (tree, tree, tree, bool, int); +static conversion *standard_conversion (tree, tree, tree, bool, int); +static conversion *reference_binding (tree, tree, tree, bool, int); +static conversion *build_conv (conversion_kind, tree, conversion *); +static bool is_subseq (conversion *, conversion *); +static tree maybe_handle_ref_bind (conversion **); +static void maybe_handle_implicit_object (conversion **); +static struct z_candidate *add_candidate + (struct z_candidate **, tree, tree, size_t, + conversion **, tree, tree, int); +static tree source_type (conversion *); +static void add_warning (struct z_candidate *, struct z_candidate *); +static bool reference_related_p (tree, tree); +static bool reference_compatible_p (tree, tree); +static conversion *convert_class_to_reference (tree, tree, tree); +static conversion *direct_reference_binding (tree, conversion *); +static bool promoted_arithmetic_type_p (tree); +static conversion *conditional_conversion (tree, tree); +static char *name_as_c_string (tree, tree, bool *); +static tree call_builtin_trap (void); +static tree prep_operand (tree); +static void add_candidates (tree, tree, tree, bool, tree, tree, + int, struct z_candidate **); +static conversion *merge_conversion_sequences (conversion *, conversion *); +static bool magic_varargs_p (tree); +typedef void (*diagnostic_fn_t) (const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2); +static tree build_temp (tree, tree, int, diagnostic_fn_t *); +static void check_constructor_callable (tree, tree); + +/* Returns nonzero iff the destructor name specified in NAME matches BASETYPE. + NAME can take many forms... */ + +bool +check_dtor_name (tree basetype, tree name) +{ + /* Just accept something we've already complained about. */ + if (name == error_mark_node) + return true; + + if (TREE_CODE (name) == TYPE_DECL) + name = TREE_TYPE (name); + else if (TYPE_P (name)) + /* OK */; + else if (TREE_CODE (name) == IDENTIFIER_NODE) + { + if ((IS_AGGR_TYPE (basetype) && name == constructor_name (basetype)) + || (TREE_CODE (basetype) == ENUMERAL_TYPE + && name == TYPE_IDENTIFIER (basetype))) + return true; + else + name = get_type_value (name); + } + else + { + /* In the case of: + + template <class T> struct S { ~S(); }; + int i; + i.~S(); + + NAME will be a class template. */ + gcc_assert (DECL_CLASS_TEMPLATE_P (name)); + return false; + } + + if (!name) + return false; + return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name)); +} + +/* We want the address of a function or method. We avoid creating a + pointer-to-member function. */ + +tree +build_addr_func (tree function) +{ + tree type = TREE_TYPE (function); + + /* We have to do these by hand to avoid real pointer to member + functions. */ + if (TREE_CODE (type) == METHOD_TYPE) + { + if (TREE_CODE (function) == OFFSET_REF) + { + tree object = build_address (TREE_OPERAND (function, 0)); + return get_member_function_from_ptrfunc (&object, + TREE_OPERAND (function, 1)); + } + function = build_address (function); + } + else + function = decay_conversion (function); + + return function; +} + +/* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or + POINTER_TYPE to those. Note, pointer to member function types + (TYPE_PTRMEMFUNC_P) must be handled by our callers. */ + +tree +build_call (tree function, tree parms) +{ + int is_constructor = 0; + int nothrow; + tree tmp; + tree decl; + tree result_type; + tree fntype; + + function = build_addr_func (function); + + /* APPLE LOCAL blocks 6040305 */ + gcc_assert (TYPE_PTR_P (TREE_TYPE (function)) || TREE_CODE (TREE_TYPE (function)) == BLOCK_POINTER_TYPE); + fntype = TREE_TYPE (TREE_TYPE (function)); + gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE + || TREE_CODE (fntype) == METHOD_TYPE); + result_type = TREE_TYPE (fntype); + + if (TREE_CODE (function) == ADDR_EXPR + && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL) + { + decl = TREE_OPERAND (function, 0); + if (!TREE_USED (decl)) + { + /* We invoke build_call directly for several library + functions. These may have been declared normally if + we're building libgcc, so we can't just check + DECL_ARTIFICIAL. */ + gcc_assert (DECL_ARTIFICIAL (decl) + || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)), + "__", 2)); + mark_used (decl); + } + } + else + decl = NULL_TREE; + + /* We check both the decl and the type; a function may be known not to + throw without being declared throw(). */ + nothrow = ((decl && TREE_NOTHROW (decl)) + || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function)))); + + if (decl && TREE_THIS_VOLATILE (decl) && cfun) + current_function_returns_abnormally = 1; + + if (decl && TREE_DEPRECATED (decl)) + warn_deprecated_use (decl); + require_complete_eh_spec_types (fntype, decl); + + if (decl && DECL_CONSTRUCTOR_P (decl)) + is_constructor = 1; + + /* Don't pass empty class objects by value. This is useful + for tags in STL, which are used to control overload resolution. + We don't need to handle other cases of copying empty classes. */ + if (! decl || ! DECL_BUILT_IN (decl)) + for (tmp = parms; tmp; tmp = TREE_CHAIN (tmp)) + if (is_empty_class (TREE_TYPE (TREE_VALUE (tmp))) + && ! TREE_ADDRESSABLE (TREE_TYPE (TREE_VALUE (tmp)))) + { + tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (TREE_VALUE (tmp))); + TREE_VALUE (tmp) = build2 (COMPOUND_EXPR, TREE_TYPE (t), + TREE_VALUE (tmp), t); + } + + function = build3 (CALL_EXPR, result_type, function, parms, NULL_TREE); + TREE_HAS_CONSTRUCTOR (function) = is_constructor; + TREE_NOTHROW (function) = nothrow; + + return function; +} + +/* Build something of the form ptr->method (args) + or object.method (args). This can also build + calls to constructors, and find friends. + + Member functions always take their class variable + as a pointer. + + INSTANCE is a class instance. + + NAME is the name of the method desired, usually an IDENTIFIER_NODE. + + PARMS help to figure out what that NAME really refers to. + + BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE + down to the real instance type to use for access checking. We need this + information to get protected accesses correct. + + FLAGS is the logical disjunction of zero or more LOOKUP_ + flags. See cp-tree.h for more info. + + If this is all OK, calls build_function_call with the resolved + member function. + + This function must also handle being called to perform + initialization, promotion/coercion of arguments, and + instantiation of default parameters. + + Note that NAME may refer to an instance variable name. If + `operator()()' is defined for the type of that field, then we return + that result. */ + +/* New overloading code. */ + +typedef struct z_candidate z_candidate; + +typedef struct candidate_warning candidate_warning; +struct candidate_warning { + z_candidate *loser; + candidate_warning *next; +}; + +struct z_candidate { + /* The FUNCTION_DECL that will be called if this candidate is + selected by overload resolution. */ + tree fn; + /* The arguments to use when calling this function. */ + tree args; + /* The implicit conversion sequences for each of the arguments to + FN. */ + conversion **convs; + /* The number of implicit conversion sequences. */ + size_t num_convs; + /* If FN is a user-defined conversion, the standard conversion + sequence from the type returned by FN to the desired destination + type. */ + conversion *second_conv; + int viable; + /* If FN is a member function, the binfo indicating the path used to + qualify the name of FN at the call site. This path is used to + determine whether or not FN is accessible if it is selected by + overload resolution. The DECL_CONTEXT of FN will always be a + (possibly improper) base of this binfo. */ + tree access_path; + /* If FN is a non-static member function, the binfo indicating the + subobject to which the `this' pointer should be converted if FN + is selected by overload resolution. The type pointed to the by + the `this' pointer must correspond to the most derived class + indicated by the CONVERSION_PATH. */ + tree conversion_path; + tree template_decl; + candidate_warning *warnings; + z_candidate *next; +}; + +/* Returns true iff T is a null pointer constant in the sense of + [conv.ptr]. */ + +bool +null_ptr_cst_p (tree t) +{ + /* [conv.ptr] + + A null pointer constant is an integral constant expression + (_expr.const_) rvalue of integer type that evaluates to zero. */ + t = integral_constant_value (t); + if (t == null_node) + return true; + if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t)) + { + STRIP_NOPS (t); + if (!TREE_CONSTANT_OVERFLOW (t)) + return true; + } + return false; +} + +/* Returns nonzero if PARMLIST consists of only default parms and/or + ellipsis. */ + +bool +sufficient_parms_p (tree parmlist) +{ + for (; parmlist && parmlist != void_list_node; + parmlist = TREE_CHAIN (parmlist)) + if (!TREE_PURPOSE (parmlist)) + return false; + return true; +} + +/* Allocate N bytes of memory from the conversion obstack. The memory + is zeroed before being returned. */ + +static void * +conversion_obstack_alloc (size_t n) +{ + void *p; + if (!conversion_obstack_initialized) + { + gcc_obstack_init (&conversion_obstack); + conversion_obstack_initialized = true; + } + p = obstack_alloc (&conversion_obstack, n); + memset (p, 0, n); + return p; +} + +/* Dynamically allocate a conversion. */ + +static conversion * +alloc_conversion (conversion_kind kind) +{ + conversion *c; + c = (conversion *) conversion_obstack_alloc (sizeof (conversion)); + c->kind = kind; + return c; +} + +#ifdef ENABLE_CHECKING + +/* Make sure that all memory on the conversion obstack has been + freed. */ + +void +validate_conversion_obstack (void) +{ + if (conversion_obstack_initialized) + gcc_assert ((obstack_next_free (&conversion_obstack) + == obstack_base (&conversion_obstack))); +} + +#endif /* ENABLE_CHECKING */ + +/* Dynamically allocate an array of N conversions. */ + +static conversion ** +alloc_conversions (size_t n) +{ + return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *)); +} + +static conversion * +build_conv (conversion_kind code, tree type, conversion *from) +{ + conversion *t; + conversion_rank rank = CONVERSION_RANK (from); + + /* We can't use buildl1 here because CODE could be USER_CONV, which + takes two arguments. In that case, the caller is responsible for + filling in the second argument. */ + t = alloc_conversion (code); + t->type = type; + t->u.next = from; + + switch (code) + { + case ck_ptr: + case ck_pmem: + case ck_base: + case ck_std: + if (rank < cr_std) + rank = cr_std; + break; + + case ck_qual: + if (rank < cr_exact) + rank = cr_exact; + break; + + default: + break; + } + t->rank = rank; + t->user_conv_p = (code == ck_user || from->user_conv_p); + t->bad_p = from->bad_p; + t->base_p = false; + return t; +} + +/* Build a representation of the identity conversion from EXPR to + itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */ + +static conversion * +build_identity_conv (tree type, tree expr) +{ + conversion *c; + + c = alloc_conversion (ck_identity); + c->type = type; + c->u.expr = expr; + + return c; +} + +/* Converting from EXPR to TYPE was ambiguous in the sense that there + were multiple user-defined conversions to accomplish the job. + Build a conversion that indicates that ambiguity. */ + +static conversion * +build_ambiguous_conv (tree type, tree expr) +{ + conversion *c; + + c = alloc_conversion (ck_ambig); + c->type = type; + c->u.expr = expr; + + return c; +} + +tree +strip_top_quals (tree t) +{ + if (TREE_CODE (t) == ARRAY_TYPE) + return t; + return cp_build_qualified_type (t, 0); +} + +/* Returns the standard conversion path (see [conv]) from type FROM to type + TO, if any. For proper handling of null pointer constants, you must + also pass the expression EXPR to convert from. If C_CAST_P is true, + this conversion is coming from a C-style cast. */ + +static conversion * +standard_conversion (tree to, tree from, tree expr, bool c_cast_p, + int flags) +{ + enum tree_code fcode, tcode; + conversion *conv; + bool fromref = false; + + to = non_reference (to); + if (TREE_CODE (from) == REFERENCE_TYPE) + { + fromref = true; + from = TREE_TYPE (from); + } + to = strip_top_quals (to); + from = strip_top_quals (from); + + if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to)) + && expr && type_unknown_p (expr)) + { + expr = instantiate_type (to, expr, tf_conv); + if (expr == error_mark_node) + return NULL; + from = TREE_TYPE (expr); + } + + fcode = TREE_CODE (from); + tcode = TREE_CODE (to); + + conv = build_identity_conv (from, expr); + if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE) + { + from = type_decays_to (from); + fcode = TREE_CODE (from); + conv = build_conv (ck_lvalue, from, conv); + } + else if (fromref || (expr && lvalue_p (expr))) + { + if (expr) + { + tree bitfield_type; + bitfield_type = is_bitfield_expr_with_lowered_type (expr); + if (bitfield_type) + { + from = strip_top_quals (bitfield_type); + fcode = TREE_CODE (from); + } + } + conv = build_conv (ck_rvalue, from, conv); + } + + /* Allow conversion between `__complex__' data types. */ + if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE) + { + /* The standard conversion sequence to convert FROM to TO is + the standard conversion sequence to perform componentwise + conversion. */ + conversion *part_conv = standard_conversion + (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags); + + if (part_conv) + { + conv = build_conv (part_conv->kind, to, conv); + conv->rank = part_conv->rank; + } + else + conv = NULL; + + return conv; + } + + if (same_type_p (from, to)) + return conv; + + /* APPLE LOCAL blocks 6040305 (ck) */ + if ((tcode == POINTER_TYPE || tcode == BLOCK_POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to)) + && expr && null_ptr_cst_p (expr)) + conv = build_conv (ck_std, to, conv); + else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE) + || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE)) + { + /* For backwards brain damage compatibility, allow interconversion of + pointers and integers with a pedwarn. */ + conv = build_conv (ck_std, to, conv); + conv->bad_p = true; + } + else if (tcode == ENUMERAL_TYPE && fcode == INTEGER_TYPE) + { + /* For backwards brain damage compatibility, allow interconversion of + enums and integers with a pedwarn. */ + conv = build_conv (ck_std, to, conv); + conv->bad_p = true; + } + /* APPLE LOCAL begin blocks (ck) */ + else if (tcode == POINTER_TYPE && fcode == BLOCK_POINTER_TYPE + && (objc_is_id (to) + || VOID_TYPE_P (TREE_TYPE (to)))) + { + conv = build_conv (ck_ptr, to, conv); + } + else if (tcode == BLOCK_POINTER_TYPE && objc_is_id (from)) + { + conv = build_conv (ck_ptr, to, conv); + } + /* APPLE LOCAL end blocks (ck) */ + else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE) + || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from))) + { + tree to_pointee; + tree from_pointee; + + if (tcode == POINTER_TYPE + && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from), + TREE_TYPE (to))) + ; + else if (VOID_TYPE_P (TREE_TYPE (to)) + && !TYPE_PTRMEM_P (from) + && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE) + { + /* APPLE LOCAL begin radar 4451818 */ + tree nfrom = TREE_TYPE (from); + if (c_dialect_objc ()) + nfrom = objc_non_volatilized_type (nfrom); + from = build_pointer_type + (cp_build_qualified_type (void_type_node, + cp_type_quals (nfrom))); + /* APPLE LOCAL end radar 4451818 */ + conv = build_conv (ck_ptr, from, conv); + } + else if (TYPE_PTRMEM_P (from)) + { + tree fbase = TYPE_PTRMEM_CLASS_TYPE (from); + tree tbase = TYPE_PTRMEM_CLASS_TYPE (to); + + if (DERIVED_FROM_P (fbase, tbase) + && (same_type_ignoring_top_level_qualifiers_p + (TYPE_PTRMEM_POINTED_TO_TYPE (from), + TYPE_PTRMEM_POINTED_TO_TYPE (to)))) + { + from = build_ptrmem_type (tbase, + TYPE_PTRMEM_POINTED_TO_TYPE (from)); + conv = build_conv (ck_pmem, from, conv); + } + else if (!same_type_p (fbase, tbase)) + return NULL; + } + else if (IS_AGGR_TYPE (TREE_TYPE (from)) + && IS_AGGR_TYPE (TREE_TYPE (to)) + /* [conv.ptr] + + An rvalue of type "pointer to cv D," where D is a + class type, can be converted to an rvalue of type + "pointer to cv B," where B is a base class (clause + _class.derived_) of D. If B is an inaccessible + (clause _class.access_) or ambiguous + (_class.member.lookup_) base class of D, a program + that necessitates this conversion is ill-formed. + Therefore, we use DERIVED_FROM_P, and do not check + access or uniqueness. */ + && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)) + /* If FROM is not yet complete, then we must be parsing + the body of a class. We know what's derived from + what, but we can't actually perform a + derived-to-base conversion. For example, in: + + struct D : public B { + static const int i = sizeof((B*)(D*)0); + }; + + the D*-to-B* conversion is a reinterpret_cast, not a + static_cast. */ + && COMPLETE_TYPE_P (TREE_TYPE (from))) + { + /* APPLE LOCAL begin radar 4668465 */ + tree fr = c_dialect_objc () ? + objc_non_volatilized_type (TREE_TYPE (from)) + : TREE_TYPE (from); + from = + cp_build_qualified_type (TREE_TYPE (to), + cp_type_quals (fr)); + /* APPLE LOCAL end radar 4668465 */ + from = build_pointer_type (from); + conv = build_conv (ck_ptr, from, conv); + conv->base_p = true; + } + + if (tcode == POINTER_TYPE) + { + to_pointee = TREE_TYPE (to); + from_pointee = TREE_TYPE (from); + } + else + { + to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to); + from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from); + } + + if (same_type_p (from, to)) + /* OK */; + else if (c_cast_p && comp_ptr_ttypes_const (to, from)) + /* In a C-style cast, we ignore CV-qualification because we + are allowed to perform a static_cast followed by a + const_cast. */ + conv = build_conv (ck_qual, to, conv); + else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee)) + conv = build_conv (ck_qual, to, conv); + else if (expr && string_conv_p (to, expr, 0)) + /* converting from string constant to char *. */ + conv = build_conv (ck_qual, to, conv); + /* APPLE LOCAL begin 4154928 */ + /* Allow conversions among compatible ObjC pointer types (base + conversions have been already handled above). */ + else if (c_dialect_objc () + /* APPLE LOCAL radar 6231433 */ + && objc_compare_types (to, from, -4, NULL_TREE, NULL)) + conv = build_conv (ck_ptr, to, conv); + /* APPLE LOCAL end 4154928 */ + else if (ptr_reasonably_similar (to_pointee, from_pointee)) + { + conv = build_conv (ck_ptr, to, conv); + conv->bad_p = true; + } + else + return NULL; + + from = to; + } + else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from)) + { + tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from)); + tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to)); + tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn))); + tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn))); + + if (!DERIVED_FROM_P (fbase, tbase) + || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn)) + || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)), + TREE_CHAIN (TYPE_ARG_TYPES (tofn))) + || cp_type_quals (fbase) != cp_type_quals (tbase)) + return NULL; + + from = cp_build_qualified_type (tbase, cp_type_quals (fbase)); + from = build_method_type_directly (from, + TREE_TYPE (fromfn), + TREE_CHAIN (TYPE_ARG_TYPES (fromfn))); + from = build_ptrmemfunc_type (build_pointer_type (from)); + conv = build_conv (ck_pmem, from, conv); + conv->base_p = true; + } + else if (tcode == BOOLEAN_TYPE) + { + /* [conv.bool] + + An rvalue of arithmetic, enumeration, pointer, or pointer to + member type can be converted to an rvalue of type bool. */ + if (ARITHMETIC_TYPE_P (from) + || fcode == ENUMERAL_TYPE + || fcode == POINTER_TYPE + /* APPLE LOCAL blocks 6040305 (cl) */ + || fcode == BLOCK_POINTER_TYPE + || TYPE_PTR_TO_MEMBER_P (from)) + { + conv = build_conv (ck_std, to, conv); + if (fcode == POINTER_TYPE + || TYPE_PTRMEM_P (from) + || (TYPE_PTRMEMFUNC_P (from) + && conv->rank < cr_pbool)) + conv->rank = cr_pbool; + return conv; + } + + return NULL; + } + /* We don't check for ENUMERAL_TYPE here because there are no standard + conversions to enum type. */ + else if (tcode == INTEGER_TYPE || tcode == BOOLEAN_TYPE + || tcode == REAL_TYPE) + { + if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE)) + return NULL; + conv = build_conv (ck_std, to, conv); + + /* Give this a better rank if it's a promotion. */ + if (same_type_p (to, type_promotes_to (from)) + && conv->u.next->rank <= cr_promotion) + conv->rank = cr_promotion; + } + else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE + /* APPLE LOCAL 5612787 mainline sse4 */ + && vector_types_convertible_p (from, to, false)) + return build_conv (ck_std, to, conv); + else if (!(flags & LOOKUP_CONSTRUCTOR_CALLABLE) + && IS_AGGR_TYPE (to) && IS_AGGR_TYPE (from) + && is_properly_derived_from (from, to)) + { + if (conv->kind == ck_rvalue) + conv = conv->u.next; + conv = build_conv (ck_base, to, conv); + /* The derived-to-base conversion indicates the initialization + of a parameter with base type from an object of a derived + type. A temporary object is created to hold the result of + the conversion. */ + conv->need_temporary_p = true; + } + else + return NULL; + + return conv; +} + +/* Returns nonzero if T1 is reference-related to T2. */ + +static bool +reference_related_p (tree t1, tree t2) +{ + t1 = TYPE_MAIN_VARIANT (t1); + t2 = TYPE_MAIN_VARIANT (t2); + + /* [dcl.init.ref] + + Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related + to "cv2 T2" if T1 is the same type as T2, or T1 is a base class + of T2. */ + return (same_type_p (t1, t2) + || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2) + && DERIVED_FROM_P (t1, t2))); +} + +/* APPLE LOCAL begin radar 6029624 */ +/* Used in objective-c++, same as reference_related_p */ +bool +objcp_reference_related_p (tree t1, tree t2) +{ + return reference_related_p (t1, t2); +} +/* APPLE LOCAL end radar 6029624 */ + +/* Returns nonzero if T1 is reference-compatible with T2. */ + +static bool +reference_compatible_p (tree t1, tree t2) +{ + /* [dcl.init.ref] + + "cv1 T1" is reference compatible with "cv2 T2" if T1 is + reference-related to T2 and cv1 is the same cv-qualification as, + or greater cv-qualification than, cv2. */ + return (reference_related_p (t1, t2) + && at_least_as_qualified_p (t1, t2)); +} + +/* Determine whether or not the EXPR (of class type S) can be + converted to T as in [over.match.ref]. */ + +static conversion * +convert_class_to_reference (tree t, tree s, tree expr) +{ + tree conversions; + tree arglist; + conversion *conv; + tree reference_type; + struct z_candidate *candidates; + struct z_candidate *cand; + bool any_viable_p; + + conversions = lookup_conversions (s); + if (!conversions) + return NULL; + + /* [over.match.ref] + + Assuming that "cv1 T" is the underlying type of the reference + being initialized, and "cv S" is the type of the initializer + expression, with S a class type, the candidate functions are + selected as follows: + + --The conversion functions of S and its base classes are + considered. Those that are not hidden within S and yield type + "reference to cv2 T2", where "cv1 T" is reference-compatible + (_dcl.init.ref_) with "cv2 T2", are candidate functions. + + The argument list has one argument, which is the initializer + expression. */ + + candidates = 0; + + /* Conceptually, we should take the address of EXPR and put it in + the argument list. Unfortunately, however, that can result in + error messages, which we should not issue now because we are just + trying to find a conversion operator. Therefore, we use NULL, + cast to the appropriate type. */ + arglist = build_int_cst (build_pointer_type (s), 0); + arglist = build_tree_list (NULL_TREE, arglist); + + reference_type = build_reference_type (t); + + while (conversions) + { + tree fns = TREE_VALUE (conversions); + + for (; fns; fns = OVL_NEXT (fns)) + { + tree f = OVL_CURRENT (fns); + tree t2 = TREE_TYPE (TREE_TYPE (f)); + + cand = NULL; + + /* If this is a template function, try to get an exact + match. */ + if (TREE_CODE (f) == TEMPLATE_DECL) + { + cand = add_template_candidate (&candidates, + f, s, + NULL_TREE, + arglist, + reference_type, + TYPE_BINFO (s), + TREE_PURPOSE (conversions), + LOOKUP_NORMAL, + DEDUCE_CONV); + + if (cand) + { + /* Now, see if the conversion function really returns + an lvalue of the appropriate type. From the + point of view of unification, simply returning an + rvalue of the right type is good enough. */ + f = cand->fn; + t2 = TREE_TYPE (TREE_TYPE (f)); + if (TREE_CODE (t2) != REFERENCE_TYPE + || !reference_compatible_p (t, TREE_TYPE (t2))) + { + candidates = candidates->next; + cand = NULL; + } + } + } + else if (TREE_CODE (t2) == REFERENCE_TYPE + && reference_compatible_p (t, TREE_TYPE (t2))) + cand = add_function_candidate (&candidates, f, s, arglist, + TYPE_BINFO (s), + TREE_PURPOSE (conversions), + LOOKUP_NORMAL); + + if (cand) + { + conversion *identity_conv; + /* Build a standard conversion sequence indicating the + binding from the reference type returned by the + function to the desired REFERENCE_TYPE. */ + identity_conv + = build_identity_conv (TREE_TYPE (TREE_TYPE + (TREE_TYPE (cand->fn))), + NULL_TREE); + cand->second_conv + = (direct_reference_binding + (reference_type, identity_conv)); + cand->second_conv->bad_p |= cand->convs[0]->bad_p; + } + } + conversions = TREE_CHAIN (conversions); + } + + candidates = splice_viable (candidates, pedantic, &any_viable_p); + /* If none of the conversion functions worked out, let our caller + know. */ + if (!any_viable_p) + return NULL; + + cand = tourney (candidates); + if (!cand) + return NULL; + + /* Now that we know that this is the function we're going to use fix + the dummy first argument. */ + cand->args = tree_cons (NULL_TREE, + build_this (expr), + TREE_CHAIN (cand->args)); + + /* Build a user-defined conversion sequence representing the + conversion. */ + conv = build_conv (ck_user, + TREE_TYPE (TREE_TYPE (cand->fn)), + build_identity_conv (TREE_TYPE (expr), expr)); + conv->cand = cand; + + /* Merge it with the standard conversion sequence from the + conversion function's return type to the desired type. */ + cand->second_conv = merge_conversion_sequences (conv, cand->second_conv); + + if (cand->viable == -1) + conv->bad_p = true; + + return cand->second_conv; +} + +/* A reference of the indicated TYPE is being bound directly to the + expression represented by the implicit conversion sequence CONV. + Return a conversion sequence for this binding. */ + +static conversion * +direct_reference_binding (tree type, conversion *conv) +{ + tree t; + + gcc_assert (TREE_CODE (type) == REFERENCE_TYPE); + gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE); + + t = TREE_TYPE (type); + + /* [over.ics.rank] + + When a parameter of reference type binds directly + (_dcl.init.ref_) to an argument expression, the implicit + conversion sequence is the identity conversion, unless the + argument expression has a type that is a derived class of the + parameter type, in which case the implicit conversion sequence is + a derived-to-base Conversion. + + If the parameter binds directly to the result of applying a + conversion function to the argument expression, the implicit + conversion sequence is a user-defined conversion sequence + (_over.ics.user_), with the second standard conversion sequence + either an identity conversion or, if the conversion function + returns an entity of a type that is a derived class of the + parameter type, a derived-to-base conversion. */ + if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type)) + { + /* Represent the derived-to-base conversion. */ + conv = build_conv (ck_base, t, conv); + /* We will actually be binding to the base-class subobject in + the derived class, so we mark this conversion appropriately. + That way, convert_like knows not to generate a temporary. */ + conv->need_temporary_p = false; + } + return build_conv (ck_ref_bind, type, conv); +} + +/* Returns the conversion path from type FROM to reference type TO for + purposes of reference binding. For lvalue binding, either pass a + reference type to FROM or an lvalue expression to EXPR. If the + reference will be bound to a temporary, NEED_TEMPORARY_P is set for + the conversion returned. If C_CAST_P is true, this + conversion is coming from a C-style cast. */ + +static conversion * +reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags) +{ + conversion *conv = NULL; + tree to = TREE_TYPE (rto); + tree from = rfrom; + bool related_p; + bool compatible_p; + cp_lvalue_kind lvalue_p = clk_none; + + if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr)) + { + expr = instantiate_type (to, expr, tf_none); + if (expr == error_mark_node) + return NULL; + from = TREE_TYPE (expr); + } + + if (TREE_CODE (from) == REFERENCE_TYPE) + { + /* Anything with reference type is an lvalue. */ + lvalue_p = clk_ordinary; + from = TREE_TYPE (from); + } + else if (expr) + lvalue_p = real_lvalue_p (expr); + + /* Figure out whether or not the types are reference-related and + reference compatible. We have do do this after stripping + references from FROM. */ + related_p = reference_related_p (to, from); + /* If this is a C cast, first convert to an appropriately qualified + type, so that we can later do a const_cast to the desired type. */ + if (related_p && c_cast_p + && !at_least_as_qualified_p (to, from)) + to = build_qualified_type (to, cp_type_quals (from)); + compatible_p = reference_compatible_p (to, from); + + if (lvalue_p && compatible_p) + { + /* [dcl.init.ref] + + If the initializer expression + + -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1" + is reference-compatible with "cv2 T2," + + the reference is bound directly to the initializer expression + lvalue. */ + conv = build_identity_conv (from, expr); + conv = direct_reference_binding (rto, conv); + if ((lvalue_p & clk_bitfield) != 0 + || ((lvalue_p & clk_packed) != 0 && !TYPE_PACKED (to))) + /* For the purposes of overload resolution, we ignore the fact + this expression is a bitfield or packed field. (In particular, + [over.ics.ref] says specifically that a function with a + non-const reference parameter is viable even if the + argument is a bitfield.) + + However, when we actually call the function we must create + a temporary to which to bind the reference. If the + reference is volatile, or isn't const, then we cannot make + a temporary, so we just issue an error when the conversion + actually occurs. */ + conv->need_temporary_p = true; + + return conv; + } + else if (CLASS_TYPE_P (from) && !(flags & LOOKUP_NO_CONVERSION)) + { + /* [dcl.init.ref] + + If the initializer expression + + -- has a class type (i.e., T2 is a class type) can be + implicitly converted to an lvalue of type "cv3 T3," where + "cv1 T1" is reference-compatible with "cv3 T3". (this + conversion is selected by enumerating the applicable + conversion functions (_over.match.ref_) and choosing the + best one through overload resolution. (_over.match_). + + the reference is bound to the lvalue result of the conversion + in the second case. */ + conv = convert_class_to_reference (to, from, expr); + if (conv) + return conv; + } + + /* From this point on, we conceptually need temporaries, even if we + elide them. Only the cases above are "direct bindings". */ + if (flags & LOOKUP_NO_TEMP_BIND) + return NULL; + + /* [over.ics.rank] + + When a parameter of reference type is not bound directly to an + argument expression, the conversion sequence is the one required + to convert the argument expression to the underlying type of the + reference according to _over.best.ics_. Conceptually, this + conversion sequence corresponds to copy-initializing a temporary + of the underlying type with the argument expression. Any + difference in top-level cv-qualification is subsumed by the + initialization itself and does not constitute a conversion. */ + + /* [dcl.init.ref] + + Otherwise, the reference shall be to a non-volatile const type. */ + if (!CP_TYPE_CONST_NON_VOLATILE_P (to)) + return NULL; + + /* [dcl.init.ref] + + If the initializer expression is an rvalue, with T2 a class type, + and "cv1 T1" is reference-compatible with "cv2 T2", the reference + is bound in one of the following ways: + + -- The reference is bound to the object represented by the rvalue + or to a sub-object within that object. + + -- ... + + We use the first alternative. The implicit conversion sequence + is supposed to be same as we would obtain by generating a + temporary. Fortunately, if the types are reference compatible, + then this is either an identity conversion or the derived-to-base + conversion, just as for direct binding. */ + if (CLASS_TYPE_P (from) && compatible_p) + { + conv = build_identity_conv (from, expr); + conv = direct_reference_binding (rto, conv); + if (!(flags & LOOKUP_CONSTRUCTOR_CALLABLE)) + conv->u.next->check_copy_constructor_p = true; + return conv; + } + + /* [dcl.init.ref] + + Otherwise, a temporary of type "cv1 T1" is created and + initialized from the initializer expression using the rules for a + non-reference copy initialization. If T1 is reference-related to + T2, cv1 must be the same cv-qualification as, or greater + cv-qualification than, cv2; otherwise, the program is ill-formed. */ + if (related_p && !at_least_as_qualified_p (to, from)) + return NULL; + + conv = implicit_conversion (to, from, expr, c_cast_p, + flags); + if (!conv) + return NULL; + + conv = build_conv (ck_ref_bind, rto, conv); + /* This reference binding, unlike those above, requires the + creation of a temporary. */ + conv->need_temporary_p = true; + + return conv; +} + +/* Returns the implicit conversion sequence (see [over.ics]) from type + FROM to type TO. The optional expression EXPR may affect the + conversion. FLAGS are the usual overloading flags. Only + LOOKUP_NO_CONVERSION is significant. If C_CAST_P is true, this + conversion is coming from a C-style cast. */ + +static conversion * +implicit_conversion (tree to, tree from, tree expr, bool c_cast_p, + int flags) +{ + conversion *conv; + + if (from == error_mark_node || to == error_mark_node + || expr == error_mark_node) + return NULL; + + /* APPLE LOCAL begin radar 4451818 */ + if (c_dialect_objc ()) + from = objc_non_volatilized_type (from); + /* APPLE LOCAL end radar 4451818 */ + + if (TREE_CODE (to) == REFERENCE_TYPE) + conv = reference_binding (to, from, expr, c_cast_p, flags); + else + conv = standard_conversion (to, from, expr, c_cast_p, flags); + + if (conv) + return conv; + + if (expr != NULL_TREE + && (IS_AGGR_TYPE (from) + || IS_AGGR_TYPE (to)) + && (flags & LOOKUP_NO_CONVERSION) == 0) + { + struct z_candidate *cand; + + cand = build_user_type_conversion_1 + (to, expr, LOOKUP_ONLYCONVERTING); + if (cand) + conv = cand->second_conv; + + /* We used to try to bind a reference to a temporary here, but that + is now handled by the recursive call to this function at the end + of reference_binding. */ + return conv; + } + + return NULL; +} + +/* Add a new entry to the list of candidates. Used by the add_*_candidate + functions. */ + +static struct z_candidate * +add_candidate (struct z_candidate **candidates, + tree fn, tree args, + size_t num_convs, conversion **convs, + tree access_path, tree conversion_path, + int viable) +{ + struct z_candidate *cand = (struct z_candidate *) + conversion_obstack_alloc (sizeof (struct z_candidate)); + + cand->fn = fn; + cand->args = args; + cand->convs = convs; + cand->num_convs = num_convs; + cand->access_path = access_path; + cand->conversion_path = conversion_path; + cand->viable = viable; + cand->next = *candidates; + *candidates = cand; + + return cand; +} + +/* Create an overload candidate for the function or method FN called with + the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on + to implicit_conversion. + + CTYPE, if non-NULL, is the type we want to pretend this function + comes from for purposes of overload resolution. */ + +static struct z_candidate * +add_function_candidate (struct z_candidate **candidates, + tree fn, tree ctype, tree arglist, + tree access_path, tree conversion_path, + int flags) +{ + tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn)); + int i, len; + conversion **convs; + tree parmnode, argnode; + tree orig_arglist; + int viable = 1; + + /* At this point we should not see any functions which haven't been + explicitly declared, except for friend functions which will have + been found using argument dependent lookup. */ + gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn)); + + /* The `this', `in_chrg' and VTT arguments to constructors are not + considered in overload resolution. */ + if (DECL_CONSTRUCTOR_P (fn)) + { + parmlist = skip_artificial_parms_for (fn, parmlist); + orig_arglist = arglist; + arglist = skip_artificial_parms_for (fn, arglist); + } + else + orig_arglist = arglist; + + len = list_length (arglist); + convs = alloc_conversions (len); + + /* 13.3.2 - Viable functions [over.match.viable] + First, to be a viable function, a candidate function shall have enough + parameters to agree in number with the arguments in the list. + + We need to check this first; otherwise, checking the ICSes might cause + us to produce an ill-formed template instantiation. */ + + parmnode = parmlist; + for (i = 0; i < len; ++i) + { + if (parmnode == NULL_TREE || parmnode == void_list_node) + break; + parmnode = TREE_CHAIN (parmnode); + } + + if (i < len && parmnode) + viable = 0; + + /* Make sure there are default args for the rest of the parms. */ + else if (!sufficient_parms_p (parmnode)) + viable = 0; + + if (! viable) + goto out; + + /* Second, for F to be a viable function, there shall exist for each + argument an implicit conversion sequence that converts that argument + to the corresponding parameter of F. */ + + parmnode = parmlist; + argnode = arglist; + + for (i = 0; i < len; ++i) + { + tree arg = TREE_VALUE (argnode); + tree argtype = lvalue_type (arg); + conversion *t; + int is_this; + + if (parmnode == void_list_node) + break; + + is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn) + && ! DECL_CONSTRUCTOR_P (fn)); + + if (parmnode) + { + tree parmtype = TREE_VALUE (parmnode); + + /* The type of the implicit object parameter ('this') for + overload resolution is not always the same as for the + function itself; conversion functions are considered to + be members of the class being converted, and functions + introduced by a using-declaration are considered to be + members of the class that uses them. + + Since build_over_call ignores the ICS for the `this' + parameter, we can just change the parm type. */ + if (ctype && is_this) + { + parmtype + = build_qualified_type (ctype, + TYPE_QUALS (TREE_TYPE (parmtype))); + parmtype = build_pointer_type (parmtype); + } + + t = implicit_conversion (parmtype, argtype, arg, + /*c_cast_p=*/false, flags); + } + else + { + t = build_identity_conv (argtype, arg); + t->ellipsis_p = true; + } + + if (t && is_this) + t->this_p = true; + + convs[i] = t; + if (! t) + { + viable = 0; + break; + } + + if (t->bad_p) + viable = -1; + + if (parmnode) + parmnode = TREE_CHAIN (parmnode); + argnode = TREE_CHAIN (argnode); + } + + out: + return add_candidate (candidates, fn, orig_arglist, len, convs, + access_path, conversion_path, viable); +} + +/* Create an overload candidate for the conversion function FN which will + be invoked for expression OBJ, producing a pointer-to-function which + will in turn be called with the argument list ARGLIST, and add it to + CANDIDATES. FLAGS is passed on to implicit_conversion. + + Actually, we don't really care about FN; we care about the type it + converts to. There may be multiple conversion functions that will + convert to that type, and we rely on build_user_type_conversion_1 to + choose the best one; so when we create our candidate, we record the type + instead of the function. */ + +static struct z_candidate * +add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj, + tree arglist, tree access_path, tree conversion_path) +{ + tree totype = TREE_TYPE (TREE_TYPE (fn)); + int i, len, viable, flags; + tree parmlist, parmnode, argnode; + conversion **convs; + + for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; ) + parmlist = TREE_TYPE (parmlist); + parmlist = TYPE_ARG_TYPES (parmlist); + + len = list_length (arglist) + 1; + convs = alloc_conversions (len); + parmnode = parmlist; + argnode = arglist; + viable = 1; + flags = LOOKUP_NORMAL; + + /* Don't bother looking up the same type twice. */ + if (*candidates && (*candidates)->fn == totype) + return NULL; + + for (i = 0; i < len; ++i) + { + tree arg = i == 0 ? obj : TREE_VALUE (argnode); + tree argtype = lvalue_type (arg); + conversion *t; + + if (i == 0) + t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false, + flags); + else if (parmnode == void_list_node) + break; + else if (parmnode) + t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg, + /*c_cast_p=*/false, flags); + else + { + t = build_identity_conv (argtype, arg); + t->ellipsis_p = true; + } + + convs[i] = t; + if (! t) + break; + + if (t->bad_p) + viable = -1; + + if (i == 0) + continue; + + if (parmnode) + parmnode = TREE_CHAIN (parmnode); + argnode = TREE_CHAIN (argnode); + } + + if (i < len) + viable = 0; + + if (!sufficient_parms_p (parmnode)) + viable = 0; + + return add_candidate (candidates, totype, arglist, len, convs, + access_path, conversion_path, viable); +} + +static void +build_builtin_candidate (struct z_candidate **candidates, tree fnname, + tree type1, tree type2, tree *args, tree *argtypes, + int flags) +{ + conversion *t; + conversion **convs; + size_t num_convs; + int viable = 1, i; + tree types[2]; + + types[0] = type1; + types[1] = type2; + + num_convs = args[2] ? 3 : (args[1] ? 2 : 1); + convs = alloc_conversions (num_convs); + + for (i = 0; i < 2; ++i) + { + if (! args[i]) + break; + + t = implicit_conversion (types[i], argtypes[i], args[i], + /*c_cast_p=*/false, flags); + if (! t) + { + viable = 0; + /* We need something for printing the candidate. */ + t = build_identity_conv (types[i], NULL_TREE); + } + else if (t->bad_p) + viable = 0; + convs[i] = t; + } + + /* For COND_EXPR we rearranged the arguments; undo that now. */ + if (args[2]) + { + convs[2] = convs[1]; + convs[1] = convs[0]; + t = implicit_conversion (boolean_type_node, argtypes[2], args[2], + /*c_cast_p=*/false, flags); + if (t) + convs[0] = t; + else + viable = 0; + } + + add_candidate (candidates, fnname, /*args=*/NULL_TREE, + num_convs, convs, + /*access_path=*/NULL_TREE, + /*conversion_path=*/NULL_TREE, + viable); +} + +static bool +is_complete (tree t) +{ + return COMPLETE_TYPE_P (complete_type (t)); +} + +/* Returns nonzero if TYPE is a promoted arithmetic type. */ + +static bool +promoted_arithmetic_type_p (tree type) +{ + /* [over.built] + + In this section, the term promoted integral type is used to refer + to those integral types which are preserved by integral promotion + (including e.g. int and long but excluding e.g. char). + Similarly, the term promoted arithmetic type refers to promoted + integral types plus floating types. */ + return ((INTEGRAL_TYPE_P (type) + && same_type_p (type_promotes_to (type), type)) + || TREE_CODE (type) == REAL_TYPE); +} + +/* Create any builtin operator overload candidates for the operator in + question given the converted operand types TYPE1 and TYPE2. The other + args are passed through from add_builtin_candidates to + build_builtin_candidate. + + TYPE1 and TYPE2 may not be permissible, and we must filter them. + If CODE is requires candidates operands of the same type of the kind + of which TYPE1 and TYPE2 are, we add both candidates + CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */ + +static void +add_builtin_candidate (struct z_candidate **candidates, enum tree_code code, + enum tree_code code2, tree fnname, tree type1, + tree type2, tree *args, tree *argtypes, int flags) +{ + switch (code) + { + case POSTINCREMENT_EXPR: + case POSTDECREMENT_EXPR: + args[1] = integer_zero_node; + type2 = integer_type_node; + break; + default: + break; + } + + switch (code) + { + +/* 4 For every pair T, VQ), where T is an arithmetic or enumeration type, + and VQ is either volatile or empty, there exist candidate operator + functions of the form + VQ T& operator++(VQ T&); + T operator++(VQ T&, int); + 5 For every pair T, VQ), where T is an enumeration type or an arithmetic + type other than bool, and VQ is either volatile or empty, there exist + candidate operator functions of the form + VQ T& operator--(VQ T&); + T operator--(VQ T&, int); + 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified + complete object type, and VQ is either volatile or empty, there exist + candidate operator functions of the form + T*VQ& operator++(T*VQ&); + T*VQ& operator--(T*VQ&); + T* operator++(T*VQ&, int); + T* operator--(T*VQ&, int); */ + + case POSTDECREMENT_EXPR: + case PREDECREMENT_EXPR: + if (TREE_CODE (type1) == BOOLEAN_TYPE) + return; + case POSTINCREMENT_EXPR: + case PREINCREMENT_EXPR: + if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1)) + { + type1 = build_reference_type (type1); + break; + } + return; + +/* 7 For every cv-qualified or cv-unqualified complete object type T, there + exist candidate operator functions of the form + + T& operator*(T*); + + 8 For every function type T, there exist candidate operator functions of + the form + T& operator*(T*); */ + + case INDIRECT_REF: + if (TREE_CODE (type1) == POINTER_TYPE + && (TYPE_PTROB_P (type1) + || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)) + break; + return; + +/* 9 For every type T, there exist candidate operator functions of the form + T* operator+(T*); + + 10For every promoted arithmetic type T, there exist candidate operator + functions of the form + T operator+(T); + T operator-(T); */ + + case UNARY_PLUS_EXPR: /* unary + */ + if (TREE_CODE (type1) == POINTER_TYPE) + break; + case NEGATE_EXPR: + if (ARITHMETIC_TYPE_P (type1)) + break; + return; + +/* 11For every promoted integral type T, there exist candidate operator + functions of the form + T operator~(T); */ + + case BIT_NOT_EXPR: + if (INTEGRAL_TYPE_P (type1)) + break; + return; + +/* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1 + is the same type as C2 or is a derived class of C2, T is a complete + object type or a function type, and CV1 and CV2 are cv-qualifier-seqs, + there exist candidate operator functions of the form + CV12 T& operator->*(CV1 C1*, CV2 T C2::*); + where CV12 is the union of CV1 and CV2. */ + + case MEMBER_REF: + if (TREE_CODE (type1) == POINTER_TYPE + && TYPE_PTR_TO_MEMBER_P (type2)) + { + tree c1 = TREE_TYPE (type1); + tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2); + + if (IS_AGGR_TYPE (c1) && DERIVED_FROM_P (c2, c1) + && (TYPE_PTRMEMFUNC_P (type2) + || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2)))) + break; + } + return; + +/* 13For every pair of promoted arithmetic types L and R, there exist can- + didate operator functions of the form + LR operator*(L, R); + LR operator/(L, R); + LR operator+(L, R); + LR operator-(L, R); + bool operator<(L, R); + bool operator>(L, R); + bool operator<=(L, R); + bool operator>=(L, R); + bool operator==(L, R); + bool operator!=(L, R); + where LR is the result of the usual arithmetic conversions between + types L and R. + + 14For every pair of types T and I, where T is a cv-qualified or cv- + unqualified complete object type and I is a promoted integral type, + there exist candidate operator functions of the form + T* operator+(T*, I); + T& operator[](T*, I); + T* operator-(T*, I); + T* operator+(I, T*); + T& operator[](I, T*); + + 15For every T, where T is a pointer to complete object type, there exist + candidate operator functions of the form112) + ptrdiff_t operator-(T, T); + + 16For every pointer or enumeration type T, there exist candidate operator + functions of the form + bool operator<(T, T); + bool operator>(T, T); + bool operator<=(T, T); + bool operator>=(T, T); + bool operator==(T, T); + bool operator!=(T, T); + + 17For every pointer to member type T, there exist candidate operator + functions of the form + bool operator==(T, T); + bool operator!=(T, T); */ + + case MINUS_EXPR: + if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2)) + break; + if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2)) + { + type2 = ptrdiff_type_node; + break; + } + case MULT_EXPR: + case TRUNC_DIV_EXPR: + if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2)) + break; + return; + + case EQ_EXPR: + case NE_EXPR: + if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2)) + || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))) + break; + if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1])) + { + type2 = type1; + break; + } + if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0])) + { + type1 = type2; + break; + } + /* Fall through. */ + case LT_EXPR: + case GT_EXPR: + case LE_EXPR: + case GE_EXPR: + case MAX_EXPR: + case MIN_EXPR: + if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2)) + break; + if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2)) + break; + if (TREE_CODE (type1) == ENUMERAL_TYPE + && TREE_CODE (type2) == ENUMERAL_TYPE) + break; + if (TYPE_PTR_P (type1) + && null_ptr_cst_p (args[1]) + && !uses_template_parms (type1)) + { + type2 = type1; + break; + } + if (null_ptr_cst_p (args[0]) + && TYPE_PTR_P (type2) + && !uses_template_parms (type2)) + { + type1 = type2; + break; + } + return; + + case PLUS_EXPR: + if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2)) + break; + case ARRAY_REF: + if (INTEGRAL_TYPE_P (type1) && TYPE_PTROB_P (type2)) + { + type1 = ptrdiff_type_node; + break; + } + if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2)) + { + type2 = ptrdiff_type_node; + break; + } + return; + +/* 18For every pair of promoted integral types L and R, there exist candi- + date operator functions of the form + LR operator%(L, R); + LR operator&(L, R); + LR operator^(L, R); + LR operator|(L, R); + L operator<<(L, R); + L operator>>(L, R); + where LR is the result of the usual arithmetic conversions between + types L and R. */ + + case TRUNC_MOD_EXPR: + case BIT_AND_EXPR: + case BIT_IOR_EXPR: + case BIT_XOR_EXPR: + case LSHIFT_EXPR: + case RSHIFT_EXPR: + if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2)) + break; + return; + +/* 19For every triple L, VQ, R), where L is an arithmetic or enumeration + type, VQ is either volatile or empty, and R is a promoted arithmetic + type, there exist candidate operator functions of the form + VQ L& operator=(VQ L&, R); + VQ L& operator*=(VQ L&, R); + VQ L& operator/=(VQ L&, R); + VQ L& operator+=(VQ L&, R); + VQ L& operator-=(VQ L&, R); + + 20For every pair T, VQ), where T is any type and VQ is either volatile + or empty, there exist candidate operator functions of the form + T*VQ& operator=(T*VQ&, T*); + + 21For every pair T, VQ), where T is a pointer to member type and VQ is + either volatile or empty, there exist candidate operator functions of + the form + VQ T& operator=(VQ T&, T); + + 22For every triple T, VQ, I), where T is a cv-qualified or cv- + unqualified complete object type, VQ is either volatile or empty, and + I is a promoted integral type, there exist candidate operator func- + tions of the form + T*VQ& operator+=(T*VQ&, I); + T*VQ& operator-=(T*VQ&, I); + + 23For every triple L, VQ, R), where L is an integral or enumeration + type, VQ is either volatile or empty, and R is a promoted integral + type, there exist candidate operator functions of the form + + VQ L& operator%=(VQ L&, R); + VQ L& operator<<=(VQ L&, R); + VQ L& operator>>=(VQ L&, R); + VQ L& operator&=(VQ L&, R); + VQ L& operator^=(VQ L&, R); + VQ L& operator|=(VQ L&, R); */ + + case MODIFY_EXPR: + switch (code2) + { + case PLUS_EXPR: + case MINUS_EXPR: + if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2)) + { + type2 = ptrdiff_type_node; + break; + } + case MULT_EXPR: + case TRUNC_DIV_EXPR: + if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2)) + break; + return; + + case TRUNC_MOD_EXPR: + case BIT_AND_EXPR: + case BIT_IOR_EXPR: + case BIT_XOR_EXPR: + case LSHIFT_EXPR: + case RSHIFT_EXPR: + if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2)) + break; + return; + + case NOP_EXPR: + if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2)) + break; + if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2)) + || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2)) + || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)) + || ((TYPE_PTRMEMFUNC_P (type1) + || TREE_CODE (type1) == POINTER_TYPE) + && null_ptr_cst_p (args[1]))) + { + type2 = type1; + break; + } + return; + + default: + gcc_unreachable (); + } + type1 = build_reference_type (type1); + break; + + case COND_EXPR: + /* [over.built] + + For every pair of promoted arithmetic types L and R, there + exist candidate operator functions of the form + + LR operator?(bool, L, R); + + where LR is the result of the usual arithmetic conversions + between types L and R. + + For every type T, where T is a pointer or pointer-to-member + type, there exist candidate operator functions of the form T + operator?(bool, T, T); */ + + if (promoted_arithmetic_type_p (type1) + && promoted_arithmetic_type_p (type2)) + /* That's OK. */ + break; + + /* Otherwise, the types should be pointers. */ + if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1)) + || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2))) + return; + + /* We don't check that the two types are the same; the logic + below will actually create two candidates; one in which both + parameter types are TYPE1, and one in which both parameter + types are TYPE2. */ + break; + + default: + gcc_unreachable (); + } + + /* If we're dealing with two pointer types or two enumeral types, + we need candidates for both of them. */ + if (type2 && !same_type_p (type1, type2) + && TREE_CODE (type1) == TREE_CODE (type2) + && (TREE_CODE (type1) == REFERENCE_TYPE + || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2)) + || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)) + || TYPE_PTRMEMFUNC_P (type1) + || IS_AGGR_TYPE (type1) + || TREE_CODE (type1) == ENUMERAL_TYPE)) + { + build_builtin_candidate + (candidates, fnname, type1, type1, args, argtypes, flags); + build_builtin_candidate + (candidates, fnname, type2, type2, args, argtypes, flags); + return; + } + + build_builtin_candidate + (candidates, fnname, type1, type2, args, argtypes, flags); +} + +tree +type_decays_to (tree type) +{ + if (TREE_CODE (type) == ARRAY_TYPE) + return build_pointer_type (TREE_TYPE (type)); + if (TREE_CODE (type) == FUNCTION_TYPE) + return build_pointer_type (type); + return type; +} + +/* There are three conditions of builtin candidates: + + 1) bool-taking candidates. These are the same regardless of the input. + 2) pointer-pair taking candidates. These are generated for each type + one of the input types converts to. + 3) arithmetic candidates. According to the standard, we should generate + all of these, but I'm trying not to... + + Here we generate a superset of the possible candidates for this particular + case. That is a subset of the full set the standard defines, plus some + other cases which the standard disallows. add_builtin_candidate will + filter out the invalid set. */ + +static void +add_builtin_candidates (struct z_candidate **candidates, enum tree_code code, + enum tree_code code2, tree fnname, tree *args, + int flags) +{ + int ref1, i; + int enum_p = 0; + tree type, argtypes[3]; + /* TYPES[i] is the set of possible builtin-operator parameter types + we will consider for the Ith argument. These are represented as + a TREE_LIST; the TREE_VALUE of each node is the potential + parameter type. */ + tree types[2]; + + for (i = 0; i < 3; ++i) + { + if (args[i]) + argtypes[i] = lvalue_type (args[i]); + else + argtypes[i] = NULL_TREE; + } + + switch (code) + { +/* 4 For every pair T, VQ), where T is an arithmetic or enumeration type, + and VQ is either volatile or empty, there exist candidate operator + functions of the form + VQ T& operator++(VQ T&); */ + + case POSTINCREMENT_EXPR: + case PREINCREMENT_EXPR: + case POSTDECREMENT_EXPR: + case PREDECREMENT_EXPR: + case MODIFY_EXPR: + ref1 = 1; + break; + +/* 24There also exist candidate operator functions of the form + bool operator!(bool); + bool operator&&(bool, bool); + bool operator||(bool, bool); */ + + case TRUTH_NOT_EXPR: + build_builtin_candidate + (candidates, fnname, boolean_type_node, + NULL_TREE, args, argtypes, flags); + return; + + case TRUTH_ORIF_EXPR: + case TRUTH_ANDIF_EXPR: + build_builtin_candidate + (candidates, fnname, boolean_type_node, + boolean_type_node, args, argtypes, flags); + return; + + case ADDR_EXPR: + case COMPOUND_EXPR: + case COMPONENT_REF: + return; + + case COND_EXPR: + case EQ_EXPR: + case NE_EXPR: + case LT_EXPR: + case LE_EXPR: + case GT_EXPR: + case GE_EXPR: + enum_p = 1; + /* Fall through. */ + + default: + ref1 = 0; + } + + types[0] = types[1] = NULL_TREE; + + for (i = 0; i < 2; ++i) + { + if (! args[i]) + ; + else if (IS_AGGR_TYPE (argtypes[i])) + { + tree convs; + + if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR) + return; + + convs = lookup_conversions (argtypes[i]); + + if (code == COND_EXPR) + { + if (real_lvalue_p (args[i])) + types[i] = tree_cons + (NULL_TREE, build_reference_type (argtypes[i]), types[i]); + + types[i] = tree_cons + (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]); + } + + else if (! convs) + return; + + for (; convs; convs = TREE_CHAIN (convs)) + { + type = TREE_TYPE (TREE_TYPE (OVL_CURRENT (TREE_VALUE (convs)))); + + if (i == 0 && ref1 + && (TREE_CODE (type) != REFERENCE_TYPE + || CP_TYPE_CONST_P (TREE_TYPE (type)))) + continue; + + if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE) + types[i] = tree_cons (NULL_TREE, type, types[i]); + + type = non_reference (type); + if (i != 0 || ! ref1) + { + type = TYPE_MAIN_VARIANT (type_decays_to (type)); + if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE) + types[i] = tree_cons (NULL_TREE, type, types[i]); + if (INTEGRAL_TYPE_P (type)) + type = type_promotes_to (type); + } + + if (! value_member (type, types[i])) + types[i] = tree_cons (NULL_TREE, type, types[i]); + } + } + else + { + if (code == COND_EXPR && real_lvalue_p (args[i])) + types[i] = tree_cons + (NULL_TREE, build_reference_type (argtypes[i]), types[i]); + type = non_reference (argtypes[i]); + if (i != 0 || ! ref1) + { + type = TYPE_MAIN_VARIANT (type_decays_to (type)); + if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE) + types[i] = tree_cons (NULL_TREE, type, types[i]); + if (INTEGRAL_TYPE_P (type)) + type = type_promotes_to (type); + } + types[i] = tree_cons (NULL_TREE, type, types[i]); + } + } + + /* Run through the possible parameter types of both arguments, + creating candidates with those parameter types. */ + for (; types[0]; types[0] = TREE_CHAIN (types[0])) + { + if (types[1]) + for (type = types[1]; type; type = TREE_CHAIN (type)) + add_builtin_candidate + (candidates, code, code2, fnname, TREE_VALUE (types[0]), + TREE_VALUE (type), args, argtypes, flags); + else + add_builtin_candidate + (candidates, code, code2, fnname, TREE_VALUE (types[0]), + NULL_TREE, args, argtypes, flags); + } +} + + +/* If TMPL can be successfully instantiated as indicated by + EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES. + + TMPL is the template. EXPLICIT_TARGS are any explicit template + arguments. ARGLIST is the arguments provided at the call-site. + The RETURN_TYPE is the desired type for conversion operators. If + OBJ is NULL_TREE, FLAGS and CTYPE are as for add_function_candidate. + If an OBJ is supplied, FLAGS and CTYPE are ignored, and OBJ is as for + add_conv_candidate. */ + +static struct z_candidate* +add_template_candidate_real (struct z_candidate **candidates, tree tmpl, + tree ctype, tree explicit_targs, tree arglist, + tree return_type, tree access_path, + tree conversion_path, int flags, tree obj, + unification_kind_t strict) +{ + int ntparms = DECL_NTPARMS (tmpl); + tree targs = make_tree_vec (ntparms); + tree args_without_in_chrg = arglist; + struct z_candidate *cand; + int i; + tree fn; + + /* We don't do deduction on the in-charge parameter, the VTT + parameter or 'this'. */ + if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl)) + args_without_in_chrg = TREE_CHAIN (args_without_in_chrg); + + if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl) + || DECL_BASE_CONSTRUCTOR_P (tmpl)) + && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl))) + args_without_in_chrg = TREE_CHAIN (args_without_in_chrg); + + i = fn_type_unification (tmpl, explicit_targs, targs, + args_without_in_chrg, + return_type, strict, flags); + + if (i != 0) + return NULL; + + fn = instantiate_template (tmpl, targs, tf_none); + if (fn == error_mark_node) + return NULL; + + /* In [class.copy]: + + A member function template is never instantiated to perform the + copy of a class object to an object of its class type. + + It's a little unclear what this means; the standard explicitly + does allow a template to be used to copy a class. For example, + in: + + struct A { + A(A&); + template <class T> A(const T&); + }; + const A f (); + void g () { A a (f ()); } + + the member template will be used to make the copy. The section + quoted above appears in the paragraph that forbids constructors + whose only parameter is (a possibly cv-qualified variant of) the + class type, and a logical interpretation is that the intent was + to forbid the instantiation of member templates which would then + have that form. */ + if (DECL_CONSTRUCTOR_P (fn) && list_length (arglist) == 2) + { + tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn); + if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)), + ctype)) + return NULL; + } + + if (obj != NULL_TREE) + /* Aha, this is a conversion function. */ + cand = add_conv_candidate (candidates, fn, obj, access_path, + conversion_path, arglist); + else + cand = add_function_candidate (candidates, fn, ctype, + arglist, access_path, + conversion_path, flags); + if (DECL_TI_TEMPLATE (fn) != tmpl) + /* This situation can occur if a member template of a template + class is specialized. Then, instantiate_template might return + an instantiation of the specialization, in which case the + DECL_TI_TEMPLATE field will point at the original + specialization. For example: + + template <class T> struct S { template <class U> void f(U); + template <> void f(int) {}; }; + S<double> sd; + sd.f(3); + + Here, TMPL will be template <class U> S<double>::f(U). + And, instantiate template will give us the specialization + template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field + for this will point at template <class T> template <> S<T>::f(int), + so that we can find the definition. For the purposes of + overload resolution, however, we want the original TMPL. */ + cand->template_decl = tree_cons (tmpl, targs, NULL_TREE); + else + cand->template_decl = DECL_TEMPLATE_INFO (fn); + + return cand; +} + + +static struct z_candidate * +add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype, + tree explicit_targs, tree arglist, tree return_type, + tree access_path, tree conversion_path, int flags, + unification_kind_t strict) +{ + return + add_template_candidate_real (candidates, tmpl, ctype, + explicit_targs, arglist, return_type, + access_path, conversion_path, + flags, NULL_TREE, strict); +} + + +static struct z_candidate * +add_template_conv_candidate (struct z_candidate **candidates, tree tmpl, + tree obj, tree arglist, tree return_type, + tree access_path, tree conversion_path) +{ + return + add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE, + arglist, return_type, access_path, + conversion_path, 0, obj, DEDUCE_CONV); +} + +/* The CANDS are the set of candidates that were considered for + overload resolution. Return the set of viable candidates. If none + of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P + is true if a candidate should be considered viable only if it is + strictly viable. */ + +static struct z_candidate* +splice_viable (struct z_candidate *cands, + bool strict_p, + bool *any_viable_p) +{ + struct z_candidate *viable; + struct z_candidate **last_viable; + struct z_candidate **cand; + + viable = NULL; + last_viable = &viable; + *any_viable_p = false; + + cand = &cands; + while (*cand) + { + struct z_candidate *c = *cand; + if (strict_p ? c->viable == 1 : c->viable) + { + *last_viable = c; + *cand = c->next; + c->next = NULL; + last_viable = &c->next; + *any_viable_p = true; + } + else + cand = &c->next; + } + + return viable ? viable : cands; +} + +static bool +any_strictly_viable (struct z_candidate *cands) +{ + for (; cands; cands = cands->next) + if (cands->viable == 1) + return true; + return false; +} + +/* OBJ is being used in an expression like "OBJ.f (...)". In other + words, it is about to become the "this" pointer for a member + function call. Take the address of the object. */ + +static tree +build_this (tree obj) +{ + /* In a template, we are only concerned about the type of the + expression, so we can take a shortcut. */ + if (processing_template_decl) + return build_address (obj); + + return build_unary_op (ADDR_EXPR, obj, 0); +} + +/* Returns true iff functions are equivalent. Equivalent functions are + not '==' only if one is a function-local extern function or if + both are extern "C". */ + +static inline int +equal_functions (tree fn1, tree fn2) +{ + if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2) + || DECL_EXTERN_C_FUNCTION_P (fn1)) + return decls_match (fn1, fn2); + return fn1 == fn2; +} + +/* Print information about one overload candidate CANDIDATE. MSGSTR + is the text to print before the candidate itself. + + NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected + to have been run through gettext by the caller. This wart makes + life simpler in print_z_candidates and for the translators. */ + +static void +print_z_candidate (const char *msgstr, struct z_candidate *candidate) +{ + if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE) + { + if (candidate->num_convs == 3) + inform ("%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn, + candidate->convs[0]->type, + candidate->convs[1]->type, + candidate->convs[2]->type); + else if (candidate->num_convs == 2) + inform ("%s %D(%T, %T) <built-in>", msgstr, candidate->fn, + candidate->convs[0]->type, + candidate->convs[1]->type); + else + inform ("%s %D(%T) <built-in>", msgstr, candidate->fn, + candidate->convs[0]->type); + } + else if (TYPE_P (candidate->fn)) + inform ("%s %T <conversion>", msgstr, candidate->fn); + else if (candidate->viable == -1) + inform ("%s %+#D <near match>", msgstr, candidate->fn); + else + inform ("%s %+#D", msgstr, candidate->fn); +} + +static void +print_z_candidates (struct z_candidate *candidates) +{ + const char *str; + struct z_candidate *cand1; + struct z_candidate **cand2; + + /* There may be duplicates in the set of candidates. We put off + checking this condition as long as possible, since we have no way + to eliminate duplicates from a set of functions in less than n^2 + time. Now we are about to emit an error message, so it is more + permissible to go slowly. */ + for (cand1 = candidates; cand1; cand1 = cand1->next) + { + tree fn = cand1->fn; + /* Skip builtin candidates and conversion functions. */ + if (TREE_CODE (fn) != FUNCTION_DECL) + continue; + cand2 = &cand1->next; + while (*cand2) + { + if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL + && equal_functions (fn, (*cand2)->fn)) + *cand2 = (*cand2)->next; + else + cand2 = &(*cand2)->next; + } + } + + if (!candidates) + return; + + str = _("candidates are:"); + print_z_candidate (str, candidates); + if (candidates->next) + { + /* Indent successive candidates by the width of the translation + of the above string. */ + size_t len = gcc_gettext_width (str) + 1; + char *spaces = (char *) alloca (len); + memset (spaces, ' ', len-1); + spaces[len - 1] = '\0'; + + candidates = candidates->next; + do + { + print_z_candidate (spaces, candidates); + candidates = candidates->next; + } + while (candidates); + } +} + +/* USER_SEQ is a user-defined conversion sequence, beginning with a + USER_CONV. STD_SEQ is the standard conversion sequence applied to + the result of the conversion function to convert it to the final + desired type. Merge the two sequences into a single sequence, + and return the merged sequence. */ + +static conversion * +merge_conversion_sequences (conversion *user_seq, conversion *std_seq) +{ + conversion **t; + + gcc_assert (user_seq->kind == ck_user); + + /* Find the end of the second conversion sequence. */ + t = &(std_seq); + while ((*t)->kind != ck_identity) + t = &((*t)->u.next); + + /* Replace the identity conversion with the user conversion + sequence. */ + *t = user_seq; + + /* The entire sequence is a user-conversion sequence. */ + std_seq->user_conv_p = true; + + return std_seq; +} + +/* Returns the best overload candidate to perform the requested + conversion. This function is used for three the overloading situations + described in [over.match.copy], [over.match.conv], and [over.match.ref]. + If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as + per [dcl.init.ref], so we ignore temporary bindings. */ + +static struct z_candidate * +build_user_type_conversion_1 (tree totype, tree expr, int flags) +{ + struct z_candidate *candidates, *cand; + tree fromtype = TREE_TYPE (expr); + tree ctors = NULL_TREE; + tree conv_fns = NULL_TREE; + conversion *conv = NULL; + tree args = NULL_TREE; + bool any_viable_p; + + /* We represent conversion within a hierarchy using RVALUE_CONV and + BASE_CONV, as specified by [over.best.ics]; these become plain + constructor calls, as specified in [dcl.init]. */ + gcc_assert (!IS_AGGR_TYPE (fromtype) || !IS_AGGR_TYPE (totype) + || !DERIVED_FROM_P (totype, fromtype)); + + if (IS_AGGR_TYPE (totype)) + ctors = lookup_fnfields (totype, complete_ctor_identifier, 0); + + if (IS_AGGR_TYPE (fromtype)) + conv_fns = lookup_conversions (fromtype); + + candidates = 0; + flags |= LOOKUP_NO_CONVERSION; + + if (ctors) + { + tree t; + + ctors = BASELINK_FUNCTIONS (ctors); + + t = build_int_cst (build_pointer_type (totype), 0); + args = build_tree_list (NULL_TREE, expr); + /* We should never try to call the abstract or base constructor + from here. */ + gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors)) + && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors))); + args = tree_cons (NULL_TREE, t, args); + } + for (; ctors; ctors = OVL_NEXT (ctors)) + { + tree ctor = OVL_CURRENT (ctors); + if (DECL_NONCONVERTING_P (ctor)) + continue; + + if (TREE_CODE (ctor) == TEMPLATE_DECL) + cand = add_template_candidate (&candidates, ctor, totype, + NULL_TREE, args, NULL_TREE, + TYPE_BINFO (totype), + TYPE_BINFO (totype), + flags, + DEDUCE_CALL); + else + cand = add_function_candidate (&candidates, ctor, totype, + args, TYPE_BINFO (totype), + TYPE_BINFO (totype), + flags); + + if (cand) + cand->second_conv = build_identity_conv (totype, NULL_TREE); + } + + if (conv_fns) + args = build_tree_list (NULL_TREE, build_this (expr)); + + for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns)) + { + tree fns; + tree conversion_path = TREE_PURPOSE (conv_fns); + int convflags = LOOKUP_NO_CONVERSION; + + /* If we are called to convert to a reference type, we are trying to + find an lvalue binding, so don't even consider temporaries. If + we don't find an lvalue binding, the caller will try again to + look for a temporary binding. */ + if (TREE_CODE (totype) == REFERENCE_TYPE) + convflags |= LOOKUP_NO_TEMP_BIND; + + for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns)) + { + tree fn = OVL_CURRENT (fns); + + /* [over.match.funcs] For conversion functions, the function + is considered to be a member of the class of the implicit + object argument for the purpose of defining the type of + the implicit object parameter. + + So we pass fromtype as CTYPE to add_*_candidate. */ + + if (TREE_CODE (fn) == TEMPLATE_DECL) + cand = add_template_candidate (&candidates, fn, fromtype, + NULL_TREE, + args, totype, + TYPE_BINFO (fromtype), + conversion_path, + flags, + DEDUCE_CONV); + else + cand = add_function_candidate (&candidates, fn, fromtype, + args, + TYPE_BINFO (fromtype), + conversion_path, + flags); + + if (cand) + { + conversion *ics + = implicit_conversion (totype, + TREE_TYPE (TREE_TYPE (cand->fn)), + 0, + /*c_cast_p=*/false, convflags); + + cand->second_conv = ics; + + if (!ics) + cand->viable = 0; + else if (candidates->viable == 1 && ics->bad_p) + cand->viable = -1; + } + } + } + + candidates = splice_viable (candidates, pedantic, &any_viable_p); + if (!any_viable_p) + return NULL; + + cand = tourney (candidates); + if (cand == 0) + { + if (flags & LOOKUP_COMPLAIN) + { + error ("conversion from %qT to %qT is ambiguous", + fromtype, totype); + print_z_candidates (candidates); + } + + cand = candidates; /* any one will do */ + cand->second_conv = build_ambiguous_conv (totype, expr); + cand->second_conv->user_conv_p = true; + if (!any_strictly_viable (candidates)) + cand->second_conv->bad_p = true; + /* If there are viable candidates, don't set ICS_BAD_FLAG; an + ambiguous conversion is no worse than another user-defined + conversion. */ + + return cand; + } + + /* Build the user conversion sequence. */ + conv = build_conv + (ck_user, + (DECL_CONSTRUCTOR_P (cand->fn) + ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))), + build_identity_conv (TREE_TYPE (expr), expr)); + conv->cand = cand; + + /* Combine it with the second conversion sequence. */ + cand->second_conv = merge_conversion_sequences (conv, + cand->second_conv); + + if (cand->viable == -1) + cand->second_conv->bad_p = true; + + return cand; +} + +tree +build_user_type_conversion (tree totype, tree expr, int flags) +{ + struct z_candidate *cand + = build_user_type_conversion_1 (totype, expr, flags); + + if (cand) + { + if (cand->second_conv->kind == ck_ambig) + return error_mark_node; + expr = convert_like (cand->second_conv, expr); + return convert_from_reference (expr); + } + return NULL_TREE; +} + +/* Do any initial processing on the arguments to a function call. */ + +static tree +resolve_args (tree args) +{ + tree t; + for (t = args; t; t = TREE_CHAIN (t)) + { + tree arg = TREE_VALUE (t); + + if (error_operand_p (arg)) + return error_mark_node; + else if (VOID_TYPE_P (TREE_TYPE (arg))) + { + error ("invalid use of void expression"); + return error_mark_node; + } + else if (invalid_nonstatic_memfn_p (arg)) + return error_mark_node; + } + return args; +} + +/* Perform overload resolution on FN, which is called with the ARGS. + + Return the candidate function selected by overload resolution, or + NULL if the event that overload resolution failed. In the case + that overload resolution fails, *CANDIDATES will be the set of + candidates considered, and ANY_VIABLE_P will be set to true or + false to indicate whether or not any of the candidates were + viable. + + The ARGS should already have gone through RESOLVE_ARGS before this + function is called. */ + +static struct z_candidate * +perform_overload_resolution (tree fn, + tree args, + struct z_candidate **candidates, + bool *any_viable_p) +{ + struct z_candidate *cand; + tree explicit_targs = NULL_TREE; + int template_only = 0; + + *candidates = NULL; + *any_viable_p = true; + + /* Check FN and ARGS. */ + gcc_assert (TREE_CODE (fn) == FUNCTION_DECL + || TREE_CODE (fn) == TEMPLATE_DECL + || TREE_CODE (fn) == OVERLOAD + || TREE_CODE (fn) == TEMPLATE_ID_EXPR); + gcc_assert (!args || TREE_CODE (args) == TREE_LIST); + + if (TREE_CODE (fn) == TEMPLATE_ID_EXPR) + { + explicit_targs = TREE_OPERAND (fn, 1); + fn = TREE_OPERAND (fn, 0); + template_only = 1; + } + + /* Add the various candidate functions. */ + add_candidates (fn, args, explicit_targs, template_only, + /*conversion_path=*/NULL_TREE, + /*access_path=*/NULL_TREE, + LOOKUP_NORMAL, + candidates); + + *candidates = splice_viable (*candidates, pedantic, any_viable_p); + if (!*any_viable_p) + return NULL; + + cand = tourney (*candidates); + return cand; +} + +/* Return an expression for a call to FN (a namespace-scope function, + or a static member function) with the ARGS. */ + +tree +build_new_function_call (tree fn, tree args, bool koenig_p) +{ + struct z_candidate *candidates, *cand; + bool any_viable_p; + void *p; + tree result; + + args = resolve_args (args); + if (args == error_mark_node) + return error_mark_node; + + /* If this function was found without using argument dependent + lookup, then we want to ignore any undeclared friend + functions. */ + if (!koenig_p) + { + tree orig_fn = fn; + + fn = remove_hidden_names (fn); + if (!fn) + { + error ("no matching function for call to %<%D(%A)%>", + DECL_NAME (OVL_CURRENT (orig_fn)), args); + return error_mark_node; + } + } + + /* Get the high-water mark for the CONVERSION_OBSTACK. */ + p = conversion_obstack_alloc (0); + + cand = perform_overload_resolution (fn, args, &candidates, &any_viable_p); + + if (!cand) + { + if (!any_viable_p && candidates && ! candidates->next) + return build_function_call (candidates->fn, args); + if (TREE_CODE (fn) == TEMPLATE_ID_EXPR) + fn = TREE_OPERAND (fn, 0); + if (!any_viable_p) + error ("no matching function for call to %<%D(%A)%>", + DECL_NAME (OVL_CURRENT (fn)), args); + else + error ("call of overloaded %<%D(%A)%> is ambiguous", + DECL_NAME (OVL_CURRENT (fn)), args); + if (candidates) + print_z_candidates (candidates); + result = error_mark_node; + } + else + result = build_over_call (cand, LOOKUP_NORMAL); + + /* Free all the conversions we allocated. */ + obstack_free (&conversion_obstack, p); + + return result; +} + +/* Build a call to a global operator new. FNNAME is the name of the + operator (either "operator new" or "operator new[]") and ARGS are + the arguments provided. *SIZE points to the total number of bytes + required by the allocation, and is updated if that is changed here. + *COOKIE_SIZE is non-NULL if a cookie should be used. If this + function determines that no cookie should be used, after all, + *COOKIE_SIZE is set to NULL_TREE. If FN is non-NULL, it will be + set, upon return, to the allocation function called. */ + +tree +build_operator_new_call (tree fnname, tree args, + tree *size, tree *cookie_size, + tree *fn) +{ + tree fns; + struct z_candidate *candidates; + struct z_candidate *cand; + bool any_viable_p; + + if (fn) + *fn = NULL_TREE; + args = tree_cons (NULL_TREE, *size, args); + args = resolve_args (args); + if (args == error_mark_node) + return args; + + /* Based on: + + [expr.new] + + If this lookup fails to find the name, or if the allocated type + is not a class type, the allocation function's name is looked + up in the global scope. + + we disregard block-scope declarations of "operator new". */ + fns = lookup_function_nonclass (fnname, args, /*block_p=*/false); + + /* Figure out what function is being called. */ + cand = perform_overload_resolution (fns, args, &candidates, &any_viable_p); + + /* If no suitable function could be found, issue an error message + and give up. */ + if (!cand) + { + if (!any_viable_p) + error ("no matching function for call to %<%D(%A)%>", + DECL_NAME (OVL_CURRENT (fns)), args); + else + error ("call of overloaded %<%D(%A)%> is ambiguous", + DECL_NAME (OVL_CURRENT (fns)), args); + if (candidates) + print_z_candidates (candidates); + return error_mark_node; + } + + /* If a cookie is required, add some extra space. Whether + or not a cookie is required cannot be determined until + after we know which function was called. */ + if (*cookie_size) + { + bool use_cookie = true; + if (!abi_version_at_least (2)) + { + tree placement = TREE_CHAIN (args); + /* In G++ 3.2, the check was implemented incorrectly; it + looked at the placement expression, rather than the + type of the function. */ + if (placement && !TREE_CHAIN (placement) + && same_type_p (TREE_TYPE (TREE_VALUE (placement)), + ptr_type_node)) + use_cookie = false; + } + else + { + tree arg_types; + + arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn)); + /* Skip the size_t parameter. */ + arg_types = TREE_CHAIN (arg_types); + /* Check the remaining parameters (if any). */ + if (arg_types + && TREE_CHAIN (arg_types) == void_list_node + && same_type_p (TREE_VALUE (arg_types), + ptr_type_node)) + use_cookie = false; + } + /* If we need a cookie, adjust the number of bytes allocated. */ + if (use_cookie) + { + /* Update the total size. */ + *size = size_binop (PLUS_EXPR, *size, *cookie_size); + /* Update the argument list to reflect the adjusted size. */ + TREE_VALUE (args) = *size; + } + else + *cookie_size = NULL_TREE; + } + + /* Tell our caller which function we decided to call. */ + if (fn) + *fn = cand->fn; + + /* Build the CALL_EXPR. */ + return build_over_call (cand, LOOKUP_NORMAL); +} + +static tree +build_object_call (tree obj, tree args) +{ + struct z_candidate *candidates = 0, *cand; + tree fns, convs, mem_args = NULL_TREE; + tree type = TREE_TYPE (obj); + bool any_viable_p; + tree result = NULL_TREE; + void *p; + + if (TYPE_PTRMEMFUNC_P (type)) + { + /* It's no good looking for an overloaded operator() on a + pointer-to-member-function. */ + error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj); + return error_mark_node; + } + + if (TYPE_BINFO (type)) + { + fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1); + if (fns == error_mark_node) + return error_mark_node; + } + else + fns = NULL_TREE; + + args = resolve_args (args); + + if (args == error_mark_node) + return error_mark_node; + + /* Get the high-water mark for the CONVERSION_OBSTACK. */ + p = conversion_obstack_alloc (0); + + if (fns) + { + tree base = BINFO_TYPE (BASELINK_BINFO (fns)); + mem_args = tree_cons (NULL_TREE, build_this (obj), args); + + for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns)) + { + tree fn = OVL_CURRENT (fns); + if (TREE_CODE (fn) == TEMPLATE_DECL) + add_template_candidate (&candidates, fn, base, NULL_TREE, + mem_args, NULL_TREE, + TYPE_BINFO (type), + TYPE_BINFO (type), + LOOKUP_NORMAL, DEDUCE_CALL); + else + add_function_candidate + (&candidates, fn, base, mem_args, TYPE_BINFO (type), + TYPE_BINFO (type), LOOKUP_NORMAL); + } + } + + convs = lookup_conversions (type); + + for (; convs; convs = TREE_CHAIN (convs)) + { + tree fns = TREE_VALUE (convs); + tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns))); + + if ((TREE_CODE (totype) == POINTER_TYPE + && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE) + || (TREE_CODE (totype) == REFERENCE_TYPE + && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE) + || (TREE_CODE (totype) == REFERENCE_TYPE + && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE + && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE)) + for (; fns; fns = OVL_NEXT (fns)) + { + tree fn = OVL_CURRENT (fns); + if (TREE_CODE (fn) == TEMPLATE_DECL) + add_template_conv_candidate + (&candidates, fn, obj, args, totype, + /*access_path=*/NULL_TREE, + /*conversion_path=*/NULL_TREE); + else + add_conv_candidate (&candidates, fn, obj, args, + /*conversion_path=*/NULL_TREE, + /*access_path=*/NULL_TREE); + } + } + + candidates = splice_viable (candidates, pedantic, &any_viable_p); + if (!any_viable_p) + { + error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj), args); + print_z_candidates (candidates); + result = error_mark_node; + } + else + { + cand = tourney (candidates); + if (cand == 0) + { + error ("call of %<(%T) (%A)%> is ambiguous", TREE_TYPE (obj), args); + print_z_candidates (candidates); + result = error_mark_node; + } + /* Since cand->fn will be a type, not a function, for a conversion + function, we must be careful not to unconditionally look at + DECL_NAME here. */ + else if (TREE_CODE (cand->fn) == FUNCTION_DECL + && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR) + result = build_over_call (cand, LOOKUP_NORMAL); + else + { + obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1); + obj = convert_from_reference (obj); + result = build_function_call (obj, args); + } + } + + /* Free all the conversions we allocated. */ + obstack_free (&conversion_obstack, p); + + return result; +} + +static void +op_error (enum tree_code code, enum tree_code code2, + tree arg1, tree arg2, tree arg3, const char *problem) +{ + const char *opname; + + if (code == MODIFY_EXPR) + opname = assignment_operator_name_info[code2].name; + else + opname = operator_name_info[code].name; + + switch (code) + { + case COND_EXPR: + error ("%s for ternary %<operator?:%> in %<%E ? %E : %E%>", + problem, arg1, arg2, arg3); + break; + + case POSTINCREMENT_EXPR: + case POSTDECREMENT_EXPR: + error ("%s for %<operator%s%> in %<%E%s%>", problem, opname, arg1, opname); + break; + + case ARRAY_REF: + error ("%s for %<operator[]%> in %<%E[%E]%>", problem, arg1, arg2); + break; + + case REALPART_EXPR: + case IMAGPART_EXPR: + error ("%s for %qs in %<%s %E%>", problem, opname, opname, arg1); + break; + + default: + if (arg2) + error ("%s for %<operator%s%> in %<%E %s %E%>", + problem, opname, arg1, opname, arg2); + else + error ("%s for %<operator%s%> in %<%s%E%>", + problem, opname, opname, arg1); + break; + } +} + +/* Return the implicit conversion sequence that could be used to + convert E1 to E2 in [expr.cond]. */ + +static conversion * +conditional_conversion (tree e1, tree e2) +{ + tree t1 = non_reference (TREE_TYPE (e1)); + tree t2 = non_reference (TREE_TYPE (e2)); + conversion *conv; + bool good_base; + + /* [expr.cond] + + If E2 is an lvalue: E1 can be converted to match E2 if E1 can be + implicitly converted (clause _conv_) to the type "reference to + T2", subject to the constraint that in the conversion the + reference must bind directly (_dcl.init.ref_) to E1. */ + if (real_lvalue_p (e2)) + { + conv = implicit_conversion (build_reference_type (t2), + t1, + e1, + /*c_cast_p=*/false, + LOOKUP_NO_TEMP_BIND); + if (conv) + return conv; + } + + /* [expr.cond] + + If E1 and E2 have class type, and the underlying class types are + the same or one is a base class of the other: E1 can be converted + to match E2 if the class of T2 is the same type as, or a base + class of, the class of T1, and the cv-qualification of T2 is the + same cv-qualification as, or a greater cv-qualification than, the + cv-qualification of T1. If the conversion is applied, E1 is + changed to an rvalue of type T2 that still refers to the original + source class object (or the appropriate subobject thereof). */ + if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2) + && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2))) + { + if (good_base && at_least_as_qualified_p (t2, t1)) + { + conv = build_identity_conv (t1, e1); + if (!same_type_p (TYPE_MAIN_VARIANT (t1), + TYPE_MAIN_VARIANT (t2))) + conv = build_conv (ck_base, t2, conv); + else + conv = build_conv (ck_rvalue, t2, conv); + return conv; + } + else + return NULL; + } + else + /* [expr.cond] + + Otherwise: E1 can be converted to match E2 if E1 can be implicitly + converted to the type that expression E2 would have if E2 were + converted to an rvalue (or the type it has, if E2 is an rvalue). */ + return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false, + LOOKUP_NORMAL); +} + +/* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three + arguments to the conditional expression. */ + +tree +build_conditional_expr (tree arg1, tree arg2, tree arg3) +{ + tree arg2_type; + tree arg3_type; + tree result = NULL_TREE; + tree result_type = NULL_TREE; + bool lvalue_p = true; + struct z_candidate *candidates = 0; + struct z_candidate *cand; + void *p; + + /* As a G++ extension, the second argument to the conditional can be + omitted. (So that `a ? : c' is roughly equivalent to `a ? a : + c'.) If the second operand is omitted, make sure it is + calculated only once. */ + if (!arg2) + { + if (pedantic) + pedwarn ("ISO C++ forbids omitting the middle term of a ?: expression"); + + /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */ + if (real_lvalue_p (arg1)) + arg2 = arg1 = stabilize_reference (arg1); + else + arg2 = arg1 = save_expr (arg1); + } + + /* [expr.cond] + + The first expr ession is implicitly converted to bool (clause + _conv_). */ + arg1 = perform_implicit_conversion (boolean_type_node, arg1); + + /* If something has already gone wrong, just pass that fact up the + tree. */ + if (error_operand_p (arg1) + || error_operand_p (arg2) + || error_operand_p (arg3)) + return error_mark_node; + + /* [expr.cond] + + If either the second or the third operand has type (possibly + cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_), + array-to-pointer (_conv.array_), and function-to-pointer + (_conv.func_) standard conversions are performed on the second + and third operands. */ + arg2_type = unlowered_expr_type (arg2); + arg3_type = unlowered_expr_type (arg3); + if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type)) + { + /* Do the conversions. We don't these for `void' type arguments + since it can't have any effect and since decay_conversion + does not handle that case gracefully. */ + if (!VOID_TYPE_P (arg2_type)) + arg2 = decay_conversion (arg2); + if (!VOID_TYPE_P (arg3_type)) + arg3 = decay_conversion (arg3); + arg2_type = TREE_TYPE (arg2); + arg3_type = TREE_TYPE (arg3); + + /* [expr.cond] + + One of the following shall hold: + + --The second or the third operand (but not both) is a + throw-expression (_except.throw_); the result is of the + type of the other and is an rvalue. + + --Both the second and the third operands have type void; the + result is of type void and is an rvalue. + + We must avoid calling force_rvalue for expressions of type + "void" because it will complain that their value is being + used. */ + if (TREE_CODE (arg2) == THROW_EXPR + && TREE_CODE (arg3) != THROW_EXPR) + { + if (!VOID_TYPE_P (arg3_type)) + arg3 = force_rvalue (arg3); + arg3_type = TREE_TYPE (arg3); + result_type = arg3_type; + } + else if (TREE_CODE (arg2) != THROW_EXPR + && TREE_CODE (arg3) == THROW_EXPR) + { + if (!VOID_TYPE_P (arg2_type)) + arg2 = force_rvalue (arg2); + arg2_type = TREE_TYPE (arg2); + result_type = arg2_type; + } + else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type)) + result_type = void_type_node; + else + { + error ("%qE has type %<void%> and is not a throw-expression", + VOID_TYPE_P (arg2_type) ? arg2 : arg3); + return error_mark_node; + } + + lvalue_p = false; + goto valid_operands; + } + /* [expr.cond] + + Otherwise, if the second and third operand have different types, + and either has (possibly cv-qualified) class type, an attempt is + made to convert each of those operands to the type of the other. */ + else if (!same_type_p (arg2_type, arg3_type) + && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type))) + { + conversion *conv2; + conversion *conv3; + + /* Get the high-water mark for the CONVERSION_OBSTACK. */ + p = conversion_obstack_alloc (0); + + conv2 = conditional_conversion (arg2, arg3); + conv3 = conditional_conversion (arg3, arg2); + + /* [expr.cond] + + If both can be converted, or one can be converted but the + conversion is ambiguous, the program is ill-formed. If + neither can be converted, the operands are left unchanged and + further checking is performed as described below. If exactly + one conversion is possible, that conversion is applied to the + chosen operand and the converted operand is used in place of + the original operand for the remainder of this section. */ + if ((conv2 && !conv2->bad_p + && conv3 && !conv3->bad_p) + || (conv2 && conv2->kind == ck_ambig) + || (conv3 && conv3->kind == ck_ambig)) + { + error ("operands to ?: have different types %qT and %qT", + arg2_type, arg3_type); + result = error_mark_node; + } + else if (conv2 && (!conv2->bad_p || !conv3)) + { + arg2 = convert_like (conv2, arg2); + arg2 = convert_from_reference (arg2); + arg2_type = TREE_TYPE (arg2); + /* Even if CONV2 is a valid conversion, the result of the + conversion may be invalid. For example, if ARG3 has type + "volatile X", and X does not have a copy constructor + accepting a "volatile X&", then even if ARG2 can be + converted to X, the conversion will fail. */ + if (error_operand_p (arg2)) + result = error_mark_node; + } + else if (conv3 && (!conv3->bad_p || !conv2)) + { + arg3 = convert_like (conv3, arg3); + arg3 = convert_from_reference (arg3); + arg3_type = TREE_TYPE (arg3); + if (error_operand_p (arg3)) + result = error_mark_node; + } + + /* Free all the conversions we allocated. */ + obstack_free (&conversion_obstack, p); + + if (result) + return result; + + /* If, after the conversion, both operands have class type, + treat the cv-qualification of both operands as if it were the + union of the cv-qualification of the operands. + + The standard is not clear about what to do in this + circumstance. For example, if the first operand has type + "const X" and the second operand has a user-defined + conversion to "volatile X", what is the type of the second + operand after this step? Making it be "const X" (matching + the first operand) seems wrong, as that discards the + qualification without actually performing a copy. Leaving it + as "volatile X" seems wrong as that will result in the + conditional expression failing altogether, even though, + according to this step, the one operand could be converted to + the type of the other. */ + if ((conv2 || conv3) + && CLASS_TYPE_P (arg2_type) + && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type)) + arg2_type = arg3_type = + cp_build_qualified_type (arg2_type, + TYPE_QUALS (arg2_type) + | TYPE_QUALS (arg3_type)); + } + + /* [expr.cond] + + If the second and third operands are lvalues and have the same + type, the result is of that type and is an lvalue. */ + if (real_lvalue_p (arg2) + && real_lvalue_p (arg3) + && same_type_p (arg2_type, arg3_type)) + { + result_type = arg2_type; + goto valid_operands; + } + + /* [expr.cond] + + Otherwise, the result is an rvalue. If the second and third + operand do not have the same type, and either has (possibly + cv-qualified) class type, overload resolution is used to + determine the conversions (if any) to be applied to the operands + (_over.match.oper_, _over.built_). */ + lvalue_p = false; + if (!same_type_p (arg2_type, arg3_type) + && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type))) + { + tree args[3]; + conversion *conv; + bool any_viable_p; + + /* Rearrange the arguments so that add_builtin_candidate only has + to know about two args. In build_builtin_candidates, the + arguments are unscrambled. */ + args[0] = arg2; + args[1] = arg3; + args[2] = arg1; + add_builtin_candidates (&candidates, + COND_EXPR, + NOP_EXPR, + ansi_opname (COND_EXPR), + args, + LOOKUP_NORMAL); + + /* [expr.cond] + + If the overload resolution fails, the program is + ill-formed. */ + candidates = splice_viable (candidates, pedantic, &any_viable_p); + if (!any_viable_p) + { + op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match"); + print_z_candidates (candidates); + return error_mark_node; + } + cand = tourney (candidates); + if (!cand) + { + op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match"); + print_z_candidates (candidates); + return error_mark_node; + } + + /* [expr.cond] + + Otherwise, the conversions thus determined are applied, and + the converted operands are used in place of the original + operands for the remainder of this section. */ + conv = cand->convs[0]; + arg1 = convert_like (conv, arg1); + conv = cand->convs[1]; + arg2 = convert_like (conv, arg2); + conv = cand->convs[2]; + arg3 = convert_like (conv, arg3); + } + + /* [expr.cond] + + Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_), + and function-to-pointer (_conv.func_) standard conversions are + performed on the second and third operands. + + We need to force the lvalue-to-rvalue conversion here for class types, + so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues + that isn't wrapped with a TARGET_EXPR plays havoc with exception + regions. */ + + arg2 = force_rvalue (arg2); + if (!CLASS_TYPE_P (arg2_type)) + arg2_type = TREE_TYPE (arg2); + + arg3 = force_rvalue (arg3); + if (!CLASS_TYPE_P (arg2_type)) + arg3_type = TREE_TYPE (arg3); + + if (arg2 == error_mark_node || arg3 == error_mark_node) + return error_mark_node; + + /* [expr.cond] + + After those conversions, one of the following shall hold: + + --The second and third operands have the same type; the result is of + that type. */ + if (same_type_p (arg2_type, arg3_type)) + result_type = arg2_type; + /* [expr.cond] + + --The second and third operands have arithmetic or enumeration + type; the usual arithmetic conversions are performed to bring + them to a common type, and the result is of that type. */ + else if ((ARITHMETIC_TYPE_P (arg2_type) + || TREE_CODE (arg2_type) == ENUMERAL_TYPE) + && (ARITHMETIC_TYPE_P (arg3_type) + || TREE_CODE (arg3_type) == ENUMERAL_TYPE)) + { + /* In this case, there is always a common type. */ + result_type = type_after_usual_arithmetic_conversions (arg2_type, + arg3_type); + + if (TREE_CODE (arg2_type) == ENUMERAL_TYPE + && TREE_CODE (arg3_type) == ENUMERAL_TYPE) + warning (0, "enumeral mismatch in conditional expression: %qT vs %qT", + arg2_type, arg3_type); + else if (extra_warnings + && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE + && !same_type_p (arg3_type, type_promotes_to (arg2_type))) + || (TREE_CODE (arg3_type) == ENUMERAL_TYPE + && !same_type_p (arg2_type, type_promotes_to (arg3_type))))) + warning (0, "enumeral and non-enumeral type in conditional expression"); + + arg2 = perform_implicit_conversion (result_type, arg2); + arg3 = perform_implicit_conversion (result_type, arg3); + } + /* [expr.cond] + + --The second and third operands have pointer type, or one has + pointer type and the other is a null pointer constant; pointer + conversions (_conv.ptr_) and qualification conversions + (_conv.qual_) are performed to bring them to their composite + pointer type (_expr.rel_). The result is of the composite + pointer type. + + --The second and third operands have pointer to member type, or + one has pointer to member type and the other is a null pointer + constant; pointer to member conversions (_conv.mem_) and + qualification conversions (_conv.qual_) are performed to bring + them to a common type, whose cv-qualification shall match the + cv-qualification of either the second or the third operand. + The result is of the common type. */ + else if ((null_ptr_cst_p (arg2) + /* APPLE LOCAL begin blocks 6040305 (co) */ + && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type) + || TREE_CODE (arg3_type) == BLOCK_POINTER_TYPE)) + /* APPLE LOCAL end blocks 6040305 (co) */ + || (null_ptr_cst_p (arg3) + /* APPLE LOCAL begin blocks 6040305 (co) */ + && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type) + || TREE_CODE (arg2_type) == BLOCK_POINTER_TYPE)) + || ((TYPE_PTR_P (arg2_type) + || TREE_CODE (arg2_type) == BLOCK_POINTER_TYPE) + && (TYPE_PTR_P (arg3_type) + || TREE_CODE (arg3_type) == BLOCK_POINTER_TYPE)) + /* APPLE LOCAL end blocks 6040305 (co) */ + || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type)) + || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type))) + { + result_type = composite_pointer_type (arg2_type, arg3_type, arg2, + arg3, "conditional expression"); + if (result_type == error_mark_node) + return error_mark_node; + arg2 = perform_implicit_conversion (result_type, arg2); + arg3 = perform_implicit_conversion (result_type, arg3); + } + + if (!result_type) + { + error ("operands to ?: have different types %qT and %qT", + arg2_type, arg3_type); + return error_mark_node; + } + + valid_operands: + result = fold_if_not_in_template (build3 (COND_EXPR, result_type, arg1, + arg2, arg3)); + /* We can't use result_type below, as fold might have returned a + throw_expr. */ + + if (!lvalue_p) + { + /* Expand both sides into the same slot, hopefully the target of + the ?: expression. We used to check for TARGET_EXPRs here, + but now we sometimes wrap them in NOP_EXPRs so the test would + fail. */ + if (CLASS_TYPE_P (TREE_TYPE (result))) + result = get_target_expr (result); + /* If this expression is an rvalue, but might be mistaken for an + lvalue, we must add a NON_LVALUE_EXPR. */ + result = rvalue (result); + } + + return result; +} + +/* OPERAND is an operand to an expression. Perform necessary steps + required before using it. If OPERAND is NULL_TREE, NULL_TREE is + returned. */ + +static tree +prep_operand (tree operand) +{ + if (operand) + { + if (CLASS_TYPE_P (TREE_TYPE (operand)) + && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand))) + /* Make sure the template type is instantiated now. */ + instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand))); + } + + return operand; +} + +/* Add each of the viable functions in FNS (a FUNCTION_DECL or + OVERLOAD) to the CANDIDATES, returning an updated list of + CANDIDATES. The ARGS are the arguments provided to the call, + without any implicit object parameter. The EXPLICIT_TARGS are + explicit template arguments provided. TEMPLATE_ONLY is true if + only template functions should be considered. CONVERSION_PATH, + ACCESS_PATH, and FLAGS are as for add_function_candidate. */ + +static void +add_candidates (tree fns, tree args, + tree explicit_targs, bool template_only, + tree conversion_path, tree access_path, + int flags, + struct z_candidate **candidates) +{ + tree ctype; + tree non_static_args; + + ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE; + /* Delay creating the implicit this parameter until it is needed. */ + non_static_args = NULL_TREE; + + while (fns) + { + tree fn; + tree fn_args; + + fn = OVL_CURRENT (fns); + /* Figure out which set of arguments to use. */ + if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)) + { + /* If this function is a non-static member, prepend the implicit + object parameter. */ + if (!non_static_args) + non_static_args = tree_cons (NULL_TREE, + build_this (TREE_VALUE (args)), + TREE_CHAIN (args)); + fn_args = non_static_args; + } + else + /* Otherwise, just use the list of arguments provided. */ + fn_args = args; + + if (TREE_CODE (fn) == TEMPLATE_DECL) + add_template_candidate (candidates, + fn, + ctype, + explicit_targs, + fn_args, + NULL_TREE, + access_path, + conversion_path, + flags, + DEDUCE_CALL); + else if (!template_only) + add_function_candidate (candidates, + fn, + ctype, + fn_args, + access_path, + conversion_path, + flags); + fns = OVL_NEXT (fns); + } +} + +tree +build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3, + bool *overloaded_p) +{ + struct z_candidate *candidates = 0, *cand; + tree arglist, fnname; + tree args[3]; + tree result = NULL_TREE; + bool result_valid_p = false; + enum tree_code code2 = NOP_EXPR; + conversion *conv; + void *p; + bool strict_p; + bool any_viable_p; + + if (error_operand_p (arg1) + || error_operand_p (arg2) + || error_operand_p (arg3)) + return error_mark_node; + + if (code == MODIFY_EXPR) + { + code2 = TREE_CODE (arg3); + arg3 = NULL_TREE; + fnname = ansi_assopname (code2); + } + else + fnname = ansi_opname (code); + + arg1 = prep_operand (arg1); + + switch (code) + { + case NEW_EXPR: + case VEC_NEW_EXPR: + case VEC_DELETE_EXPR: + case DELETE_EXPR: + /* Use build_op_new_call and build_op_delete_call instead. */ + gcc_unreachable (); + + case CALL_EXPR: + return build_object_call (arg1, arg2); + + default: + break; + } + + arg2 = prep_operand (arg2); + arg3 = prep_operand (arg3); + + if (code == COND_EXPR) + { + if (arg2 == NULL_TREE + || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE + || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE + || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2)) + && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3)))) + goto builtin; + } + else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1)) + && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2)))) + goto builtin; + + if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR) + arg2 = integer_zero_node; + + arglist = NULL_TREE; + if (arg3) + arglist = tree_cons (NULL_TREE, arg3, arglist); + if (arg2) + arglist = tree_cons (NULL_TREE, arg2, arglist); + arglist = tree_cons (NULL_TREE, arg1, arglist); + + /* Get the high-water mark for the CONVERSION_OBSTACK. */ + p = conversion_obstack_alloc (0); + + /* Add namespace-scope operators to the list of functions to + consider. */ + add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true), + arglist, NULL_TREE, false, NULL_TREE, NULL_TREE, + flags, &candidates); + /* Add class-member operators to the candidate set. */ + if (CLASS_TYPE_P (TREE_TYPE (arg1))) + { + tree fns; + + fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1); + if (fns == error_mark_node) + { + result = error_mark_node; + goto user_defined_result_ready; + } + if (fns) + add_candidates (BASELINK_FUNCTIONS (fns), arglist, + NULL_TREE, false, + BASELINK_BINFO (fns), + TYPE_BINFO (TREE_TYPE (arg1)), + flags, &candidates); + } + + /* Rearrange the arguments for ?: so that add_builtin_candidate only has + to know about two args; a builtin candidate will always have a first + parameter of type bool. We'll handle that in + build_builtin_candidate. */ + if (code == COND_EXPR) + { + args[0] = arg2; + args[1] = arg3; + args[2] = arg1; + } + else + { + args[0] = arg1; + args[1] = arg2; + args[2] = NULL_TREE; + } + + add_builtin_candidates (&candidates, code, code2, fnname, args, flags); + + switch (code) + { + case COMPOUND_EXPR: + case ADDR_EXPR: + /* For these, the built-in candidates set is empty + [over.match.oper]/3. We don't want non-strict matches + because exact matches are always possible with built-in + operators. The built-in candidate set for COMPONENT_REF + would be empty too, but since there are no such built-in + operators, we accept non-strict matches for them. */ + strict_p = true; + break; + + default: + strict_p = pedantic; + break; + } + + candidates = splice_viable (candidates, strict_p, &any_viable_p); + if (!any_viable_p) + { + switch (code) + { + case POSTINCREMENT_EXPR: + case POSTDECREMENT_EXPR: + /* Look for an `operator++ (int)'. If they didn't have + one, then we fall back to the old way of doing things. */ + if (flags & LOOKUP_COMPLAIN) + pedwarn ("no %<%D(int)%> declared for postfix %qs, " + "trying prefix operator instead", + fnname, + operator_name_info[code].name); + if (code == POSTINCREMENT_EXPR) + code = PREINCREMENT_EXPR; + else + code = PREDECREMENT_EXPR; + result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE, + overloaded_p); + break; + + /* The caller will deal with these. */ + case ADDR_EXPR: + case COMPOUND_EXPR: + case COMPONENT_REF: + result = NULL_TREE; + result_valid_p = true; + break; + + default: + if (flags & LOOKUP_COMPLAIN) + { + op_error (code, code2, arg1, arg2, arg3, "no match"); + print_z_candidates (candidates); + } + result = error_mark_node; + break; + } + } + else + { + cand = tourney (candidates); + if (cand == 0) + { + if (flags & LOOKUP_COMPLAIN) + { + op_error (code, code2, arg1, arg2, arg3, "ambiguous overload"); + print_z_candidates (candidates); + } + result = error_mark_node; + } + else if (TREE_CODE (cand->fn) == FUNCTION_DECL) + { + if (overloaded_p) + *overloaded_p = true; + + result = build_over_call (cand, LOOKUP_NORMAL); + } + else + { + /* Give any warnings we noticed during overload resolution. */ + if (cand->warnings) + { + struct candidate_warning *w; + for (w = cand->warnings; w; w = w->next) + joust (cand, w->loser, 1); + } + + /* Check for comparison of different enum types. */ + switch (code) + { + case GT_EXPR: + case LT_EXPR: + case GE_EXPR: + case LE_EXPR: + case EQ_EXPR: + case NE_EXPR: + if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE + && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE + && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1)) + != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))) + { + warning (0, "comparison between %q#T and %q#T", + TREE_TYPE (arg1), TREE_TYPE (arg2)); + } + break; + default: + break; + } + + /* We need to strip any leading REF_BIND so that bitfields + don't cause errors. This should not remove any important + conversions, because builtins don't apply to class + objects directly. */ + conv = cand->convs[0]; + if (conv->kind == ck_ref_bind) + conv = conv->u.next; + arg1 = convert_like (conv, arg1); + if (arg2) + { + conv = cand->convs[1]; + if (conv->kind == ck_ref_bind) + conv = conv->u.next; + arg2 = convert_like (conv, arg2); + } + if (arg3) + { + conv = cand->convs[2]; + if (conv->kind == ck_ref_bind) + conv = conv->u.next; + arg3 = convert_like (conv, arg3); + } + } + } + + user_defined_result_ready: + + /* Free all the conversions we allocated. */ + obstack_free (&conversion_obstack, p); + + if (result || result_valid_p) + return result; + + builtin: + switch (code) + { + case MODIFY_EXPR: + return build_modify_expr (arg1, code2, arg2); + + case INDIRECT_REF: + return build_indirect_ref (arg1, "unary *"); + + case PLUS_EXPR: + case MINUS_EXPR: + case MULT_EXPR: + case TRUNC_DIV_EXPR: + case GT_EXPR: + case LT_EXPR: + case GE_EXPR: + case LE_EXPR: + case EQ_EXPR: + case NE_EXPR: + case MAX_EXPR: + case MIN_EXPR: + case LSHIFT_EXPR: + case RSHIFT_EXPR: + case TRUNC_MOD_EXPR: + case BIT_AND_EXPR: + case BIT_IOR_EXPR: + case BIT_XOR_EXPR: + case TRUTH_ANDIF_EXPR: + case TRUTH_ORIF_EXPR: + return cp_build_binary_op (code, arg1, arg2); + + case UNARY_PLUS_EXPR: + case NEGATE_EXPR: + case BIT_NOT_EXPR: + case TRUTH_NOT_EXPR: + case PREINCREMENT_EXPR: + case POSTINCREMENT_EXPR: + case PREDECREMENT_EXPR: + case POSTDECREMENT_EXPR: + case REALPART_EXPR: + case IMAGPART_EXPR: + return build_unary_op (code, arg1, candidates != 0); + + case ARRAY_REF: + return build_array_ref (arg1, arg2); + + case COND_EXPR: + return build_conditional_expr (arg1, arg2, arg3); + + case MEMBER_REF: + return build_m_component_ref (build_indirect_ref (arg1, NULL), arg2); + + /* The caller will deal with these. */ + case ADDR_EXPR: + case COMPONENT_REF: + case COMPOUND_EXPR: + return NULL_TREE; + + default: + gcc_unreachable (); + } + return NULL_TREE; +} + +/* Build a call to operator delete. This has to be handled very specially, + because the restrictions on what signatures match are different from all + other call instances. For a normal delete, only a delete taking (void *) + or (void *, size_t) is accepted. For a placement delete, only an exact + match with the placement new is accepted. + + CODE is either DELETE_EXPR or VEC_DELETE_EXPR. + ADDR is the pointer to be deleted. + SIZE is the size of the memory block to be deleted. + GLOBAL_P is true if the delete-expression should not consider + class-specific delete operators. + PLACEMENT is the corresponding placement new call, or NULL_TREE. + + If this call to "operator delete" is being generated as part to + deallocate memory allocated via a new-expression (as per [expr.new] + which requires that if the initialization throws an exception then + we call a deallocation function), then ALLOC_FN is the allocation + function. */ + +tree +build_op_delete_call (enum tree_code code, tree addr, tree size, + bool global_p, tree placement, + tree alloc_fn) +{ + tree fn = NULL_TREE; + tree fns, fnname, argtypes, args, type; + int pass; + + if (addr == error_mark_node) + return error_mark_node; + + type = strip_array_types (TREE_TYPE (TREE_TYPE (addr))); + + fnname = ansi_opname (code); + + if (CLASS_TYPE_P (type) + && COMPLETE_TYPE_P (complete_type (type)) + && !global_p) + /* In [class.free] + + If the result of the lookup is ambiguous or inaccessible, or if + the lookup selects a placement deallocation function, the + program is ill-formed. + + Therefore, we ask lookup_fnfields to complain about ambiguity. */ + { + fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1); + if (fns == error_mark_node) + return error_mark_node; + } + else + fns = NULL_TREE; + + if (fns == NULL_TREE) + fns = lookup_name_nonclass (fnname); + + if (placement) + { + /* Get the parameter types for the allocation function that is + being called. */ + gcc_assert (alloc_fn != NULL_TREE); + argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn))); + /* Also the second argument. */ + args = TREE_CHAIN (TREE_OPERAND (placement, 1)); + } + else + { + /* First try it without the size argument. */ + argtypes = void_list_node; + args = NULL_TREE; + } + + /* Strip const and volatile from addr. */ + addr = cp_convert (ptr_type_node, addr); + + /* We make two tries at finding a matching `operator delete'. On + the first pass, we look for a one-operator (or placement) + operator delete. If we're not doing placement delete, then on + the second pass we look for a two-argument delete. */ + for (pass = 0; pass < (placement ? 1 : 2); ++pass) + { + /* Go through the `operator delete' functions looking for one + with a matching type. */ + for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns; + fn; + fn = OVL_NEXT (fn)) + { + tree t; + + /* The first argument must be "void *". */ + t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn))); + if (!same_type_p (TREE_VALUE (t), ptr_type_node)) + continue; + t = TREE_CHAIN (t); + /* On the first pass, check the rest of the arguments. */ + if (pass == 0) + { + tree a = argtypes; + while (a && t) + { + if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t))) + break; + a = TREE_CHAIN (a); + t = TREE_CHAIN (t); + } + if (!a && !t) + break; + } + /* On the second pass, look for a function with exactly two + arguments: "void *" and "size_t". */ + else if (pass == 1 + /* For "operator delete(void *, ...)" there will be + no second argument, but we will not get an exact + match above. */ + && t + && same_type_p (TREE_VALUE (t), sizetype) + && TREE_CHAIN (t) == void_list_node) + break; + } + + /* If we found a match, we're done. */ + if (fn) + break; + } + + /* If we have a matching function, call it. */ + if (fn) + { + /* Make sure we have the actual function, and not an + OVERLOAD. */ + fn = OVL_CURRENT (fn); + + /* If the FN is a member function, make sure that it is + accessible. */ + if (DECL_CLASS_SCOPE_P (fn)) + perform_or_defer_access_check (TYPE_BINFO (type), fn, fn); + + if (pass == 0) + args = tree_cons (NULL_TREE, addr, args); + else + args = tree_cons (NULL_TREE, addr, + build_tree_list (NULL_TREE, size)); + + if (placement) + { + /* The placement args might not be suitable for overload + resolution at this point, so build the call directly. */ + mark_used (fn); + return build_cxx_call (fn, args); + } + else + return build_function_call (fn, args); + } + + /* [expr.new] + + If no unambiguous matching deallocation function can be found, + propagating the exception does not cause the object's memory to + be freed. */ + if (alloc_fn) + { + if (!placement) + warning (0, "no corresponding deallocation function for `%D'", + alloc_fn); + return NULL_TREE; + } + + error ("no suitable %<operator %s%> for %qT", + operator_name_info[(int)code].name, type); + return error_mark_node; +} + +/* If the current scope isn't allowed to access DECL along + BASETYPE_PATH, give an error. The most derived class in + BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is + the declaration to use in the error diagnostic. */ + +bool +enforce_access (tree basetype_path, tree decl, tree diag_decl) +{ + gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO); + + if (!accessible_p (basetype_path, decl, true)) + { + if (TREE_PRIVATE (decl)) + error ("%q+#D is private", diag_decl); + else if (TREE_PROTECTED (decl)) + error ("%q+#D is protected", diag_decl); + else + error ("%q+#D is inaccessible", diag_decl); + error ("within this context"); + return false; + } + + return true; +} + +/* APPLE LOCAL begin direct-binding-refs 20020224 --turly */ + +/* Should we *really* call a constructor for the object whose reference type + we want? If we have a user conversion function which returns the ref + type directly, there's no need to call the object's constructor as we + can bind directly (dcl.init.ref.) + + These must be exactly the same types. */ + +static int really_call_constructor_p (tree, tree, tree); +static int +really_call_constructor_p (tree expr, tree convfn, tree totype) +{ + /* TEMPORARILY DISABLING THIS "FIX" NOW WE HAVE A SOURCE WORKAROUND. */ + /* However, we'll leave the code here pending input from the FSF + on this issue. */ + + if (0 /* && ! NEED_TEMPORARY_P (convfn) Watch out! this macro is undefined */ + && TREE_CODE (expr) == INDIRECT_REF + && TREE_CODE (TREE_TYPE (convfn)) == METHOD_TYPE + && TREE_CODE (TREE_TYPE (TREE_TYPE (convfn))) == REFERENCE_TYPE + && TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_TYPE (convfn)))) == RECORD_TYPE + && TREE_TYPE (TREE_TYPE (TREE_TYPE (convfn))) == totype + && TREE_TYPE (expr) == totype) + return 0; + + return 1; +} +/* APPLE LOCAL end direct-binding-refs 20020224 --turly */ + +/* Check that a callable constructor to initialize a temporary of + TYPE from an EXPR exists. */ + +static void +check_constructor_callable (tree type, tree expr) +{ + build_special_member_call (NULL_TREE, + complete_ctor_identifier, + build_tree_list (NULL_TREE, expr), + type, + LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING + | LOOKUP_NO_CONVERSION + | LOOKUP_CONSTRUCTOR_CALLABLE); +} + +/* Initialize a temporary of type TYPE with EXPR. The FLAGS are a + bitwise or of LOOKUP_* values. If any errors are warnings are + generated, set *DIAGNOSTIC_FN to "error" or "warning", + respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN + to NULL. */ + +static tree +build_temp (tree expr, tree type, int flags, + diagnostic_fn_t *diagnostic_fn) +{ + int savew, savee; + + savew = warningcount, savee = errorcount; + expr = build_special_member_call (NULL_TREE, + complete_ctor_identifier, + build_tree_list (NULL_TREE, expr), + type, flags); + if (warningcount > savew) + *diagnostic_fn = warning0; + else if (errorcount > savee) + *diagnostic_fn = error; + else + *diagnostic_fn = NULL; + return expr; +} + + +/* Perform the conversions in CONVS on the expression EXPR. FN and + ARGNUM are used for diagnostics. ARGNUM is zero based, -1 + indicates the `this' argument of a method. INNER is nonzero when + being called to continue a conversion chain. It is negative when a + reference binding will be applied, positive otherwise. If + ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious + conversions will be emitted if appropriate. If C_CAST_P is true, + this conversion is coming from a C-style cast; in that case, + conversions to inaccessible bases are permitted. */ + +static tree +convert_like_real (conversion *convs, tree expr, tree fn, int argnum, + int inner, bool issue_conversion_warnings, + bool c_cast_p) +{ + tree totype = convs->type; + diagnostic_fn_t diagnostic_fn; + + if (convs->bad_p + && convs->kind != ck_user + && convs->kind != ck_ambig + && convs->kind != ck_ref_bind) + { + conversion *t = convs; + for (; t; t = convs->u.next) + { + if (t->kind == ck_user || !t->bad_p) + { + expr = convert_like_real (t, expr, fn, argnum, 1, + /*issue_conversion_warnings=*/false, + /*c_cast_p=*/false); + break; + } + else if (t->kind == ck_ambig) + return convert_like_real (t, expr, fn, argnum, 1, + /*issue_conversion_warnings=*/false, + /*c_cast_p=*/false); + else if (t->kind == ck_identity) + break; + } + pedwarn ("invalid conversion from %qT to %qT", TREE_TYPE (expr), totype); + if (fn) + pedwarn (" initializing argument %P of %qD", argnum, fn); + return cp_convert (totype, expr); + } + + if (issue_conversion_warnings) + { + tree t = non_reference (totype); + + /* Issue warnings about peculiar, but valid, uses of NULL. */ + if (ARITHMETIC_TYPE_P (t) && expr == null_node) + { + if (fn) + warning (OPT_Wconversion, "passing NULL to non-pointer argument %P of %qD", + argnum, fn); + else + warning (OPT_Wconversion, "converting to non-pointer type %qT from NULL", t); + } + + /* Warn about assigning a floating-point type to an integer type. */ + if (TREE_CODE (TREE_TYPE (expr)) == REAL_TYPE + && TREE_CODE (t) == INTEGER_TYPE) + { + if (fn) + warning (OPT_Wconversion, "passing %qT for argument %P to %qD", + TREE_TYPE (expr), argnum, fn); + else + warning (OPT_Wconversion, "converting to %qT from %qT", t, TREE_TYPE (expr)); + } + } + + switch (convs->kind) + { + case ck_user: + { + struct z_candidate *cand = convs->cand; + tree convfn = cand->fn; + tree args; + + if (DECL_CONSTRUCTOR_P (convfn)) + { + tree t = build_int_cst (build_pointer_type (DECL_CONTEXT (convfn)), + 0); + + args = build_tree_list (NULL_TREE, expr); + /* We should never try to call the abstract or base constructor + from here. */ + gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (convfn) + && !DECL_HAS_VTT_PARM_P (convfn)); + args = tree_cons (NULL_TREE, t, args); + } + else + args = build_this (expr); + expr = build_over_call (cand, LOOKUP_NORMAL); + + /* If this is a constructor or a function returning an aggr type, + we need to build up a TARGET_EXPR. */ + if (DECL_CONSTRUCTOR_P (convfn)) + expr = build_cplus_new (totype, expr); + + /* The result of the call is then used to direct-initialize the object + that is the destination of the copy-initialization. [dcl.init] + + Note that this step is not reflected in the conversion sequence; + it affects the semantics when we actually perform the + conversion, but is not considered during overload resolution. + + If the target is a class, that means call a ctor. */ + if (IS_AGGR_TYPE (totype) + /* APPLE LOCAL direct-binding-refs 20020224 --turly */ + && really_call_constructor_p (expr, convfn, totype) + && (inner >= 0 || !lvalue_p (expr))) + { + expr = (build_temp + (expr, totype, + /* Core issue 84, now a DR, says that we don't + allow UDCs for these args (which deliberately + breaks copy-init of an auto_ptr<Base> from an + auto_ptr<Derived>). */ + LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING|LOOKUP_NO_CONVERSION, + &diagnostic_fn)); + + if (diagnostic_fn) + { + if (fn) + diagnostic_fn + (" initializing argument %P of %qD from result of %qD", + argnum, fn, convfn); + else + diagnostic_fn + (" initializing temporary from result of %qD", convfn); + } + expr = build_cplus_new (totype, expr); + } + return expr; + } + case ck_identity: + if (type_unknown_p (expr)) + expr = instantiate_type (totype, expr, tf_warning_or_error); + /* Convert a constant to its underlying value, unless we are + about to bind it to a reference, in which case we need to + leave it as an lvalue. */ + if (inner >= 0) + expr = decl_constant_value (expr); + if (convs->check_copy_constructor_p) + check_constructor_callable (totype, expr); + return expr; + case ck_ambig: + /* Call build_user_type_conversion again for the error. */ + return build_user_type_conversion + (totype, convs->u.expr, LOOKUP_NORMAL); + + default: + break; + }; + + expr = convert_like_real (convs->u.next, expr, fn, argnum, + convs->kind == ck_ref_bind ? -1 : 1, + /*issue_conversion_warnings=*/false, + c_cast_p); + if (expr == error_mark_node) + return error_mark_node; + + switch (convs->kind) + { + case ck_rvalue: + expr = convert_bitfield_to_declared_type (expr); + if (! IS_AGGR_TYPE (totype)) + return expr; + /* Else fall through. */ + case ck_base: + if (convs->kind == ck_base && !convs->need_temporary_p) + { + /* We are going to bind a reference directly to a base-class + subobject of EXPR. */ + if (convs->check_copy_constructor_p) + check_constructor_callable (TREE_TYPE (expr), expr); + /* Build an expression for `*((base*) &expr)'. */ + expr = build_unary_op (ADDR_EXPR, expr, 0); + expr = convert_to_base (expr, build_pointer_type (totype), + !c_cast_p, /*nonnull=*/true); + expr = build_indirect_ref (expr, "implicit conversion"); + return expr; + } + + /* Copy-initialization where the cv-unqualified version of the source + type is the same class as, or a derived class of, the class of the + destination [is treated as direct-initialization]. [dcl.init] */ + expr = build_temp (expr, totype, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING, + &diagnostic_fn); + if (diagnostic_fn && fn) + diagnostic_fn (" initializing argument %P of %qD", argnum, fn); + return build_cplus_new (totype, expr); + + case ck_ref_bind: + { + tree ref_type = totype; + + /* If necessary, create a temporary. */ + if (convs->need_temporary_p || !lvalue_p (expr)) + { + tree type = convs->u.next->type; + cp_lvalue_kind lvalue = real_lvalue_p (expr); + + if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type))) + { + /* If the reference is volatile or non-const, we + cannot create a temporary. */ + if (lvalue & clk_bitfield) + error ("cannot bind bitfield %qE to %qT", + expr, ref_type); + else if (lvalue & clk_packed) + error ("cannot bind packed field %qE to %qT", + expr, ref_type); + else + error ("cannot bind rvalue %qE to %qT", expr, ref_type); + return error_mark_node; + } + /* If the source is a packed field, and we must use a copy + constructor, then building the target expr will require + binding the field to the reference parameter to the + copy constructor, and we'll end up with an infinite + loop. If we can use a bitwise copy, then we'll be + OK. */ + if ((lvalue & clk_packed) + && CLASS_TYPE_P (type) + && !TYPE_HAS_TRIVIAL_INIT_REF (type)) + { + error ("cannot bind packed field %qE to %qT", + expr, ref_type); + return error_mark_node; + } + expr = build_target_expr_with_type (expr, type); + } + + /* Take the address of the thing to which we will bind the + reference. */ + expr = build_unary_op (ADDR_EXPR, expr, 1); + if (expr == error_mark_node) + return error_mark_node; + + /* Convert it to a pointer to the type referred to by the + reference. This will adjust the pointer if a derived to + base conversion is being performed. */ + expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)), + expr); + /* Convert the pointer to the desired reference type. */ + return build_nop (ref_type, expr); + } + + case ck_lvalue: + return decay_conversion (expr); + + case ck_qual: + /* Warn about deprecated conversion if appropriate. */ + string_conv_p (totype, expr, 1); + break; + + case ck_ptr: + if (convs->base_p) + expr = convert_to_base (expr, totype, !c_cast_p, + /*nonnull=*/false); + return build_nop (totype, expr); + + case ck_pmem: + return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false, + c_cast_p); + + default: + break; + } + + if (issue_conversion_warnings) + expr = convert_and_check (totype, expr); + else + expr = convert (totype, expr); + + return expr; +} + +/* Build a call to __builtin_trap. */ + +static tree +call_builtin_trap (void) +{ + tree fn = implicit_built_in_decls[BUILT_IN_TRAP]; + + gcc_assert (fn != NULL); + fn = build_call (fn, NULL_TREE); + return fn; +} + +/* ARG is being passed to a varargs function. Perform any conversions + required. Return the converted value. */ + +tree +convert_arg_to_ellipsis (tree arg) +{ + /* [expr.call] + + The lvalue-to-rvalue, array-to-pointer, and function-to-pointer + standard conversions are performed. */ + arg = decay_conversion (arg); + /* [expr.call] + + If the argument has integral or enumeration type that is subject + to the integral promotions (_conv.prom_), or a floating point + type that is subject to the floating point promotion + (_conv.fpprom_), the value of the argument is converted to the + promoted type before the call. */ + if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE + && (TYPE_PRECISION (TREE_TYPE (arg)) + < TYPE_PRECISION (double_type_node))) + arg = convert_to_real (double_type_node, arg); + else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg))) + arg = perform_integral_promotions (arg); + + arg = require_complete_type (arg); + + if (arg != error_mark_node + && !pod_type_p (TREE_TYPE (arg))) + { + /* Undefined behavior [expr.call] 5.2.2/7. We used to just warn + here and do a bitwise copy, but now cp_expr_size will abort if we + try to do that. + If the call appears in the context of a sizeof expression, + there is no need to emit a warning, since the expression won't be + evaluated. We keep the builtin_trap just as a safety check. */ + if (!skip_evaluation) + warning (0, "cannot pass objects of non-POD type %q#T through %<...%>; " + "call will abort at runtime", TREE_TYPE (arg)); + arg = call_builtin_trap (); + arg = build2 (COMPOUND_EXPR, integer_type_node, arg, + integer_zero_node); + } + + return arg; +} + +/* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */ + +tree +build_x_va_arg (tree expr, tree type) +{ + if (processing_template_decl) + return build_min (VA_ARG_EXPR, type, expr); + + type = complete_type_or_else (type, NULL_TREE); + + if (expr == error_mark_node || !type) + return error_mark_node; + + if (! pod_type_p (type)) + { + /* Remove reference types so we don't ICE later on. */ + tree type1 = non_reference (type); + /* Undefined behavior [expr.call] 5.2.2/7. */ + warning (0, "cannot receive objects of non-POD type %q#T through %<...%>; " + "call will abort at runtime", type); + expr = convert (build_pointer_type (type1), null_node); + expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), + call_builtin_trap (), expr); + expr = build_indirect_ref (expr, NULL); + return expr; + } + + return build_va_arg (expr, type); +} + +/* TYPE has been given to va_arg. Apply the default conversions which + would have happened when passed via ellipsis. Return the promoted + type, or the passed type if there is no change. */ + +tree +cxx_type_promotes_to (tree type) +{ + tree promote; + + /* Perform the array-to-pointer and function-to-pointer + conversions. */ + type = type_decays_to (type); + + promote = type_promotes_to (type); + if (same_type_p (type, promote)) + promote = type; + + return promote; +} + +/* ARG is a default argument expression being passed to a parameter of + the indicated TYPE, which is a parameter to FN. Do any required + conversions. Return the converted value. */ + +tree +convert_default_arg (tree type, tree arg, tree fn, int parmnum) +{ + /* If the ARG is an unparsed default argument expression, the + conversion cannot be performed. */ + if (TREE_CODE (arg) == DEFAULT_ARG) + { + error ("the default argument for parameter %d of %qD has " + "not yet been parsed", + parmnum, fn); + return error_mark_node; + } + + if (fn && DECL_TEMPLATE_INFO (fn)) + arg = tsubst_default_argument (fn, type, arg); + + arg = break_out_target_exprs (arg); + + if (TREE_CODE (arg) == CONSTRUCTOR) + { + arg = digest_init (type, arg); + arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL, + "default argument", fn, parmnum); + } + else + { + /* We must make a copy of ARG, in case subsequent processing + alters any part of it. For example, during gimplification a + cast of the form (T) &X::f (where "f" is a member function) + will lead to replacing the PTRMEM_CST for &X::f with a + VAR_DECL. We can avoid the copy for constants, since they + are never modified in place. */ + if (!CONSTANT_CLASS_P (arg)) + arg = unshare_expr (arg); + arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL, + "default argument", fn, parmnum); + arg = convert_for_arg_passing (type, arg); + } + + return arg; +} + +/* Returns the type which will really be used for passing an argument of + type TYPE. */ + +tree +type_passed_as (tree type) +{ + /* Pass classes with copy ctors by invisible reference. */ + if (TREE_ADDRESSABLE (type)) + { + type = build_reference_type (type); + /* There are no other pointers to this temporary. */ + type = build_qualified_type (type, TYPE_QUAL_RESTRICT); + } + else if (targetm.calls.promote_prototypes (type) + && INTEGRAL_TYPE_P (type) + && COMPLETE_TYPE_P (type) + && INT_CST_LT_UNSIGNED (TYPE_SIZE (type), + TYPE_SIZE (integer_type_node))) + type = integer_type_node; + + return type; +} + +/* Actually perform the appropriate conversion. */ + +tree +convert_for_arg_passing (tree type, tree val) +{ + val = convert_bitfield_to_declared_type (val); + if (val == error_mark_node) + ; + /* Pass classes with copy ctors by invisible reference. */ + else if (TREE_ADDRESSABLE (type)) + val = build1 (ADDR_EXPR, build_reference_type (type), val); + else if (targetm.calls.promote_prototypes (type) + && INTEGRAL_TYPE_P (type) + && COMPLETE_TYPE_P (type) + && INT_CST_LT_UNSIGNED (TYPE_SIZE (type), + TYPE_SIZE (integer_type_node))) + val = perform_integral_promotions (val); + if (warn_missing_format_attribute) + { + tree rhstype = TREE_TYPE (val); + const enum tree_code coder = TREE_CODE (rhstype); + const enum tree_code codel = TREE_CODE (type); + if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE) + && coder == codel + && check_missing_format_attribute (type, rhstype)) + warning (OPT_Wmissing_format_attribute, + "argument of function call might be a candidate for a format attribute"); + } + return val; +} + +/* Returns true iff FN is a function with magic varargs, i.e. ones for + which no conversions at all should be done. This is true for some + builtins which don't act like normal functions. */ + +static bool +magic_varargs_p (tree fn) +{ + if (DECL_BUILT_IN (fn)) + switch (DECL_FUNCTION_CODE (fn)) + { + case BUILT_IN_CLASSIFY_TYPE: + case BUILT_IN_CONSTANT_P: + case BUILT_IN_NEXT_ARG: + case BUILT_IN_STDARG_START: + case BUILT_IN_VA_START: + return true; + + default:; + } + + return false; +} + +/* Subroutine of the various build_*_call functions. Overload resolution + has chosen a winning candidate CAND; build up a CALL_EXPR accordingly. + ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a + bitmask of various LOOKUP_* flags which apply to the call itself. */ + +static tree +build_over_call (struct z_candidate *cand, int flags) +{ + tree fn = cand->fn; + tree args = cand->args; + conversion **convs = cand->convs; + conversion *conv; + tree converted_args = NULL_TREE; + tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn)); + tree arg, val; + int i = 0; + int is_method = 0; + + /* In a template, there is no need to perform all of the work that + is normally done. We are only interested in the type of the call + expression, i.e., the return type of the function. Any semantic + errors will be deferred until the template is instantiated. */ + if (processing_template_decl) + { + tree expr; + tree return_type; + return_type = TREE_TYPE (TREE_TYPE (fn)); + expr = build3 (CALL_EXPR, return_type, fn, args, NULL_TREE); + if (TREE_THIS_VOLATILE (fn) && cfun) + current_function_returns_abnormally = 1; + if (!VOID_TYPE_P (return_type)) + require_complete_type (return_type); + return convert_from_reference (expr); + } + + /* Give any warnings we noticed during overload resolution. */ + if (cand->warnings) + { + struct candidate_warning *w; + for (w = cand->warnings; w; w = w->next) + joust (cand, w->loser, 1); + } + + if (DECL_FUNCTION_MEMBER_P (fn)) + { + /* If FN is a template function, two cases must be considered. + For example: + + struct A { + protected: + template <class T> void f(); + }; + template <class T> struct B { + protected: + void g(); + }; + struct C : A, B<int> { + using A::f; // #1 + using B<int>::g; // #2 + }; + + In case #1 where `A::f' is a member template, DECL_ACCESS is + recorded in the primary template but not in its specialization. + We check access of FN using its primary template. + + In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply + because it is a member of class template B, DECL_ACCESS is + recorded in the specialization `B<int>::g'. We cannot use its + primary template because `B<T>::g' and `B<int>::g' may have + different access. */ + if (DECL_TEMPLATE_INFO (fn) + && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn))) + perform_or_defer_access_check (cand->access_path, + DECL_TI_TEMPLATE (fn), fn); + else + perform_or_defer_access_check (cand->access_path, fn, fn); + } + + if (args && TREE_CODE (args) != TREE_LIST) + args = build_tree_list (NULL_TREE, args); + arg = args; + + /* The implicit parameters to a constructor are not considered by overload + resolution, and must be of the proper type. */ + if (DECL_CONSTRUCTOR_P (fn)) + { + converted_args = tree_cons (NULL_TREE, TREE_VALUE (arg), converted_args); + arg = TREE_CHAIN (arg); + parm = TREE_CHAIN (parm); + /* We should never try to call the abstract constructor. */ + gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn)); + + if (DECL_HAS_VTT_PARM_P (fn)) + { + converted_args = tree_cons + (NULL_TREE, TREE_VALUE (arg), converted_args); + arg = TREE_CHAIN (arg); + parm = TREE_CHAIN (parm); + } + } + /* Bypass access control for 'this' parameter. */ + else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE) + { + tree parmtype = TREE_VALUE (parm); + tree argtype = TREE_TYPE (TREE_VALUE (arg)); + tree converted_arg; + tree base_binfo; + + if (convs[i]->bad_p) + pedwarn ("passing %qT as %<this%> argument of %q#D discards qualifiers", + TREE_TYPE (argtype), fn); + + /* [class.mfct.nonstatic]: If a nonstatic member function of a class + X is called for an object that is not of type X, or of a type + derived from X, the behavior is undefined. + + So we can assume that anything passed as 'this' is non-null, and + optimize accordingly. */ + gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE); + /* Convert to the base in which the function was declared. */ + gcc_assert (cand->conversion_path != NULL_TREE); + converted_arg = build_base_path (PLUS_EXPR, + TREE_VALUE (arg), + cand->conversion_path, + 1); + /* Check that the base class is accessible. */ + if (!accessible_base_p (TREE_TYPE (argtype), + BINFO_TYPE (cand->conversion_path), true)) + error ("%qT is not an accessible base of %qT", + BINFO_TYPE (cand->conversion_path), + TREE_TYPE (argtype)); + /* If fn was found by a using declaration, the conversion path + will be to the derived class, not the base declaring fn. We + must convert from derived to base. */ + base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)), + TREE_TYPE (parmtype), ba_unique, NULL); + converted_arg = build_base_path (PLUS_EXPR, converted_arg, + base_binfo, 1); + + converted_args = tree_cons (NULL_TREE, converted_arg, converted_args); + parm = TREE_CHAIN (parm); + arg = TREE_CHAIN (arg); + ++i; + is_method = 1; + } + + for (; arg && parm; + parm = TREE_CHAIN (parm), arg = TREE_CHAIN (arg), ++i) + { + tree type = TREE_VALUE (parm); + + conv = convs[i]; + + /* Don't make a copy here if build_call is going to. */ + if (conv->kind == ck_rvalue + && !TREE_ADDRESSABLE (complete_type (type))) + conv = conv->u.next; + + val = convert_like_with_context + (conv, TREE_VALUE (arg), fn, i - is_method); + + val = convert_for_arg_passing (type, val); + converted_args = tree_cons (NULL_TREE, val, converted_args); + } + + /* Default arguments */ + for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++) + converted_args + = tree_cons (NULL_TREE, + convert_default_arg (TREE_VALUE (parm), + TREE_PURPOSE (parm), + fn, i - is_method), + converted_args); + + /* Ellipsis */ + for (; arg; arg = TREE_CHAIN (arg)) + { + tree a = TREE_VALUE (arg); + if (magic_varargs_p (fn)) + /* Do no conversions for magic varargs. */; + else + a = convert_arg_to_ellipsis (a); + converted_args = tree_cons (NULL_TREE, a, converted_args); + } + + converted_args = nreverse (converted_args); + + check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)), + converted_args, TYPE_ARG_TYPES (TREE_TYPE (fn))); + + /* Avoid actually calling copy constructors and copy assignment operators, + if possible. */ + + if (! flag_elide_constructors) + /* Do things the hard way. */; + else if (cand->num_convs == 1 && DECL_COPY_CONSTRUCTOR_P (fn)) + { + tree targ; + arg = skip_artificial_parms_for (fn, converted_args); + arg = TREE_VALUE (arg); + + /* Pull out the real argument, disregarding const-correctness. */ + targ = arg; + while (TREE_CODE (targ) == NOP_EXPR + || TREE_CODE (targ) == NON_LVALUE_EXPR + || TREE_CODE (targ) == CONVERT_EXPR) + targ = TREE_OPERAND (targ, 0); + if (TREE_CODE (targ) == ADDR_EXPR) + { + targ = TREE_OPERAND (targ, 0); + if (!same_type_ignoring_top_level_qualifiers_p + (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ))) + targ = NULL_TREE; + } + else + targ = NULL_TREE; + + if (targ) + arg = targ; + else + arg = build_indirect_ref (arg, 0); + + /* [class.copy]: the copy constructor is implicitly defined even if + the implementation elided its use. */ + if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn))) + mark_used (fn); + + /* If we're creating a temp and we already have one, don't create a + new one. If we're not creating a temp but we get one, use + INIT_EXPR to collapse the temp into our target. Otherwise, if the + ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a + temp or an INIT_EXPR otherwise. */ + if (integer_zerop (TREE_VALUE (args))) + { + if (TREE_CODE (arg) == TARGET_EXPR) + return arg; + else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn))) + return build_target_expr_with_type (arg, DECL_CONTEXT (fn)); + } + else if (TREE_CODE (arg) == TARGET_EXPR + || TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn))) + { + tree to = stabilize_reference + (build_indirect_ref (TREE_VALUE (args), 0)); + + val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg); + return val; + } + } + else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR + && copy_fn_p (fn) + && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn))) + { + tree to = stabilize_reference + (build_indirect_ref (TREE_VALUE (converted_args), 0)); + tree type = TREE_TYPE (to); + tree as_base = CLASSTYPE_AS_BASE (type); + + arg = TREE_VALUE (TREE_CHAIN (converted_args)); + if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base))) + { + arg = build_indirect_ref (arg, 0); + val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg); + } + else + { + /* We must only copy the non-tail padding parts. + Use __builtin_memcpy for the bitwise copy. */ + + tree args, t; + + args = tree_cons (NULL, TYPE_SIZE_UNIT (as_base), NULL); + args = tree_cons (NULL, arg, args); + t = build_unary_op (ADDR_EXPR, to, 0); + args = tree_cons (NULL, t, args); + t = implicit_built_in_decls[BUILT_IN_MEMCPY]; + t = build_call (t, args); + + t = convert (TREE_TYPE (TREE_VALUE (args)), t); + val = build_indirect_ref (t, 0); + } + + return val; + } + + mark_used (fn); + + /* APPLE LOCAL begin KEXT indirect-virtual-calls --sts */ + if (DECL_VINDEX (fn) + && (TARGET_KEXTABI + || (flags & LOOKUP_NONVIRTUAL) == 0)) + /* APPLE LOCAL end KEXT indirect-virtual-calls --sts */ + { + tree t, *p = &TREE_VALUE (converted_args); + tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (*p)), + DECL_CONTEXT (fn), + ba_any, NULL); + gcc_assert (binfo && binfo != error_mark_node); + + *p = build_base_path (PLUS_EXPR, *p, binfo, 1); + if (TREE_SIDE_EFFECTS (*p)) + *p = save_expr (*p); + t = build_pointer_type (TREE_TYPE (fn)); + if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn))) + fn = build_java_interface_fn_ref (fn, *p); + /* APPLE LOCAL begin KEXT indirect-virtual-calls --sts */ + /* If this is not really supposed to be a virtual call, find the + vtable corresponding to the correct type, and use it. */ + else if (flags & LOOKUP_NONVIRTUAL) { + tree call_site_type = TREE_TYPE (cand->access_path); + tree fn_class_type = DECL_CLASS_CONTEXT (fn); + + gcc_assert (call_site_type != NULL && + fn_class_type != NULL && + AGGREGATE_TYPE_P (call_site_type) && + AGGREGATE_TYPE_P (fn_class_type)); + gcc_assert (lookup_base(TYPE_MAIN_VARIANT (call_site_type), + TYPE_MAIN_VARIANT (fn_class_type), + ba_any | ba_quiet, + NULL) != NULL); + + if (BINFO_N_BASE_BINFOS (TYPE_BINFO (call_site_type)) > 1 + || CLASSTYPE_VBASECLASSES (call_site_type)) + error ("indirect virtual calls are invalid for a type that uses multiple or virtual inheritance"); + + fn = (build_vfn_ref_using_vtable + (BINFO_VTABLE (TYPE_BINFO (call_site_type)), + DECL_VINDEX (fn))); + /* We have to construct something for which we can directly + alter the TREE_TYPE. We can't allow the INDIRECT_REF built + above to be so altered, as that would be invalid. */ + fn = build1 (NOP_EXPR, t, fn); + } + /* APPLE LOCAL end KEXT indirect-virtual-calls --sts */ + else + fn = build_vfn_ref (*p, DECL_VINDEX (fn)); + TREE_TYPE (fn) = t; + } + else if (DECL_INLINE (fn)) + fn = inline_conversion (fn); + else + fn = build_addr_func (fn); + + return build_cxx_call (fn, converted_args); +} + +/* Build and return a call to FN, using ARGS. This function performs + no overload resolution, conversion, or other high-level + operations. */ + +tree +build_cxx_call (tree fn, tree args) +{ + tree fndecl; + + fn = build_call (fn, args); + + /* If this call might throw an exception, note that fact. */ + fndecl = get_callee_fndecl (fn); + if ((!fndecl || !TREE_NOTHROW (fndecl)) + && at_function_scope_p () + && cfun) + cp_function_chain->can_throw = 1; + + /* Some built-in function calls will be evaluated at compile-time in + fold (). */ + fn = fold_if_not_in_template (fn); + + if (VOID_TYPE_P (TREE_TYPE (fn))) + return fn; + + fn = require_complete_type (fn); + if (fn == error_mark_node) + return error_mark_node; + + if (IS_AGGR_TYPE (TREE_TYPE (fn))) + fn = build_cplus_new (TREE_TYPE (fn), fn); + return convert_from_reference (fn); +} + +static GTY(()) tree java_iface_lookup_fn; + +/* Make an expression which yields the address of the Java interface + method FN. This is achieved by generating a call to libjava's + _Jv_LookupInterfaceMethodIdx(). */ + +static tree +build_java_interface_fn_ref (tree fn, tree instance) +{ + tree lookup_args, lookup_fn, method, idx; + tree klass_ref, iface, iface_ref; + int i; + + if (!java_iface_lookup_fn) + { + tree endlink = build_void_list_node (); + tree t = tree_cons (NULL_TREE, ptr_type_node, + tree_cons (NULL_TREE, ptr_type_node, + tree_cons (NULL_TREE, java_int_type_node, + endlink))); + java_iface_lookup_fn + = builtin_function ("_Jv_LookupInterfaceMethodIdx", + build_function_type (ptr_type_node, t), + 0, NOT_BUILT_IN, NULL, NULL_TREE); + } + + /* Look up the pointer to the runtime java.lang.Class object for `instance'. + This is the first entry in the vtable. */ + klass_ref = build_vtbl_ref (build_indirect_ref (instance, 0), + integer_zero_node); + + /* Get the java.lang.Class pointer for the interface being called. */ + iface = DECL_CONTEXT (fn); + iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false); + if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL + || DECL_CONTEXT (iface_ref) != iface) + { + error ("could not find class$ field in java interface type %qT", + iface); + return error_mark_node; + } + iface_ref = build_address (iface_ref); + iface_ref = convert (build_pointer_type (iface), iface_ref); + + /* Determine the itable index of FN. */ + i = 1; + for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method)) + { + if (!DECL_VIRTUAL_P (method)) + continue; + if (fn == method) + break; + i++; + } + idx = build_int_cst (NULL_TREE, i); + + lookup_args = tree_cons (NULL_TREE, klass_ref, + tree_cons (NULL_TREE, iface_ref, + build_tree_list (NULL_TREE, idx))); + lookup_fn = build1 (ADDR_EXPR, + build_pointer_type (TREE_TYPE (java_iface_lookup_fn)), + java_iface_lookup_fn); + return build3 (CALL_EXPR, ptr_type_node, lookup_fn, lookup_args, NULL_TREE); +} + +/* Returns the value to use for the in-charge parameter when making a + call to a function with the indicated NAME. + + FIXME:Can't we find a neater way to do this mapping? */ + +tree +in_charge_arg_for_name (tree name) +{ + if (name == base_ctor_identifier + || name == base_dtor_identifier) + return integer_zero_node; + else if (name == complete_ctor_identifier) + return integer_one_node; + else if (name == complete_dtor_identifier) + return integer_two_node; + else if (name == deleting_dtor_identifier) + return integer_three_node; + + /* This function should only be called with one of the names listed + above. */ + gcc_unreachable (); + return NULL_TREE; +} + +/* Build a call to a constructor, destructor, or an assignment + operator for INSTANCE, an expression with class type. NAME + indicates the special member function to call; ARGS are the + arguments. BINFO indicates the base of INSTANCE that is to be + passed as the `this' parameter to the member function called. + + FLAGS are the LOOKUP_* flags to use when processing the call. + + If NAME indicates a complete object constructor, INSTANCE may be + NULL_TREE. In this case, the caller will call build_cplus_new to + store the newly constructed object into a VAR_DECL. */ + +tree +build_special_member_call (tree instance, tree name, tree args, + tree binfo, int flags) +{ + tree fns; + /* The type of the subobject to be constructed or destroyed. */ + tree class_type; + + gcc_assert (name == complete_ctor_identifier + || name == base_ctor_identifier + || name == complete_dtor_identifier + || name == base_dtor_identifier + || name == deleting_dtor_identifier + || name == ansi_assopname (NOP_EXPR)); + if (TYPE_P (binfo)) + { + /* Resolve the name. */ + if (!complete_type_or_else (binfo, NULL_TREE)) + return error_mark_node; + + binfo = TYPE_BINFO (binfo); + } + + gcc_assert (binfo != NULL_TREE); + + class_type = BINFO_TYPE (binfo); + + /* Handle the special case where INSTANCE is NULL_TREE. */ + if (name == complete_ctor_identifier && !instance) + { + instance = build_int_cst (build_pointer_type (class_type), 0); + instance = build1 (INDIRECT_REF, class_type, instance); + } + else + { + if (name == complete_dtor_identifier + || name == base_dtor_identifier + || name == deleting_dtor_identifier) + gcc_assert (args == NULL_TREE); + + /* Convert to the base class, if necessary. */ + if (!same_type_ignoring_top_level_qualifiers_p + (TREE_TYPE (instance), BINFO_TYPE (binfo))) + { + if (name != ansi_assopname (NOP_EXPR)) + /* For constructors and destructors, either the base is + non-virtual, or it is virtual but we are doing the + conversion from a constructor or destructor for the + complete object. In either case, we can convert + statically. */ + instance = convert_to_base_statically (instance, binfo); + else + /* However, for assignment operators, we must convert + dynamically if the base is virtual. */ + instance = build_base_path (PLUS_EXPR, instance, + binfo, /*nonnull=*/1); + } + } + + gcc_assert (instance != NULL_TREE); + + fns = lookup_fnfields (binfo, name, 1); + + /* When making a call to a constructor or destructor for a subobject + that uses virtual base classes, pass down a pointer to a VTT for + the subobject. */ + if ((name == base_ctor_identifier + || name == base_dtor_identifier) + && CLASSTYPE_VBASECLASSES (class_type)) + { + tree vtt; + tree sub_vtt; + + /* If the current function is a complete object constructor + or destructor, then we fetch the VTT directly. + Otherwise, we look it up using the VTT we were given. */ + vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type)); + vtt = decay_conversion (vtt); + vtt = build3 (COND_EXPR, TREE_TYPE (vtt), + build2 (EQ_EXPR, boolean_type_node, + current_in_charge_parm, integer_zero_node), + current_vtt_parm, + vtt); + gcc_assert (BINFO_SUBVTT_INDEX (binfo)); + sub_vtt = build2 (PLUS_EXPR, TREE_TYPE (vtt), vtt, + BINFO_SUBVTT_INDEX (binfo)); + + args = tree_cons (NULL_TREE, sub_vtt, args); + } + + return build_new_method_call (instance, fns, args, + TYPE_BINFO (BINFO_TYPE (binfo)), + flags, /*fn=*/NULL); +} + +/* Return the NAME, as a C string. The NAME indicates a function that + is a member of TYPE. *FREE_P is set to true if the caller must + free the memory returned. + + Rather than go through all of this, we should simply set the names + of constructors and destructors appropriately, and dispense with + ctor_identifier, dtor_identifier, etc. */ + +static char * +name_as_c_string (tree name, tree type, bool *free_p) +{ + char *pretty_name; + + /* Assume that we will not allocate memory. */ + *free_p = false; + /* Constructors and destructors are special. */ + if (IDENTIFIER_CTOR_OR_DTOR_P (name)) + { + pretty_name + = (char *) IDENTIFIER_POINTER (constructor_name (type)); + /* For a destructor, add the '~'. */ + if (name == complete_dtor_identifier + || name == base_dtor_identifier + || name == deleting_dtor_identifier) + { + pretty_name = concat ("~", pretty_name, NULL); + /* Remember that we need to free the memory allocated. */ + *free_p = true; + } + } + else if (IDENTIFIER_TYPENAME_P (name)) + { + pretty_name = concat ("operator ", + type_as_string (TREE_TYPE (name), + TFF_PLAIN_IDENTIFIER), + NULL); + /* Remember that we need to free the memory allocated. */ + *free_p = true; + } + else + pretty_name = (char *) IDENTIFIER_POINTER (name); + + return pretty_name; +} + +/* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will + be set, upon return, to the function called. */ + +tree +build_new_method_call (tree instance, tree fns, tree args, + tree conversion_path, int flags, + tree *fn_p) +{ + struct z_candidate *candidates = 0, *cand; + tree explicit_targs = NULL_TREE; + tree basetype = NULL_TREE; + tree access_binfo; + tree optype; + tree mem_args = NULL_TREE, instance_ptr; + tree name; + tree user_args; + tree call; + tree fn; + tree class_type; + int template_only = 0; + bool any_viable_p; + tree orig_instance; + tree orig_fns; + tree orig_args; + void *p; + + gcc_assert (instance != NULL_TREE); + + /* We don't know what function we're going to call, yet. */ + if (fn_p) + *fn_p = NULL_TREE; + + if (error_operand_p (instance) + || error_operand_p (fns) + || args == error_mark_node) + return error_mark_node; + + if (!BASELINK_P (fns)) + { + error ("call to non-function %qD", fns); + return error_mark_node; + } + + orig_instance = instance; + orig_fns = fns; + orig_args = args; + + /* Dismantle the baselink to collect all the information we need. */ + if (!conversion_path) + conversion_path = BASELINK_BINFO (fns); + access_binfo = BASELINK_ACCESS_BINFO (fns); + optype = BASELINK_OPTYPE (fns); + fns = BASELINK_FUNCTIONS (fns); + if (TREE_CODE (fns) == TEMPLATE_ID_EXPR) + { + explicit_targs = TREE_OPERAND (fns, 1); + fns = TREE_OPERAND (fns, 0); + template_only = 1; + } + gcc_assert (TREE_CODE (fns) == FUNCTION_DECL + || TREE_CODE (fns) == TEMPLATE_DECL + || TREE_CODE (fns) == OVERLOAD); + fn = get_first_fn (fns); + name = DECL_NAME (fn); + + basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance)); + gcc_assert (CLASS_TYPE_P (basetype)); + + if (processing_template_decl) + { + instance = build_non_dependent_expr (instance); + args = build_non_dependent_args (orig_args); + } + + /* The USER_ARGS are the arguments we will display to users if an + error occurs. The USER_ARGS should not include any + compiler-generated arguments. The "this" pointer hasn't been + added yet. However, we must remove the VTT pointer if this is a + call to a base-class constructor or destructor. */ + user_args = args; + if (IDENTIFIER_CTOR_OR_DTOR_P (name)) + { + /* Callers should explicitly indicate whether they want to construct + the complete object or just the part without virtual bases. */ + gcc_assert (name != ctor_identifier); + /* Similarly for destructors. */ + gcc_assert (name != dtor_identifier); + /* Remove the VTT pointer, if present. */ + if ((name == base_ctor_identifier || name == base_dtor_identifier) + && CLASSTYPE_VBASECLASSES (basetype)) + user_args = TREE_CHAIN (user_args); + } + + /* Process the argument list. */ + args = resolve_args (args); + if (args == error_mark_node) + return error_mark_node; + + instance_ptr = build_this (instance); + + /* It's OK to call destructors on cv-qualified objects. Therefore, + convert the INSTANCE_PTR to the unqualified type, if necessary. */ + if (DECL_DESTRUCTOR_P (fn)) + { + tree type = build_pointer_type (basetype); + if (!same_type_p (type, TREE_TYPE (instance_ptr))) + instance_ptr = build_nop (type, instance_ptr); + name = complete_dtor_identifier; + } + + class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE); + mem_args = tree_cons (NULL_TREE, instance_ptr, args); + + /* Get the high-water mark for the CONVERSION_OBSTACK. */ + p = conversion_obstack_alloc (0); + + for (fn = fns; fn; fn = OVL_NEXT (fn)) + { + tree t = OVL_CURRENT (fn); + tree this_arglist; + + /* We can end up here for copy-init of same or base class. */ + if ((flags & LOOKUP_ONLYCONVERTING) + && DECL_NONCONVERTING_P (t)) + continue; + + if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t)) + this_arglist = mem_args; + else + this_arglist = args; + + if (TREE_CODE (t) == TEMPLATE_DECL) + /* A member template. */ + add_template_candidate (&candidates, t, + class_type, + explicit_targs, + this_arglist, optype, + access_binfo, + conversion_path, + flags, + DEDUCE_CALL); + else if (! template_only) + add_function_candidate (&candidates, t, + class_type, + this_arglist, + access_binfo, + conversion_path, + flags); + } + + candidates = splice_viable (candidates, pedantic, &any_viable_p); + if (!any_viable_p) + { + if (!COMPLETE_TYPE_P (basetype)) + cxx_incomplete_type_error (instance_ptr, basetype); + else + { + char *pretty_name; + bool free_p; + + pretty_name = name_as_c_string (name, basetype, &free_p); + error ("no matching function for call to %<%T::%s(%A)%#V%>", + basetype, pretty_name, user_args, + TREE_TYPE (TREE_TYPE (instance_ptr))); + if (free_p) + free (pretty_name); + } + print_z_candidates (candidates); + call = error_mark_node; + } + else + { + cand = tourney (candidates); + if (cand == 0) + { + char *pretty_name; + bool free_p; + + pretty_name = name_as_c_string (name, basetype, &free_p); + error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name, + user_args); + print_z_candidates (candidates); + if (free_p) + free (pretty_name); + call = error_mark_node; + } + else + { + fn = cand->fn; + + if (!(flags & LOOKUP_NONVIRTUAL) + && DECL_PURE_VIRTUAL_P (fn) + && instance == current_class_ref + && (DECL_CONSTRUCTOR_P (current_function_decl) + || DECL_DESTRUCTOR_P (current_function_decl))) + /* This is not an error, it is runtime undefined + behavior. */ + warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ? + "abstract virtual %q#D called from constructor" + : "abstract virtual %q#D called from destructor"), + fn); + + if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE + && is_dummy_object (instance_ptr)) + { + error ("cannot call member function %qD without object", + fn); + call = error_mark_node; + } + else + { + if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL) + && resolves_to_fixed_type_p (instance, 0)) + flags |= LOOKUP_NONVIRTUAL; + /* Now we know what function is being called. */ + if (fn_p) + *fn_p = fn; + /* Build the actual CALL_EXPR. */ + call = build_over_call (cand, flags); + /* In an expression of the form `a->f()' where `f' turns + out to be a static member function, `a' is + none-the-less evaluated. */ + if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE + && !is_dummy_object (instance_ptr) + && TREE_SIDE_EFFECTS (instance_ptr)) + call = build2 (COMPOUND_EXPR, TREE_TYPE (call), + instance_ptr, call); + else if (call != error_mark_node + && DECL_DESTRUCTOR_P (cand->fn) + && !VOID_TYPE_P (TREE_TYPE (call))) + /* An explicit call of the form "x->~X()" has type + "void". However, on platforms where destructors + return "this" (i.e., those where + targetm.cxx.cdtor_returns_this is true), such calls + will appear to have a return value of pointer type + to the low-level call machinery. We do not want to + change the low-level machinery, since we want to be + able to optimize "delete f()" on such platforms as + "operator delete(~X(f()))" (rather than generating + "t = f(), ~X(t), operator delete (t)"). */ + call = build_nop (void_type_node, call); + } + } + } + + if (processing_template_decl && call != error_mark_node) + call = (build_min_non_dep + (CALL_EXPR, call, + build_min_nt (COMPONENT_REF, orig_instance, orig_fns, NULL_TREE), + orig_args, NULL_TREE)); + + /* Free all the conversions we allocated. */ + obstack_free (&conversion_obstack, p); + + return call; +} + +/* Returns true iff standard conversion sequence ICS1 is a proper + subsequence of ICS2. */ + +static bool +is_subseq (conversion *ics1, conversion *ics2) +{ + /* We can assume that a conversion of the same code + between the same types indicates a subsequence since we only get + here if the types we are converting from are the same. */ + + while (ics1->kind == ck_rvalue + || ics1->kind == ck_lvalue) + ics1 = ics1->u.next; + + while (1) + { + while (ics2->kind == ck_rvalue + || ics2->kind == ck_lvalue) + ics2 = ics2->u.next; + + if (ics2->kind == ck_user + || ics2->kind == ck_ambig + || ics2->kind == ck_identity) + /* At this point, ICS1 cannot be a proper subsequence of + ICS2. We can get a USER_CONV when we are comparing the + second standard conversion sequence of two user conversion + sequences. */ + return false; + + ics2 = ics2->u.next; + + if (ics2->kind == ics1->kind + && same_type_p (ics2->type, ics1->type) + && same_type_p (ics2->u.next->type, + ics1->u.next->type)) + return true; + } +} + +/* Returns nonzero iff DERIVED is derived from BASE. The inputs may + be any _TYPE nodes. */ + +bool +is_properly_derived_from (tree derived, tree base) +{ + if (!IS_AGGR_TYPE_CODE (TREE_CODE (derived)) + || !IS_AGGR_TYPE_CODE (TREE_CODE (base))) + return false; + + /* We only allow proper derivation here. The DERIVED_FROM_P macro + considers every class derived from itself. */ + return (!same_type_ignoring_top_level_qualifiers_p (derived, base) + && DERIVED_FROM_P (base, derived)); +} + +/* We build the ICS for an implicit object parameter as a pointer + conversion sequence. However, such a sequence should be compared + as if it were a reference conversion sequence. If ICS is the + implicit conversion sequence for an implicit object parameter, + modify it accordingly. */ + +static void +maybe_handle_implicit_object (conversion **ics) +{ + if ((*ics)->this_p) + { + /* [over.match.funcs] + + For non-static member functions, the type of the + implicit object parameter is "reference to cv X" + where X is the class of which the function is a + member and cv is the cv-qualification on the member + function declaration. */ + conversion *t = *ics; + tree reference_type; + + /* The `this' parameter is a pointer to a class type. Make the + implicit conversion talk about a reference to that same class + type. */ + reference_type = TREE_TYPE (t->type); + reference_type = build_reference_type (reference_type); + + if (t->kind == ck_qual) + t = t->u.next; + if (t->kind == ck_ptr) + t = t->u.next; + t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE); + t = direct_reference_binding (reference_type, t); + *ics = t; + } +} + +/* If *ICS is a REF_BIND set *ICS to the remainder of the conversion, + and return the type to which the reference refers. Otherwise, + leave *ICS unchanged and return NULL_TREE. */ + +static tree +maybe_handle_ref_bind (conversion **ics) +{ + if ((*ics)->kind == ck_ref_bind) + { + conversion *old_ics = *ics; + tree type = TREE_TYPE (old_ics->type); + *ics = old_ics->u.next; + (*ics)->user_conv_p = old_ics->user_conv_p; + (*ics)->bad_p = old_ics->bad_p; + return type; + } + + return NULL_TREE; +} + +/* Compare two implicit conversion sequences according to the rules set out in + [over.ics.rank]. Return values: + + 1: ics1 is better than ics2 + -1: ics2 is better than ics1 + 0: ics1 and ics2 are indistinguishable */ + +static int +compare_ics (conversion *ics1, conversion *ics2) +{ + tree from_type1; + tree from_type2; + tree to_type1; + tree to_type2; + tree deref_from_type1 = NULL_TREE; + tree deref_from_type2 = NULL_TREE; + tree deref_to_type1 = NULL_TREE; + tree deref_to_type2 = NULL_TREE; + conversion_rank rank1, rank2; + + /* REF_BINDING is nonzero if the result of the conversion sequence + is a reference type. In that case TARGET_TYPE is the + type referred to by the reference. */ + tree target_type1; + tree target_type2; + + /* Handle implicit object parameters. */ + maybe_handle_implicit_object (&ics1); + maybe_handle_implicit_object (&ics2); + + /* Handle reference parameters. */ + target_type1 = maybe_handle_ref_bind (&ics1); + target_type2 = maybe_handle_ref_bind (&ics2); + + /* [over.ics.rank] + + When comparing the basic forms of implicit conversion sequences (as + defined in _over.best.ics_) + + --a standard conversion sequence (_over.ics.scs_) is a better + conversion sequence than a user-defined conversion sequence + or an ellipsis conversion sequence, and + + --a user-defined conversion sequence (_over.ics.user_) is a + better conversion sequence than an ellipsis conversion sequence + (_over.ics.ellipsis_). */ + rank1 = CONVERSION_RANK (ics1); + rank2 = CONVERSION_RANK (ics2); + + if (rank1 > rank2) + return -1; + else if (rank1 < rank2) + return 1; + + if (rank1 == cr_bad) + { + /* XXX Isn't this an extension? */ + /* Both ICS are bad. We try to make a decision based on what + would have happened if they'd been good. */ + if (ics1->user_conv_p > ics2->user_conv_p + || ics1->rank > ics2->rank) + return -1; + else if (ics1->user_conv_p < ics2->user_conv_p + || ics1->rank < ics2->rank) + return 1; + + /* We couldn't make up our minds; try to figure it out below. */ + } + + if (ics1->ellipsis_p) + /* Both conversions are ellipsis conversions. */ + return 0; + + /* User-defined conversion sequence U1 is a better conversion sequence + than another user-defined conversion sequence U2 if they contain the + same user-defined conversion operator or constructor and if the sec- + ond standard conversion sequence of U1 is better than the second + standard conversion sequence of U2. */ + + if (ics1->user_conv_p) + { + conversion *t1; + conversion *t2; + + for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next) + if (t1->kind == ck_ambig) + return 0; + for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next) + if (t2->kind == ck_ambig) + return 0; + + if (t1->cand->fn != t2->cand->fn) + return 0; + + /* We can just fall through here, after setting up + FROM_TYPE1 and FROM_TYPE2. */ + from_type1 = t1->type; + from_type2 = t2->type; + } + else + { + conversion *t1; + conversion *t2; + + /* We're dealing with two standard conversion sequences. + + [over.ics.rank] + + Standard conversion sequence S1 is a better conversion + sequence than standard conversion sequence S2 if + + --S1 is a proper subsequence of S2 (comparing the conversion + sequences in the canonical form defined by _over.ics.scs_, + excluding any Lvalue Transformation; the identity + conversion sequence is considered to be a subsequence of + any non-identity conversion sequence */ + + t1 = ics1; + while (t1->kind != ck_identity) + t1 = t1->u.next; + from_type1 = t1->type; + + t2 = ics2; + while (t2->kind != ck_identity) + t2 = t2->u.next; + from_type2 = t2->type; + } + + if (same_type_p (from_type1, from_type2)) + { + if (is_subseq (ics1, ics2)) + return 1; + if (is_subseq (ics2, ics1)) + return -1; + } + /* Otherwise, one sequence cannot be a subsequence of the other; they + don't start with the same type. This can happen when comparing the + second standard conversion sequence in two user-defined conversion + sequences. */ + + /* [over.ics.rank] + + Or, if not that, + + --the rank of S1 is better than the rank of S2 (by the rules + defined below): + + Standard conversion sequences are ordered by their ranks: an Exact + Match is a better conversion than a Promotion, which is a better + conversion than a Conversion. + + Two conversion sequences with the same rank are indistinguishable + unless one of the following rules applies: + + --A conversion that is not a conversion of a pointer, or pointer + to member, to bool is better than another conversion that is such + a conversion. + + The ICS_STD_RANK automatically handles the pointer-to-bool rule, + so that we do not have to check it explicitly. */ + if (ics1->rank < ics2->rank) + return 1; + else if (ics2->rank < ics1->rank) + return -1; + + to_type1 = ics1->type; + to_type2 = ics2->type; + + if (TYPE_PTR_P (from_type1) + && TYPE_PTR_P (from_type2) + && TYPE_PTR_P (to_type1) + && TYPE_PTR_P (to_type2)) + { + deref_from_type1 = TREE_TYPE (from_type1); + deref_from_type2 = TREE_TYPE (from_type2); + deref_to_type1 = TREE_TYPE (to_type1); + deref_to_type2 = TREE_TYPE (to_type2); + } + /* The rules for pointers to members A::* are just like the rules + for pointers A*, except opposite: if B is derived from A then + A::* converts to B::*, not vice versa. For that reason, we + switch the from_ and to_ variables here. */ + else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2) + && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2)) + || (TYPE_PTRMEMFUNC_P (from_type1) + && TYPE_PTRMEMFUNC_P (from_type2) + && TYPE_PTRMEMFUNC_P (to_type1) + && TYPE_PTRMEMFUNC_P (to_type2))) + { + deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1); + deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2); + deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1); + deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2); + } + + if (deref_from_type1 != NULL_TREE + && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type1)) + && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type2))) + { + /* This was one of the pointer or pointer-like conversions. + + [over.ics.rank] + + --If class B is derived directly or indirectly from class A, + conversion of B* to A* is better than conversion of B* to + void*, and conversion of A* to void* is better than + conversion of B* to void*. */ + if (TREE_CODE (deref_to_type1) == VOID_TYPE + && TREE_CODE (deref_to_type2) == VOID_TYPE) + { + if (is_properly_derived_from (deref_from_type1, + deref_from_type2)) + return -1; + else if (is_properly_derived_from (deref_from_type2, + deref_from_type1)) + return 1; + } + else if (TREE_CODE (deref_to_type1) == VOID_TYPE + || TREE_CODE (deref_to_type2) == VOID_TYPE) + { + if (same_type_p (deref_from_type1, deref_from_type2)) + { + if (TREE_CODE (deref_to_type2) == VOID_TYPE) + { + if (is_properly_derived_from (deref_from_type1, + deref_to_type1)) + return 1; + } + /* We know that DEREF_TO_TYPE1 is `void' here. */ + else if (is_properly_derived_from (deref_from_type1, + deref_to_type2)) + return -1; + } + } + else if (IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type1)) + && IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type2))) + { + /* [over.ics.rank] + + --If class B is derived directly or indirectly from class A + and class C is derived directly or indirectly from B, + + --conversion of C* to B* is better than conversion of C* to + A*, + + --conversion of B* to A* is better than conversion of C* to + A* */ + if (same_type_p (deref_from_type1, deref_from_type2)) + { + if (is_properly_derived_from (deref_to_type1, + deref_to_type2)) + return 1; + else if (is_properly_derived_from (deref_to_type2, + deref_to_type1)) + return -1; + } + else if (same_type_p (deref_to_type1, deref_to_type2)) + { + if (is_properly_derived_from (deref_from_type2, + deref_from_type1)) + return 1; + else if (is_properly_derived_from (deref_from_type1, + deref_from_type2)) + return -1; + } + } + } + else if (CLASS_TYPE_P (non_reference (from_type1)) + && same_type_p (from_type1, from_type2)) + { + tree from = non_reference (from_type1); + + /* [over.ics.rank] + + --binding of an expression of type C to a reference of type + B& is better than binding an expression of type C to a + reference of type A& + + --conversion of C to B is better than conversion of C to A, */ + if (is_properly_derived_from (from, to_type1) + && is_properly_derived_from (from, to_type2)) + { + if (is_properly_derived_from (to_type1, to_type2)) + return 1; + else if (is_properly_derived_from (to_type2, to_type1)) + return -1; + } + } + else if (CLASS_TYPE_P (non_reference (to_type1)) + && same_type_p (to_type1, to_type2)) + { + tree to = non_reference (to_type1); + + /* [over.ics.rank] + + --binding of an expression of type B to a reference of type + A& is better than binding an expression of type C to a + reference of type A&, + + --conversion of B to A is better than conversion of C to A */ + if (is_properly_derived_from (from_type1, to) + && is_properly_derived_from (from_type2, to)) + { + if (is_properly_derived_from (from_type2, from_type1)) + return 1; + else if (is_properly_derived_from (from_type1, from_type2)) + return -1; + } + } + + /* [over.ics.rank] + + --S1 and S2 differ only in their qualification conversion and yield + similar types T1 and T2 (_conv.qual_), respectively, and the cv- + qualification signature of type T1 is a proper subset of the cv- + qualification signature of type T2 */ + if (ics1->kind == ck_qual + && ics2->kind == ck_qual + && same_type_p (from_type1, from_type2)) + return comp_cv_qual_signature (to_type1, to_type2); + + /* [over.ics.rank] + + --S1 and S2 are reference bindings (_dcl.init.ref_), and the + types to which the references refer are the same type except for + top-level cv-qualifiers, and the type to which the reference + initialized by S2 refers is more cv-qualified than the type to + which the reference initialized by S1 refers */ + + if (target_type1 && target_type2 + && same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2)) + return comp_cv_qualification (target_type2, target_type1); + + /* Neither conversion sequence is better than the other. */ + return 0; +} + +/* The source type for this standard conversion sequence. */ + +static tree +source_type (conversion *t) +{ + for (;; t = t->u.next) + { + if (t->kind == ck_user + || t->kind == ck_ambig + || t->kind == ck_identity) + return t->type; + } + gcc_unreachable (); +} + +/* Note a warning about preferring WINNER to LOSER. We do this by storing + a pointer to LOSER and re-running joust to produce the warning if WINNER + is actually used. */ + +static void +add_warning (struct z_candidate *winner, struct z_candidate *loser) +{ + candidate_warning *cw = (candidate_warning *) + conversion_obstack_alloc (sizeof (candidate_warning)); + cw->loser = loser; + cw->next = winner->warnings; + winner->warnings = cw; +} + +/* Compare two candidates for overloading as described in + [over.match.best]. Return values: + + 1: cand1 is better than cand2 + -1: cand2 is better than cand1 + 0: cand1 and cand2 are indistinguishable */ + +static int +joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn) +{ + int winner = 0; + int off1 = 0, off2 = 0; + size_t i; + size_t len; + + /* Candidates that involve bad conversions are always worse than those + that don't. */ + if (cand1->viable > cand2->viable) + return 1; + if (cand1->viable < cand2->viable) + return -1; + + /* If we have two pseudo-candidates for conversions to the same type, + or two candidates for the same function, arbitrarily pick one. */ + if (cand1->fn == cand2->fn + && (IS_TYPE_OR_DECL_P (cand1->fn))) + return 1; + + /* a viable function F1 + is defined to be a better function than another viable function F2 if + for all arguments i, ICSi(F1) is not a worse conversion sequence than + ICSi(F2), and then */ + + /* for some argument j, ICSj(F1) is a better conversion sequence than + ICSj(F2) */ + + /* For comparing static and non-static member functions, we ignore + the implicit object parameter of the non-static function. The + standard says to pretend that the static function has an object + parm, but that won't work with operator overloading. */ + len = cand1->num_convs; + if (len != cand2->num_convs) + { + int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn); + int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn); + + gcc_assert (static_1 != static_2); + + if (static_1) + off2 = 1; + else + { + off1 = 1; + --len; + } + } + + for (i = 0; i < len; ++i) + { + conversion *t1 = cand1->convs[i + off1]; + conversion *t2 = cand2->convs[i + off2]; + int comp = compare_ics (t1, t2); + + if (comp != 0) + { + if (warn_sign_promo + && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2) + == cr_std + cr_promotion) + && t1->kind == ck_std + && t2->kind == ck_std + && TREE_CODE (t1->type) == INTEGER_TYPE + && TREE_CODE (t2->type) == INTEGER_TYPE + && (TYPE_PRECISION (t1->type) + == TYPE_PRECISION (t2->type)) + && (TYPE_UNSIGNED (t1->u.next->type) + || (TREE_CODE (t1->u.next->type) + == ENUMERAL_TYPE))) + { + tree type = t1->u.next->type; + tree type1, type2; + struct z_candidate *w, *l; + if (comp > 0) + type1 = t1->type, type2 = t2->type, + w = cand1, l = cand2; + else + type1 = t2->type, type2 = t1->type, + w = cand2, l = cand1; + + if (warn) + { + warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT", + type, type1, type2); + warning (OPT_Wsign_promo, " in call to %qD", w->fn); + } + else + add_warning (w, l); + } + + if (winner && comp != winner) + { + winner = 0; + goto tweak; + } + winner = comp; + } + } + + /* warn about confusing overload resolution for user-defined conversions, + either between a constructor and a conversion op, or between two + conversion ops. */ + if (winner && warn_conversion && cand1->second_conv + && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn)) + && winner != compare_ics (cand1->second_conv, cand2->second_conv)) + { + struct z_candidate *w, *l; + bool give_warning = false; + + if (winner == 1) + w = cand1, l = cand2; + else + w = cand2, l = cand1; + + /* We don't want to complain about `X::operator T1 ()' + beating `X::operator T2 () const', when T2 is a no less + cv-qualified version of T1. */ + if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn) + && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn)) + { + tree t = TREE_TYPE (TREE_TYPE (l->fn)); + tree f = TREE_TYPE (TREE_TYPE (w->fn)); + + if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t)) + { + t = TREE_TYPE (t); + f = TREE_TYPE (f); + } + if (!comp_ptr_ttypes (t, f)) + give_warning = true; + } + else + give_warning = true; + + if (!give_warning) + /*NOP*/; + else if (warn) + { + tree source = source_type (w->convs[0]); + if (! DECL_CONSTRUCTOR_P (w->fn)) + source = TREE_TYPE (source); + warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn); + warning (OPT_Wconversion, " for conversion from %qT to %qT", + source, w->second_conv->type); + inform (" because conversion sequence for the argument is better"); + } + else + add_warning (w, l); + } + + if (winner) + return winner; + + /* or, if not that, + F1 is a non-template function and F2 is a template function + specialization. */ + + if (!cand1->template_decl && cand2->template_decl) + return 1; + else if (cand1->template_decl && !cand2->template_decl) + return -1; + + /* or, if not that, + F1 and F2 are template functions and the function template for F1 is + more specialized than the template for F2 according to the partial + ordering rules. */ + + if (cand1->template_decl && cand2->template_decl) + { + winner = more_specialized_fn + (TI_TEMPLATE (cand1->template_decl), + TI_TEMPLATE (cand2->template_decl), + /* [temp.func.order]: The presence of unused ellipsis and default + arguments has no effect on the partial ordering of function + templates. add_function_candidate() will not have + counted the "this" argument for constructors. */ + cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn)); + if (winner) + return winner; + } + + /* or, if not that, + the context is an initialization by user-defined conversion (see + _dcl.init_ and _over.match.user_) and the standard conversion + sequence from the return type of F1 to the destination type (i.e., + the type of the entity being initialized) is a better conversion + sequence than the standard conversion sequence from the return type + of F2 to the destination type. */ + + if (cand1->second_conv) + { + winner = compare_ics (cand1->second_conv, cand2->second_conv); + if (winner) + return winner; + } + + /* Check whether we can discard a builtin candidate, either because we + have two identical ones or matching builtin and non-builtin candidates. + + (Pedantically in the latter case the builtin which matched the user + function should not be added to the overload set, but we spot it here. + + [over.match.oper] + ... the builtin candidates include ... + - do not have the same parameter type list as any non-template + non-member candidate. */ + + if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE + || TREE_CODE (cand2->fn) == IDENTIFIER_NODE) + { + for (i = 0; i < len; ++i) + if (!same_type_p (cand1->convs[i]->type, + cand2->convs[i]->type)) + break; + if (i == cand1->num_convs) + { + if (cand1->fn == cand2->fn) + /* Two built-in candidates; arbitrarily pick one. */ + return 1; + else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE) + /* cand1 is built-in; prefer cand2. */ + return -1; + else + /* cand2 is built-in; prefer cand1. */ + return 1; + } + } + + /* If the two functions are the same (this can happen with declarations + in multiple scopes and arg-dependent lookup), arbitrarily choose one. */ + if (DECL_P (cand1->fn) && DECL_P (cand2->fn) + && equal_functions (cand1->fn, cand2->fn)) + return 1; + +tweak: + + /* Extension: If the worst conversion for one candidate is worse than the + worst conversion for the other, take the first. */ + if (!pedantic) + { + conversion_rank rank1 = cr_identity, rank2 = cr_identity; + struct z_candidate *w = 0, *l = 0; + + for (i = 0; i < len; ++i) + { + if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1) + rank1 = CONVERSION_RANK (cand1->convs[i+off1]); + if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2) + rank2 = CONVERSION_RANK (cand2->convs[i + off2]); + } + if (rank1 < rank2) + winner = 1, w = cand1, l = cand2; + if (rank1 > rank2) + winner = -1, w = cand2, l = cand1; + if (winner) + { + if (warn) + { + pedwarn ("\ +ISO C++ says that these are ambiguous, even \ +though the worst conversion for the first is better than \ +the worst conversion for the second:"); + print_z_candidate (_("candidate 1:"), w); + print_z_candidate (_("candidate 2:"), l); + } + else + add_warning (w, l); + return winner; + } + } + + gcc_assert (!winner); + return 0; +} + +/* Given a list of candidates for overloading, find the best one, if any. + This algorithm has a worst case of O(2n) (winner is last), and a best + case of O(n/2) (totally ambiguous); much better than a sorting + algorithm. */ + +static struct z_candidate * +tourney (struct z_candidate *candidates) +{ + struct z_candidate *champ = candidates, *challenger; + int fate; + int champ_compared_to_predecessor = 0; + + /* Walk through the list once, comparing each current champ to the next + candidate, knocking out a candidate or two with each comparison. */ + + for (challenger = champ->next; challenger; ) + { + fate = joust (champ, challenger, 0); + if (fate == 1) + challenger = challenger->next; + else + { + if (fate == 0) + { + champ = challenger->next; + if (champ == 0) + return NULL; + champ_compared_to_predecessor = 0; + } + else + { + champ = challenger; + champ_compared_to_predecessor = 1; + } + + challenger = champ->next; + } + } + + /* Make sure the champ is better than all the candidates it hasn't yet + been compared to. */ + + for (challenger = candidates; + challenger != champ + && !(champ_compared_to_predecessor && challenger->next == champ); + challenger = challenger->next) + { + fate = joust (champ, challenger, 0); + if (fate != 1) + return NULL; + } + + return champ; +} + +/* Returns nonzero if things of type FROM can be converted to TO. */ + +bool +can_convert (tree to, tree from) +{ + return can_convert_arg (to, from, NULL_TREE, LOOKUP_NORMAL); +} + +/* Returns nonzero if ARG (of type FROM) can be converted to TO. */ + +bool +can_convert_arg (tree to, tree from, tree arg, int flags) +{ + conversion *t; + void *p; + bool ok_p; + + /* Get the high-water mark for the CONVERSION_OBSTACK. */ + p = conversion_obstack_alloc (0); + + t = implicit_conversion (to, from, arg, /*c_cast_p=*/false, + flags); + ok_p = (t && !t->bad_p); + + /* Free all the conversions we allocated. */ + obstack_free (&conversion_obstack, p); + + return ok_p; +} + +/* Like can_convert_arg, but allows dubious conversions as well. */ + +bool +can_convert_arg_bad (tree to, tree from, tree arg) +{ + conversion *t; + void *p; + + /* Get the high-water mark for the CONVERSION_OBSTACK. */ + p = conversion_obstack_alloc (0); + /* Try to perform the conversion. */ + t = implicit_conversion (to, from, arg, /*c_cast_p=*/false, + LOOKUP_NORMAL); + /* Free all the conversions we allocated. */ + obstack_free (&conversion_obstack, p); + + return t != NULL; +} + +/* Convert EXPR to TYPE. Return the converted expression. + + Note that 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. */ + +tree +perform_implicit_conversion (tree type, tree expr) +{ + conversion *conv; + void *p; + + if (error_operand_p (expr)) + return error_mark_node; + + /* Get the high-water mark for the CONVERSION_OBSTACK. */ + p = conversion_obstack_alloc (0); + + conv = implicit_conversion (type, TREE_TYPE (expr), expr, + /*c_cast_p=*/false, + LOOKUP_NORMAL); + if (!conv) + { + error ("could not convert %qE to %qT", expr, type); + expr = error_mark_node; + } + else if (processing_template_decl) + { + /* In a template, we are only concerned about determining the + type of non-dependent expressions, so we do not have to + perform the actual conversion. */ + if (TREE_TYPE (expr) != type) + expr = build_nop (type, expr); + } + else + expr = convert_like (conv, expr); + + /* Free all the conversions we allocated. */ + obstack_free (&conversion_obstack, p); + + return expr; +} + +/* Convert EXPR to TYPE (as a direct-initialization) if that is + permitted. If the conversion is valid, the converted expression is + returned. Otherwise, NULL_TREE is returned, except in the case + that TYPE is a class type; in that case, an error is issued. If + C_CAST_P is true, then this direction initialization is taking + place as part of a static_cast being attempted as part of a C-style + cast. */ + +tree +perform_direct_initialization_if_possible (tree type, + tree expr, + bool c_cast_p) +{ + conversion *conv; + void *p; + + if (type == error_mark_node || error_operand_p (expr)) + return error_mark_node; + /* [dcl.init] + + If the destination type is a (possibly cv-qualified) class type: + + -- If the initialization is direct-initialization ..., + constructors are considered. ... If no constructor applies, or + the overload resolution is ambiguous, the initialization is + ill-formed. */ + if (CLASS_TYPE_P (type)) + { + expr = build_special_member_call (NULL_TREE, complete_ctor_identifier, + build_tree_list (NULL_TREE, expr), + type, LOOKUP_NORMAL); + return build_cplus_new (type, expr); + } + + /* Get the high-water mark for the CONVERSION_OBSTACK. */ + p = conversion_obstack_alloc (0); + + conv = implicit_conversion (type, TREE_TYPE (expr), expr, + c_cast_p, + LOOKUP_NORMAL); + if (!conv || conv->bad_p) + expr = NULL_TREE; + else + expr = convert_like_real (conv, expr, NULL_TREE, 0, 0, + /*issue_conversion_warnings=*/false, + c_cast_p); + + /* Free all the conversions we allocated. */ + obstack_free (&conversion_obstack, p); + + return expr; +} + +/* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference + is being bound to a temporary. Create and return a new VAR_DECL + with the indicated TYPE; this variable will store the value to + which the reference is bound. */ + +tree +make_temporary_var_for_ref_to_temp (tree decl, tree type) +{ + tree var; + + /* Create the variable. */ + var = create_temporary_var (type); + + /* Register the variable. */ + if (TREE_STATIC (decl)) + { + /* Namespace-scope or local static; give it a mangled name. */ + tree name; + + TREE_STATIC (var) = 1; + name = mangle_ref_init_variable (decl); + DECL_NAME (var) = name; + SET_DECL_ASSEMBLER_NAME (var, name); + var = pushdecl_top_level (var); + } + else + /* Create a new cleanup level if necessary. */ + maybe_push_cleanup_level (type); + + return var; +} + +/* Convert EXPR to the indicated reference TYPE, in a way suitable for + initializing a variable of that TYPE. If DECL is non-NULL, it is + the VAR_DECL being initialized with the EXPR. (In that case, the + type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must + also be non-NULL, and with *CLEANUP initialized to NULL. Upon + return, if *CLEANUP is no longer NULL, it will be an expression + that should be pushed as a cleanup after the returned expression + is used to initialize DECL. + + Return the converted expression. */ + +tree +initialize_reference (tree type, tree expr, tree decl, tree *cleanup) +{ + conversion *conv; + void *p; + + if (type == error_mark_node || error_operand_p (expr)) + return error_mark_node; + + /* Get the high-water mark for the CONVERSION_OBSTACK. */ + p = conversion_obstack_alloc (0); + + conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false, + LOOKUP_NORMAL); + if (!conv || conv->bad_p) + { + if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST) + && !real_lvalue_p (expr)) + error ("invalid initialization of non-const reference of " + "type %qT from a temporary of type %qT", + type, TREE_TYPE (expr)); + else + error ("invalid initialization of reference of type " + "%qT from expression of type %qT", type, + TREE_TYPE (expr)); + return error_mark_node; + } + + /* If DECL is non-NULL, then this special rule applies: + + [class.temporary] + + The temporary to which the reference is bound or the temporary + that is the complete object to which the reference is bound + persists for the lifetime of the reference. + + The temporaries created during the evaluation of the expression + initializing the reference, except the temporary to which the + reference is bound, are destroyed at the end of the + full-expression in which they are created. + + In that case, we store the converted expression into a new + VAR_DECL in a new scope. + + However, we want to be careful not to create temporaries when + they are not required. For example, given: + + struct B {}; + struct D : public B {}; + D f(); + const B& b = f(); + + there is no need to copy the return value from "f"; we can just + extend its lifetime. Similarly, given: + + struct S {}; + struct T { operator S(); }; + T t; + const S& s = t; + + we can extend the lifetime of the return value of the conversion + operator. */ + gcc_assert (conv->kind == ck_ref_bind); + if (decl) + { + tree var; + tree base_conv_type; + + /* Skip over the REF_BIND. */ + conv = conv->u.next; + /* If the next conversion is a BASE_CONV, skip that too -- but + remember that the conversion was required. */ + if (conv->kind == ck_base) + { + if (conv->check_copy_constructor_p) + check_constructor_callable (TREE_TYPE (expr), expr); + base_conv_type = conv->type; + conv = conv->u.next; + } + else + base_conv_type = NULL_TREE; + /* Perform the remainder of the conversion. */ + expr = convert_like_real (conv, expr, + /*fn=*/NULL_TREE, /*argnum=*/0, + /*inner=*/-1, + /*issue_conversion_warnings=*/true, + /*c_cast_p=*/false); + if (error_operand_p (expr)) + expr = error_mark_node; + else + { + if (!real_lvalue_p (expr)) + { + tree init; + tree type; + + /* Create the temporary variable. */ + type = TREE_TYPE (expr); + var = make_temporary_var_for_ref_to_temp (decl, type); + layout_decl (var, 0); + /* If the rvalue is the result of a function call it will be + a TARGET_EXPR. If it is some other construct (such as a + member access expression where the underlying object is + itself the result of a function call), turn it into a + TARGET_EXPR here. It is important that EXPR be a + TARGET_EXPR below since otherwise the INIT_EXPR will + attempt to make a bitwise copy of EXPR to initialize + VAR. */ + if (TREE_CODE (expr) != TARGET_EXPR) + expr = get_target_expr (expr); + /* Create the INIT_EXPR that will initialize the temporary + variable. */ + init = build2 (INIT_EXPR, type, var, expr); + if (at_function_scope_p ()) + { + add_decl_expr (var); + *cleanup = cxx_maybe_build_cleanup (var); + + /* We must be careful to destroy the temporary only + after its initialization has taken place. If the + initialization throws an exception, then the + destructor should not be run. We cannot simply + transform INIT into something like: + + (INIT, ({ CLEANUP_STMT; })) + + because emit_local_var always treats the + initializer as a full-expression. Thus, the + destructor would run too early; it would run at the + end of initializing the reference variable, rather + than at the end of the block enclosing the + reference variable. + + The solution is to pass back a cleanup expression + which the caller is responsible for attaching to + the statement tree. */ + } + else + { + rest_of_decl_compilation (var, /*toplev=*/1, at_eof); + if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)) + static_aggregates = tree_cons (NULL_TREE, var, + static_aggregates); + } + /* Use its address to initialize the reference variable. */ + expr = build_address (var); + if (base_conv_type) + expr = convert_to_base (expr, + build_pointer_type (base_conv_type), + /*check_access=*/true, + /*nonnull=*/true); + expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr); + } + else + /* Take the address of EXPR. */ + expr = build_unary_op (ADDR_EXPR, expr, 0); + /* If a BASE_CONV was required, perform it now. */ + if (base_conv_type) + expr = (perform_implicit_conversion + (build_pointer_type (base_conv_type), expr)); + expr = build_nop (type, expr); + } + } + else + /* Perform the conversion. */ + expr = convert_like (conv, expr); + + /* Free all the conversions we allocated. */ + obstack_free (&conversion_obstack, p); + + return expr; +} + +#include "gt-cp-call.h" |