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Diffstat (limited to 'gcc-4.4.3/gcc/ada/sem_elab.ads')
-rw-r--r-- | gcc-4.4.3/gcc/ada/sem_elab.ads | 159 |
1 files changed, 0 insertions, 159 deletions
diff --git a/gcc-4.4.3/gcc/ada/sem_elab.ads b/gcc-4.4.3/gcc/ada/sem_elab.ads deleted file mode 100644 index 7b85b6f88..000000000 --- a/gcc-4.4.3/gcc/ada/sem_elab.ads +++ /dev/null @@ -1,159 +0,0 @@ ------------------------------------------------------------------------------- --- -- --- GNAT COMPILER COMPONENTS -- --- -- --- S E M _ E L A B -- --- -- --- S p e c -- --- -- --- Copyright (C) 1997-2008, Free Software Foundation, Inc. -- --- -- --- GNAT is free software; you can redistribute it and/or modify it under -- --- terms of the GNU General Public License as published by the Free Soft- -- --- ware Foundation; either version 3, or (at your option) any later ver- -- --- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- --- OUT 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 distributed with GNAT; see file COPYING3. If not, go to -- --- http://www.gnu.org/licenses for a complete copy of the license. -- --- -- --- GNAT was originally developed by the GNAT team at New York University. -- --- Extensive contributions were provided by Ada Core Technologies Inc. -- --- -- ------------------------------------------------------------------------------- - --- This package contains the routines used to deal with issuing warnings --- for cases of calls that may require warnings about possible access --- before elaboration. - -with Types; use Types; - -package Sem_Elab is - - ----------------------------- - -- Description of Approach -- - ----------------------------- - - -- Every non-static call that is encountered by Sem_Res results in - -- a call to Check_Elab_Call, with N being the call node, and Outer - -- set to its default value of True. - - -- The goal of Check_Elab_Call is to determine whether or not the - -- call in question can generate an access before elaboration - -- error (raising Program_Error) either by directly calling a - -- subprogram whose body has not yet been elaborated, or indirectly, - -- by calling a subprogram whose body has been elaborated, but which - -- contains a call to such a subprogram. - - -- The only calls that we need to look at at the outer level are - -- calls that occur in elaboration code. There are two cases. The - -- call can be at the outer level of elaboration code, or it can - -- be within another unit, e.g. the elaboration code of a subprogram. - - -- In the case of an elaboration call at the outer level, we must - -- trace all calls to outer level routines either within the current - -- unit or to other units that are with'ed. For calls within the - -- current unit, we can determine if the body has been elaborated - -- or not, and if it has not, then a warning is generated. - - -- Note that there are two subcases. If the original call directly - -- calls a subprogram whose body has not been elaborated, then we - -- know that an ABE will take place, and we replace the call by - -- a raise of Program_Error. If the call is indirect, then we don't - -- know that the PE will be raised, since the call might be guarded - -- by a conditional. In this case we set Do_Elab_Check on the call - -- so that a dynamic check is generated, and output a warning. - - -- For calls to a subprogram in a with'ed unit, we require that - -- a pragma Elaborate_All or pragma Elaborate be present, or that - -- the referenced unit have a pragma Preelaborate, pragma Pure, or - -- pragma Elaborate_Body. If none of these conditions is met, then - -- a warning is generated that a pragma Elaborate_All may be needed. - - -- For the case of an elaboration call at some inner level, we are - -- interested in tracing only calls to subprograms at the same level, - -- i.e. those that can be called during elaboration. Any calls to - -- outer level routines cannot cause ABE's as a result of the original - -- call (there might be an outer level call to the subprogram from - -- outside that causes the ABE, but that gets analyzed separately). - - -- Note that we never trace calls to inner level subprograms, since - -- these cannot result in ABE's unless there is an elaboration problem - -- at a lower level, which will be separately detected. - - -- Note on pragma Elaborate. The checking here assumes that a pragma - -- Elaborate on a with'ed unit guarantees that subprograms within the - -- unit can be called without causing an ABE. This is not in fact the - -- case since pragma Elaborate does not guarantee the transitive - -- coverage guaranteed by Elaborate_All. However, we leave this issue - -- up to the binder, which has generates warnings if there are possible - -- problems in the use of pragma Elaborate. - - -------------------------------------- - -- Instantiation Elaboration Errors -- - -------------------------------------- - - -- A special case arises when an instantiation appears in a context - -- that is known to be before the body is elaborated, e.g. - - -- generic package x is ... - -- ... - -- package xx is new x; - -- ... - -- package body x is ... - - -- In this situation it is certain that an elaboration error will - -- occur, and an unconditional raise Program_Error statement is - -- inserted before the instantiation, and a warning generated. - - -- The problem is that in this case we have no place to put the - -- body of the instantiation. We can't put it in the normal place, - -- because it is too early, and will cause errors to occur as a - -- result of referencing entities before they are declared. - - -- Our approach in this case is simply to avoid creating the body - -- of the instantiation in such a case. The instantiation spec is - -- modified to include dummy bodies for all subprograms, so that - -- the resulting code does not contain subprogram specs with no - -- corresponding bodies. - - procedure Check_Elab_Call (N : Node_Id; Outer_Scope : Entity_Id := Empty); - -- Check a call for possible elaboration problems. The node N is either - -- an N_Function_Call or N_Procedure_Call_Statement node. The Outer_Scope - -- argument indicates whether this is an outer level call from Sem_Res - -- (Outer_Scope set to Empty), or an internal recursive call (Outer_Scope - -- set to entity of outermost call, see body). - - procedure Check_Elab_Calls; - -- Not all the processing for Check_Elab_Call can be done at the time - -- of calls to Check_Elab_Call. This is because for internal calls, we - -- need to wait to complete the check until all generic bodies have been - -- instantiated. The Check_Elab_Calls procedure cleans up these waiting - -- checks. It is called once after the completion of instantiation. - - procedure Check_Elab_Assign (N : Node_Id); - -- N is either the left side of an assignment, or a procedure argument for - -- a mode OUT or IN OUT formal. This procedure checks for a possible case - -- of access to an entity from elaboration code before the entity has been - -- initialized, and issues appropriate warnings. - - procedure Check_Elab_Instantiation - (N : Node_Id; - Outer_Scope : Entity_Id := Empty); - -- Check an instantiation for possible elaboration problems. N is an - -- instantiation node (N_Package_Instantiation, N_Function_Instantiation, - -- or N_Procedure_Instantiation), and Outer_Scope indicates if this is - -- an outer level call from Sem_Ch12 (Outer_Scope set to Empty), or an - -- internal recursive call (Outer_Scope set to scope of outermost call, - -- see body for further details). The returned value is relevant only - -- for an outer level call, and is set to False if an elaboration error - -- is bound to occur on the instantiation, and True otherwise. This is - -- used by the caller to signal that the body of the instance should - -- not be generated (see detailed description in body). - - procedure Check_Task_Activation (N : Node_Id); - -- at the point at which tasks are activated in a package body, check - -- that the bodies of the tasks are elaborated. - -end Sem_Elab; |