1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1997-2004 Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Debug; use Debug;
30 with Einfo; use Einfo;
31 with Elists; use Elists;
32 with Errout; use Errout;
33 with Exp_Tss; use Exp_Tss;
34 with Exp_Util; use Exp_Util;
35 with Expander; use Expander;
36 with Fname; use Fname;
38 with Lib.Load; use Lib.Load;
39 with Namet; use Namet;
40 with Nlists; use Nlists;
41 with Nmake; use Nmake;
43 with Output; use Output;
44 with Restrict; use Restrict;
45 with Rident; use Rident;
47 with Sem_Cat; use Sem_Cat;
48 with Sem_Ch7; use Sem_Ch7;
49 with Sem_Ch8; use Sem_Ch8;
50 with Sem_Res; use Sem_Res;
51 with Sem_Util; use Sem_Util;
52 with Sinfo; use Sinfo;
53 with Sinput; use Sinput;
54 with Snames; use Snames;
55 with Stand; use Stand;
57 with Tbuild; use Tbuild;
58 with Uname; use Uname;
60 package body Sem_Elab is
62 -- The following table records the recursive call chain for output
63 -- in the Output routine. Each entry records the call node and the
64 -- entity of the called routine. The number of entries in the table
65 -- (i.e. the value of Elab_Call.Last) indicates the current depth
66 -- of recursion and is used to identify the outer level.
68 type Elab_Call_Entry is record
73 package Elab_Call is new Table.Table (
74 Table_Component_Type => Elab_Call_Entry,
75 Table_Index_Type => Int,
78 Table_Increment => 100,
79 Table_Name => "Elab_Call");
81 -- This table is initialized at the start of each outer level call.
82 -- It holds the entities for all subprograms that have been examined
83 -- for this particular outer level call, and is used to prevent both
84 -- infinite recursion, and useless reanalysis of bodies already seen
86 package Elab_Visited is new Table.Table (
87 Table_Component_Type => Entity_Id,
88 Table_Index_Type => Int,
91 Table_Increment => 100,
92 Table_Name => "Elab_Visited");
94 -- This table stores calls to Check_Internal_Call that are delayed
95 -- until all generics are instantiated, and in particular that all
96 -- generic bodies have been inserted. We need to delay, because we
97 -- need to be able to look through the inserted bodies.
99 type Delay_Element is record
101 -- The parameter N from the call to Check_Internal_Call. Note that
102 -- this node may get rewritten over the delay period by expansion
103 -- in the call case (but not in the instantiation case).
106 -- The parameter E from the call to Check_Internal_Call
108 Orig_Ent : Entity_Id;
109 -- The parameter Orig_Ent from the call to Check_Internal_Call
112 -- The current scope of the call. This is restored when we complete
113 -- the delayed call, so that we do this in the right scope.
115 From_Elab_Code : Boolean;
116 -- Save indication of whether this call is from elaboration code
118 Outer_Scope : Entity_Id;
119 -- Save scope of outer level call
123 package Delay_Check is new Table.Table (
124 Table_Component_Type => Delay_Element,
125 Table_Index_Type => Int,
126 Table_Low_Bound => 1,
127 Table_Initial => 1000,
128 Table_Increment => 100,
129 Table_Name => "Delay_Check");
132 -- Top level scope of current scope. We need to compute this only
133 -- once at the outer level, i.e. for a call to Check_Elab_Call from
134 -- outside this unit.
136 Outer_Level_Sloc : Source_Ptr;
137 -- Save Sloc value for outer level call node for comparisons of source
138 -- locations. A body is too late if it appears after the *outer* level
139 -- call, not the particular call that is being analyzed.
141 From_Elab_Code : Boolean;
142 -- This flag shows whether the outer level call currently being examined
143 -- is or is not in elaboration code. We are only interested in calls to
144 -- routines in other units if this flag is True.
146 In_Task_Activation : Boolean := False;
147 -- This flag indicates whether we are performing elaboration checks on
148 -- task procedures, at the point of activation. If true, we do not trace
149 -- internal calls in these procedures, because all local bodies are known
152 Delaying_Elab_Checks : Boolean := True;
153 -- This is set True till the compilation is complete, including the
154 -- insertion of all instance bodies. Then when Check_Elab_Calls is
155 -- called, the delay table is used to make the delayed calls and
156 -- this flag is reset to False, so that the calls are processed
158 -----------------------
159 -- Local Subprograms --
160 -----------------------
162 -- Note: Outer_Scope in all these calls represents the scope of
163 -- interest of the outer level call. If it is set to Standard_Standard,
164 -- then it means the outer level call was at elaboration level, and that
165 -- thus all calls are of interest. If it was set to some other scope,
166 -- then the original call was an inner call, and we are not interested
167 -- in calls that go outside this scope.
169 procedure Check_A_Call
172 Outer_Scope : Entity_Id;
173 Inter_Unit_Only : Boolean;
174 Generate_Warnings : Boolean := True);
175 -- This is the internal recursive routine that is called to check for
176 -- a possible elaboration error. The argument N is a subprogram call
177 -- or generic instantiation to be checked, and E is the entity of
178 -- the called subprogram, or instantiated generic unit. The flag
179 -- Outer_Scope is the outer level scope for the original call.
180 -- Inter_Unit_Only is set if the call is only to be checked in the
181 -- case where it is to another unit (and skipped if within a unit).
182 -- Generate_Warnings is set to False to suppress warning messages
183 -- about missing pragma Elaborate_All's. These messages are not
184 -- wanted for inner calls in the dynamic model.
186 procedure Check_Bad_Instantiation (N : Node_Id);
187 -- N is a node for an instantiation (if called with any other node kind,
188 -- Check_Bad_Instantiation ignores the call). This subprogram checks for
189 -- the special case of a generic instantiation of a generic spec in the
190 -- same declarative part as the instantiation where a body is present and
191 -- has not yet been seen. This is an obvious error, but needs to be checked
192 -- specially at the time of the instantiation, since it is a case where we
193 -- cannot insert the body anywhere. If this case is detected, warnings are
194 -- generated, and a raise of Program_Error is inserted. In addition any
195 -- subprograms in the generic spec are stubbed, and the Bad_Instantiation
196 -- flag is set on the instantiation node. The caller in Sem_Ch12 uses this
197 -- flag as an indication that no attempt should be made to insert an
200 procedure Check_Internal_Call
203 Outer_Scope : Entity_Id;
204 Orig_Ent : Entity_Id);
205 -- N is a function call or procedure statement call node and E is
206 -- the entity of the called function, which is within the current
207 -- compilation unit (where subunits count as part of the parent).
208 -- This call checks if this call, or any call within any accessed
209 -- body could cause an ABE, and if so, outputs a warning. Orig_Ent
210 -- differs from E only in the case of renamings, and points to the
211 -- original name of the entity. This is used for error messages.
212 -- Outer_Scope is the outer level scope for the original call.
214 procedure Check_Internal_Call_Continue
217 Outer_Scope : Entity_Id;
218 Orig_Ent : Entity_Id);
219 -- The processing for Check_Internal_Call is divided up into two phases,
220 -- and this represents the second phase. The second phase is delayed if
221 -- Delaying_Elab_Calls is set to True. In this delayed case, the first
222 -- phase makes an entry in the Delay_Check table, which is processed
223 -- when Check_Elab_Calls is called. N, E and Orig_Ent are as for the call
224 -- to Check_Internal_Call. Outer_Scope is the outer level scope for
225 -- the original call.
227 function Has_Generic_Body (N : Node_Id) return Boolean;
228 -- N is a generic package instantiation node, and this routine determines
229 -- if this package spec does in fact have a generic body. If so, then
230 -- True is returned, otherwise False. Note that this is not at all the
231 -- same as checking if the unit requires a body, since it deals with
232 -- the case of optional bodies accurately (i.e. if a body is optional,
233 -- then it looks to see if a body is actually present). Note: this
234 -- function can only do a fully correct job if in generating code mode
235 -- where all bodies have to be present. If we are operating in semantics
236 -- check only mode, then in some cases of optional bodies, a result of
237 -- False may incorrectly be given. In practice this simply means that
238 -- some cases of warnings for incorrect order of elaboration will only
239 -- be given when generating code, which is not a big problem (and is
240 -- inevitable, given the optional body semantics of Ada).
242 procedure Insert_Elab_Check (N : Node_Id; C : Node_Id := Empty);
243 -- Given code for an elaboration check (or unconditional raise if
244 -- the check is not needed), inserts the code in the appropriate
245 -- place. N is the call or instantiation node for which the check
246 -- code is required. C is the test whose failure triggers the raise.
248 procedure Output_Calls (N : Node_Id);
249 -- Outputs chain of calls stored in the Elab_Call table. The caller
250 -- has already generated the main warning message, so the warnings
251 -- generated are all continuation messages. The argument is the
252 -- call node at which the messages are to be placed.
254 function Same_Elaboration_Scope (Scop1, Scop2 : Entity_Id) return Boolean;
255 -- Given two scopes, determine whether they are the same scope from an
256 -- elaboration point of view, i.e. packages and blocks are ignored.
258 procedure Set_C_Scope;
259 -- On entry C_Scope is set to some scope. On return, C_Scope is reset
260 -- to be the enclosing compilation unit of this scope.
262 function Spec_Entity (E : Entity_Id) return Entity_Id;
263 -- Given a compilation unit entity, if it is a spec entity, it is
264 -- returned unchanged. If it is a body entity, then the spec for
265 -- the corresponding spec is returned
267 procedure Supply_Bodies (N : Node_Id);
268 -- Given a node, N, that is either a subprogram declaration or a package
269 -- declaration, this procedure supplies dummy bodies for the subprogram
270 -- or for all subprograms in the package. If the given node is not one
271 -- of these two possibilities, then Supply_Bodies does nothing. The
272 -- dummy body is supplied by setting the subprogram to be Imported with
273 -- convention Stubbed.
275 procedure Supply_Bodies (L : List_Id);
276 -- Calls Supply_Bodies for all elements of the given list L.
278 function Within (E1, E2 : Entity_Id) return Boolean;
279 -- Given two scopes E1 and E2, returns True if E1 is equal to E2, or
280 -- is one of its contained scopes, False otherwise.
282 function Within_Elaborate_All (E : Entity_Id) return Boolean;
283 -- Before emitting a warning on a scope E for a missing elaborate_all,
284 -- check whether E may be in the context of a directly visible unit
285 -- U to which the pragma applies. This prevents spurious warnings when
286 -- the called entity is renamed within U.
292 procedure Check_A_Call
295 Outer_Scope : Entity_Id;
296 Inter_Unit_Only : Boolean;
297 Generate_Warnings : Boolean := True)
299 Loc : constant Source_Ptr := Sloc (N);
304 -- Top level scope of entity for called subprogram. This
305 -- value includes following renamings and derivations, so
306 -- this scope can be in a non-visible unit. This is the
307 -- scope that is to be investigated to see whether an
308 -- elaboration check is required.
311 -- Top level scope of directly called entity for subprogram.
312 -- This differs from E_Scope in the case where renamings or
313 -- derivations are involved, since it does not follow these
314 -- links, thus W_Scope is always in a visible unit. This is
315 -- the scope for the Elaborate_All if one is needed.
317 Body_Acts_As_Spec : Boolean;
318 -- Set to true if call is to body acting as spec (no separate spec)
320 Inst_Case : constant Boolean := Nkind (N) in N_Generic_Instantiation;
321 -- Indicates if we have instantiation case
323 Caller_Unit_Internal : Boolean;
324 Callee_Unit_Internal : Boolean;
326 Inst_Caller : Source_Ptr;
327 Inst_Callee : Source_Ptr;
329 Unit_Caller : Unit_Number_Type;
330 Unit_Callee : Unit_Number_Type;
332 Cunit_SC : Boolean := False;
333 -- Set to suppress dynamic elaboration checks where one of the
334 -- enclosing scopes has Elaboration_Checks_Suppressed set, or else
335 -- if a pragma Elaborate (_All) applies to that scope, in which case
336 -- warnings on the scope are also suppressed. For the internal case,
337 -- we ignore this flag.
340 -- If the call is known to be within a local Suppress Elaboration
341 -- pragma, nothing to check. This can happen in task bodies.
343 if (Nkind (N) = N_Function_Call
344 or else Nkind (N) = N_Procedure_Call_Statement)
345 and then No_Elaboration_Check (N)
350 -- Go to parent for derived subprogram, or to original subprogram
351 -- in the case of a renaming (Alias covers both these cases)
355 if (Suppress_Elaboration_Warnings (Ent)
356 or else Elaboration_Checks_Suppressed (Ent))
357 and then (Inst_Case or else No (Alias (Ent)))
362 -- Nothing to do for imported entities,
364 if Is_Imported (Ent) then
368 exit when Inst_Case or else No (Alias (Ent));
372 Decl := Unit_Declaration_Node (Ent);
374 if Nkind (Decl) = N_Subprogram_Body then
375 Body_Acts_As_Spec := True;
377 elsif Nkind (Decl) = N_Subprogram_Declaration
378 or else Nkind (Decl) = N_Subprogram_Body_Stub
381 Body_Acts_As_Spec := False;
383 -- If we have none of an instantiation, subprogram body or
384 -- subprogram declaration, then it is not a case that we want
385 -- to check. (One case is a call to a generic formal subprogram,
386 -- where we do not want the check in the template).
394 if Elaboration_Checks_Suppressed (E_Scope)
395 or else Suppress_Elaboration_Warnings (E_Scope)
400 -- Exit when we get to compilation unit, not counting subunits
402 exit when Is_Compilation_Unit (E_Scope)
403 and then (Is_Child_Unit (E_Scope)
404 or else Scope (E_Scope) = Standard_Standard);
406 -- If we did not find a compilation unit, other than standard,
407 -- then nothing to check (happens in some instantiation cases)
409 if E_Scope = Standard_Standard then
412 -- Otherwise move up a scope looking for compilation unit
415 E_Scope := Scope (E_Scope);
419 -- No checks needed for pure or preelaborated compilation units
422 or else Is_Preelaborated (E_Scope)
427 -- If the generic entity is within a deeper instance than we are, then
428 -- either the instantiation to which we refer itself caused an ABE, in
429 -- which case that will be handled separately. Otherwise, we know that
430 -- the body we need appears as needed at the point of the instantiation.
431 -- However, this assumption is only valid if we are in static mode.
433 if not Dynamic_Elaboration_Checks
434 and then Instantiation_Depth (Sloc (Ent)) >
435 Instantiation_Depth (Sloc (N))
440 -- Do not give a warning for a package with no body
442 if Ekind (Ent) = E_Generic_Package
443 and then not Has_Generic_Body (N)
448 -- Case of entity is not in current unit (i.e. with'ed unit case)
450 if E_Scope /= C_Scope then
452 -- We are only interested in such calls if the outer call was from
453 -- elaboration code, or if we are in Dynamic_Elaboration_Checks mode.
455 if not From_Elab_Code and then not Dynamic_Elaboration_Checks then
459 -- Nothing to do if some scope said that no checks were required
465 -- Nothing to do for a generic instance, because in this case
466 -- the checking was at the point of instantiation of the generic
467 -- However, this shortcut is only applicable in static mode.
469 if Is_Generic_Instance (Ent) and not Dynamic_Elaboration_Checks then
473 -- Nothing to do if subprogram with no separate spec. However,
474 -- a call to Deep_Initialize may result in a call to a user-defined
475 -- Initialize procedure, which imposes a body dependency. This
476 -- happens only if the type is controlled and the Initialize
477 -- procedure is not inherited.
479 if Body_Acts_As_Spec then
480 if Is_TSS (Ent, TSS_Deep_Initialize) then
485 Typ := Etype (Next_Formal (First_Formal (Ent)));
487 if not Is_Controlled (Typ) then
490 Init := Find_Prim_Op (Typ, Name_Initialize);
492 if Comes_From_Source (Init) then
505 -- Check cases of internal units
507 Callee_Unit_Internal :=
508 Is_Internal_File_Name
509 (Unit_File_Name (Get_Source_Unit (E_Scope)));
511 -- Do not give a warning if the with'ed unit is internal
512 -- and this is the generic instantiation case (this saves a
513 -- lot of hassle dealing with the Text_IO special child units)
515 if Callee_Unit_Internal and Inst_Case then
519 if C_Scope = Standard_Standard then
520 Caller_Unit_Internal := False;
522 Caller_Unit_Internal :=
523 Is_Internal_File_Name
524 (Unit_File_Name (Get_Source_Unit (C_Scope)));
527 -- Do not give a warning if the with'ed unit is internal
528 -- and the caller is not internal (since the binder always
529 -- elaborates internal units first).
531 if Callee_Unit_Internal and (not Caller_Unit_Internal) then
535 -- For now, if debug flag -gnatdE is not set, do no checking for
536 -- one internal unit withing another. This fixes the problem with
537 -- the sgi build and storage errors. To be resolved later ???
539 if (Callee_Unit_Internal and Caller_Unit_Internal)
540 and then not Debug_Flag_EE
545 if Is_TSS (E, TSS_Deep_Initialize) then
549 -- If the call is in an instance, and the called entity is not
550 -- defined in the same instance, then the elaboration issue
551 -- focuses around the unit containing the template, it is
552 -- this unit which requires an Elaborate_All.
554 -- However, if we are doing dynamic elaboration, we need to
555 -- chase the call in the usual manner.
557 -- We do not handle the case of calling a generic formal correctly
558 -- in the static case. See test 4703-004 to explore this gap ???
560 Inst_Caller := Instantiation (Get_Source_File_Index (Sloc (N)));
561 Inst_Callee := Instantiation (Get_Source_File_Index (Sloc (Ent)));
563 if Inst_Caller = No_Location then
564 Unit_Caller := No_Unit;
566 Unit_Caller := Get_Source_Unit (N);
569 if Inst_Callee = No_Location then
570 Unit_Callee := No_Unit;
572 Unit_Callee := Get_Source_Unit (Ent);
575 if Unit_Caller /= No_Unit
576 and then Unit_Callee /= Unit_Caller
577 and then not Dynamic_Elaboration_Checks
579 E_Scope := Spec_Entity (Cunit_Entity (Unit_Caller));
581 -- If we don't get a spec entity, just ignore call. Not
582 -- quite clear why this check is necessary.
588 -- Otherwise step to enclosing compilation unit
590 while not Is_Compilation_Unit (E_Scope) loop
591 E_Scope := Scope (E_Scope);
594 -- For the case N is not an instance, or a call within instance
595 -- We recompute E_Scope for the error message, since we
596 -- do NOT want to go to the unit which has the ultimate
597 -- declaration in the case of renaming and derivation and
598 -- we also want to go to the generic unit in the case of
599 -- an instance, and no further.
602 -- Loop to carefully follow renamings and derivations
603 -- one step outside the current unit, but not further.
606 and then Present (Alias (Ent))
608 E_Scope := Alias (Ent);
614 while not Is_Compilation_Unit (E_Scope) loop
615 E_Scope := Scope (E_Scope);
618 -- If E_Scope is the same as C_Scope, it means that there
619 -- definitely was a local renaming or derivation, and we
620 -- are not yet out of the current unit.
622 exit when E_Scope /= C_Scope;
626 -- If no alias, there is a previous error
634 if Within_Elaborate_All (E_Scope) then
638 -- Find top level scope for called entity (not following renamings
639 -- or derivations). This is where the Elaborate_All will go if it
640 -- is needed. We start with the called entity, except in the case
641 -- of initialization procedures, where the init proc is in the root
642 -- package, where we start fromn the entity of the name in the call.
644 if Is_Entity_Name (Name (N))
645 and then Is_Init_Proc (Entity (Name (N)))
647 W_Scope := Scope (Entity (Name (N)));
652 while not Is_Compilation_Unit (W_Scope) loop
653 W_Scope := Scope (W_Scope);
656 -- Now check if an elaborate_all (or dynamic check) is needed
658 if not Suppress_Elaboration_Warnings (Ent)
659 and then not Elaboration_Checks_Suppressed (Ent)
660 and then not Suppress_Elaboration_Warnings (E_Scope)
661 and then not Elaboration_Checks_Suppressed (E_Scope)
662 and then Elab_Warnings
663 and then Generate_Warnings
667 ("instantiation of& may raise Program_Error?", N, Ent);
670 if Is_Init_Proc (Entity (Name (N)))
671 and then Comes_From_Source (Ent)
674 ("implicit call to & may raise Program_Error?", N, Ent);
678 ("call to & may raise Program_Error?", N, Ent);
682 Error_Msg_Qual_Level := Nat'Last;
684 ("\missing pragma Elaborate_All for&?", N, W_Scope);
685 Error_Msg_Qual_Level := 0;
688 -- Set flag to prevent further warnings for same unit
689 -- unless in All_Errors_Mode.
691 if not All_Errors_Mode and not Dynamic_Elaboration_Checks then
692 Set_Suppress_Elaboration_Warnings (W_Scope, True);
696 -- Check for runtime elaboration check required
698 if Dynamic_Elaboration_Checks then
699 if not Elaboration_Checks_Suppressed (Ent)
700 and then not Elaboration_Checks_Suppressed (W_Scope)
701 and then not Elaboration_Checks_Suppressed (E_Scope)
702 and then not Cunit_SC
704 -- Runtime elaboration check required. Generate check of the
705 -- elaboration Boolean for the unit containing the entity.
707 -- Note that for this case, we do check the real unit (the
708 -- one from following renamings, since that is the issue!)
710 -- Could this possibly miss a useless but required PE???
712 Insert_Elab_Check (N,
713 Make_Attribute_Reference (Loc,
714 Attribute_Name => Name_Elaborated,
717 (Spec_Entity (E_Scope), Loc)));
720 -- Case of static elaboration model
723 -- Do not do anything if elaboration checks suppressed. Note
724 -- that we check Ent here, not E, since we want the real entity
725 -- for the body to see if checks are suppressed for it, not the
726 -- dummy entry for renamings or derivations.
728 if Elaboration_Checks_Suppressed (Ent)
729 or else Elaboration_Checks_Suppressed (E_Scope)
730 or else Elaboration_Checks_Suppressed (W_Scope)
734 -- Here we need to generate an implicit elaborate all
737 -- Generate elaborate_all warning unless suppressed
739 if (Elab_Warnings and Generate_Warnings and not Inst_Case)
740 and then not Suppress_Elaboration_Warnings (Ent)
741 and then not Suppress_Elaboration_Warnings (E_Scope)
742 and then not Suppress_Elaboration_Warnings (W_Scope)
744 Error_Msg_Node_2 := W_Scope;
746 ("call to& in elaboration code " &
747 "requires pragma Elaborate_All on&?", N, E);
750 -- Set indication for binder to generate Elaborate_All
752 Set_Elaborate_All_Desirable (W_Scope);
753 Set_Suppress_Elaboration_Warnings (W_Scope, True);
757 -- Case of entity is in same unit as call or instantiation
759 elsif not Inter_Unit_Only then
760 Check_Internal_Call (N, Ent, Outer_Scope, E);
764 -----------------------------
765 -- Check_Bad_Instantiation --
766 -----------------------------
768 procedure Check_Bad_Instantiation (N : Node_Id) is
772 -- Nothing to do if we do not have an instantiation (happens in some
773 -- error cases, and also in the formal package declaration case)
775 if Nkind (N) not in N_Generic_Instantiation then
778 -- Nothing to do if serious errors detected (avoid cascaded errors)
780 elsif Serious_Errors_Detected /= 0 then
783 -- Nothing to do if not in full analysis mode
785 elsif not Full_Analysis then
788 -- Nothing to do if inside a generic template
790 elsif Inside_A_Generic then
793 -- Nothing to do if a library level instantiation
795 elsif Nkind (Parent (N)) = N_Compilation_Unit then
798 -- Nothing to do if we are compiling a proper body for semantic
799 -- purposes only. The generic body may be in another proper body.
802 Nkind (Parent (Unit_Declaration_Node (Main_Unit_Entity))) = N_Subunit
807 Ent := Get_Generic_Entity (N);
809 -- The case we are interested in is when the generic spec is in the
810 -- current declarative part
812 if not Same_Elaboration_Scope (Current_Scope, Scope (Ent))
813 or else not In_Same_Extended_Unit (Sloc (N), Sloc (Ent))
818 -- If the generic entity is within a deeper instance than we are, then
819 -- either the instantiation to which we refer itself caused an ABE, in
820 -- which case that will be handled separately. Otherwise, we know that
821 -- the body we need appears as needed at the point of the instantiation.
822 -- If they are both at the same level but not within the same instance
823 -- then the body of the generic will be in the earlier instance.
826 D1 : constant Int := Instantiation_Depth (Sloc (Ent));
827 D2 : constant Int := Instantiation_Depth (Sloc (N));
834 and then Is_Generic_Instance (Scope (Ent))
835 and then not In_Open_Scopes (Scope (Ent))
841 -- Now we can proceed, if the entity being called has a completion,
842 -- then we are definitely OK, since we have already seen the body.
844 if Has_Completion (Ent) then
848 -- If there is no body, then nothing to do
850 if not Has_Generic_Body (N) then
854 -- Here we definitely have a bad instantiation
857 ("?cannot instantiate& before body seen", N, Ent);
859 if Present (Instance_Spec (N)) then
860 Supply_Bodies (Instance_Spec (N));
864 ("\?Program_Error will be raised at run time", N);
865 Insert_Elab_Check (N);
866 Set_ABE_Is_Certain (N);
868 end Check_Bad_Instantiation;
870 ---------------------
871 -- Check_Elab_Call --
872 ---------------------
874 procedure Check_Elab_Call
876 Outer_Scope : Entity_Id := Empty)
881 function Get_Called_Ent return Entity_Id;
882 -- Retrieve called entity. If this is a call to a protected subprogram,
883 -- entity is a selected component. The callable entity may be absent,
884 -- in which case there is no check to perform. This happens with
885 -- non-analyzed calls in nested generics.
891 function Get_Called_Ent return Entity_Id is
900 elsif Nkind (Nam) = N_Selected_Component then
901 return Entity (Selector_Name (Nam));
903 elsif not Is_Entity_Name (Nam) then
911 -- Start of processing for Check_Elab_Call
914 -- For an entry call, check relevant restriction
916 if Nkind (N) = N_Entry_Call_Statement
917 and then not In_Subprogram_Or_Concurrent_Unit
919 Check_Restriction (No_Entry_Calls_In_Elaboration_Code, N);
921 -- Nothing to do if this is not a call (happens in some error
922 -- conditions, and in some cases where rewriting occurs).
924 elsif Nkind (N) /= N_Function_Call
925 and then Nkind (N) /= N_Procedure_Call_Statement
929 -- Nothing to do if this is a call already rewritten for elab checking.
931 elsif Nkind (Parent (N)) = N_Conditional_Expression then
934 -- Nothing to do if inside a generic template
936 elsif Inside_A_Generic
937 and then not Present (Enclosing_Generic_Body (N))
942 -- Here we have a call at elaboration time which must be checked
944 if Debug_Flag_LL then
945 Write_Str (" Check_Elab_Call: ");
948 or else not Is_Entity_Name (Name (N))
950 Write_Str ("<<not entity name>> ");
952 Write_Name (Chars (Entity (Name (N))));
955 Write_Str (" call at ");
956 Write_Location (Sloc (N));
960 -- Climb up the tree to make sure we are not inside a
961 -- default expression of a parameter specification or
962 -- a record component, since in both these cases, we
963 -- will be doing the actual call later, not now, and it
964 -- is at the time of the actual call (statically speaking)
965 -- that we must do our static check, not at the time of
966 -- its initial analysis).
969 while Present (P) loop
970 if Nkind (P) = N_Parameter_Specification
972 Nkind (P) = N_Component_Declaration
980 -- Stuff that happens only at the outer level
982 if No (Outer_Scope) then
983 Elab_Visited.Set_Last (0);
985 -- Nothing to do if current scope is Standard (this is a bit
986 -- odd, but it happens in the case of generic instantiations).
988 C_Scope := Current_Scope;
990 if C_Scope = Standard_Standard then
994 -- First case, we are in elaboration code
996 From_Elab_Code := not In_Subprogram_Or_Concurrent_Unit;
997 if From_Elab_Code then
999 -- Complain if call that comes from source in preelaborated
1000 -- unit and we are not inside a subprogram (i.e. we are in
1003 if Comes_From_Source (N)
1004 and then In_Preelaborated_Unit
1005 and then not In_Inlined_Body
1008 ("non-static call not allowed in preelaborated unit", N);
1012 -- Second case, we are inside a subprogram or concurrent unit
1013 -- i.e, we are not in elaboration code.
1016 -- In this case, the issue is whether we are inside the
1017 -- declarative part of the unit in which we live, or inside
1018 -- its statements. In the latter case, there is no issue of
1019 -- ABE calls at this level (a call from outside to the unit
1020 -- in which we live might cause an ABE, but that will be
1021 -- detected when we analyze that outer level call, as it
1022 -- recurses into the called unit).
1024 -- Climb up the tree, doing this test, and also testing
1025 -- for being inside a default expression, which, as
1026 -- discussed above, is not checked at this stage.
1035 -- If we find a parentless subtree, it seems safe to
1036 -- assume that we are not in a declarative part and
1037 -- that no checking is required.
1043 if Is_List_Member (P) then
1044 L := List_Containing (P);
1051 exit when Nkind (P) = N_Subunit;
1053 -- Filter out case of default expressions, where
1054 -- we do not do the check at this stage.
1056 if Nkind (P) = N_Parameter_Specification
1058 Nkind (P) = N_Component_Declaration
1063 if Nkind (P) = N_Subprogram_Body
1065 Nkind (P) = N_Protected_Body
1067 Nkind (P) = N_Task_Body
1069 Nkind (P) = N_Block_Statement
1071 if L = Declarations (P) then
1074 -- We are not in elaboration code, but we are doing
1075 -- dynamic elaboration checks, in this case, we still
1076 -- need to do the call, since the subprogram we are in
1077 -- could be called from another unit, also in dynamic
1078 -- elaboration check mode, at elaboration time.
1080 elsif Dynamic_Elaboration_Checks then
1082 -- This is a rather new check, going into version
1083 -- 3.14a1 for the first time (V1.80 of this unit),
1084 -- so we provide a debug flag to enable it. That
1085 -- way we have an easy work around for regressions
1086 -- that are caused by this new check. This debug
1087 -- flag can be removed later.
1089 if Debug_Flag_DD then
1093 -- Do the check in this case
1097 elsif Nkind (P) = N_Task_Body then
1099 -- The check is deferred until Check_Task_Activation
1100 -- but we need to capture local suppress pragmas
1101 -- that may inhibit checks on this call.
1103 Ent := Get_Called_Ent;
1108 elsif Elaboration_Checks_Suppressed (Current_Scope)
1109 or else Elaboration_Checks_Suppressed (Ent)
1110 or else Elaboration_Checks_Suppressed (Scope (Ent))
1112 Set_No_Elaboration_Check (N);
1117 -- Static model, call is not in elaboration code, we
1118 -- never need to worry, because in the static model
1119 -- the top level caller always takes care of things.
1130 Ent := Get_Called_Ent;
1136 -- Nothing to do if this is a recursive call (i.e. a call to
1137 -- an entity that is already in the Elab_Call stack)
1139 for J in 1 .. Elab_Visited.Last loop
1140 if Ent = Elab_Visited.Table (J) then
1145 -- See if we need to analyze this call. We analyze it if either of
1146 -- the following conditions is met:
1148 -- It is an inner level call (since in this case it was triggered
1149 -- by an outer level call from elaboration code), but only if the
1150 -- call is within the scope of the original outer level call.
1152 -- It is an outer level call from elaboration code, or the called
1153 -- entity is in the same elaboration scope.
1155 -- And in these cases, we will check both inter-unit calls and
1156 -- intra-unit (within a single unit) calls.
1158 C_Scope := Current_Scope;
1160 -- If not outer level call, then we follow it if it is within
1161 -- the original scope of the outer call.
1163 if Present (Outer_Scope)
1164 and then Within (Scope (Ent), Outer_Scope)
1167 Check_A_Call (N, Ent, Outer_Scope, Inter_Unit_Only => False);
1169 elsif Elaboration_Checks_Suppressed (Current_Scope) then
1172 elsif From_Elab_Code then
1174 Check_A_Call (N, Ent, Standard_Standard, Inter_Unit_Only => False);
1176 elsif Same_Elaboration_Scope (C_Scope, Scope (Ent)) then
1178 Check_A_Call (N, Ent, Scope (Ent), Inter_Unit_Only => False);
1180 -- If none of those cases holds, but Dynamic_Elaboration_Checks mode
1181 -- is set, then we will do the check, but only in the inter-unit case
1182 -- (this is to accommodate unguarded elaboration calls from other units
1183 -- in which this same mode is set). We don't want warnings in this case,
1184 -- it would generate warnings having nothing to do with elaboration.
1186 elsif Dynamic_Elaboration_Checks then
1192 Inter_Unit_Only => True,
1193 Generate_Warnings => False);
1195 -- Otherwise nothing to do
1201 -- A call to an Init_Proc in elaboration code may bring additional
1202 -- dependencies, if some of the record components thereof have
1203 -- initializations that are function calls that come from source.
1204 -- We treat the current node as a call to each of these functions,
1205 -- to check their elaboration impact.
1207 if Is_Init_Proc (Ent)
1208 and then From_Elab_Code
1210 Process_Init_Proc : declare
1211 Unit_Decl : constant Node_Id := Unit_Declaration_Node (Ent);
1213 function Process (Nod : Node_Id) return Traverse_Result;
1214 -- Find subprogram calls within body of init_proc for
1215 -- Traverse instantiation below.
1217 function Process (Nod : Node_Id) return Traverse_Result is
1221 if (Nkind (Nod) = N_Function_Call
1222 or else Nkind (Nod) = N_Procedure_Call_Statement)
1223 and then Is_Entity_Name (Name (Nod))
1225 Func := Entity (Name (Nod));
1227 if Comes_From_Source (Func) then
1229 (N, Func, Standard_Standard, Inter_Unit_Only => True);
1239 procedure Traverse_Body is new Traverse_Proc (Process);
1241 -- Start of processing for Process_Init_Proc
1244 if Nkind (Unit_Decl) = N_Subprogram_Body then
1245 Traverse_Body (Handled_Statement_Sequence (Unit_Decl));
1247 end Process_Init_Proc;
1249 end Check_Elab_Call;
1251 ----------------------
1252 -- Check_Elab_Calls --
1253 ----------------------
1255 procedure Check_Elab_Calls is
1257 -- If expansion is disabled, do not generate any checks. Also
1258 -- skip checks if any subunits are missing because in either
1259 -- case we lack the full information that we need, and no object
1260 -- file will be created in any case.
1262 if not Expander_Active
1263 or else Is_Generic_Unit (Cunit_Entity (Main_Unit))
1264 or else Subunits_Missing
1269 -- Skip delayed calls if we had any errors
1271 if Serious_Errors_Detected = 0 then
1272 Delaying_Elab_Checks := False;
1273 Expander_Mode_Save_And_Set (True);
1275 for J in Delay_Check.First .. Delay_Check.Last loop
1276 New_Scope (Delay_Check.Table (J).Curscop);
1277 From_Elab_Code := Delay_Check.Table (J).From_Elab_Code;
1279 Check_Internal_Call_Continue (
1280 N => Delay_Check.Table (J).N,
1281 E => Delay_Check.Table (J).E,
1282 Outer_Scope => Delay_Check.Table (J).Outer_Scope,
1283 Orig_Ent => Delay_Check.Table (J).Orig_Ent);
1288 -- Set Delaying_Elab_Checks back on for next main compilation
1290 Expander_Mode_Restore;
1291 Delaying_Elab_Checks := True;
1293 end Check_Elab_Calls;
1295 ------------------------------
1296 -- Check_Elab_Instantiation --
1297 ------------------------------
1299 procedure Check_Elab_Instantiation
1301 Outer_Scope : Entity_Id := Empty)
1306 -- Check for and deal with bad instantiation case. There is some
1307 -- duplicated code here, but we will worry about this later ???
1309 Check_Bad_Instantiation (N);
1311 if ABE_Is_Certain (N) then
1315 -- Nothing to do if we do not have an instantiation (happens in some
1316 -- error cases, and also in the formal package declaration case)
1318 if Nkind (N) not in N_Generic_Instantiation then
1322 -- Nothing to do if inside a generic template
1324 if Inside_A_Generic then
1328 Ent := Get_Generic_Entity (N);
1329 From_Elab_Code := not In_Subprogram_Or_Concurrent_Unit;
1331 -- See if we need to analyze this instantiation. We analyze it if
1332 -- either of the following conditions is met:
1334 -- It is an inner level instantiation (since in this case it was
1335 -- triggered by an outer level call from elaboration code), but
1336 -- only if the instantiation is within the scope of the original
1337 -- outer level call.
1339 -- It is an outer level instantiation from elaboration code, or the
1340 -- instantiated entity is in the same elaboratoin scope.
1342 -- And in these cases, we will check both the inter-unit case and
1343 -- the intra-unit (within a single unit) case.
1345 C_Scope := Current_Scope;
1347 if Present (Outer_Scope)
1348 and then Within (Scope (Ent), Outer_Scope)
1351 Check_A_Call (N, Ent, Outer_Scope, Inter_Unit_Only => False);
1353 elsif From_Elab_Code then
1355 Check_A_Call (N, Ent, Standard_Standard, Inter_Unit_Only => False);
1357 elsif Same_Elaboration_Scope (C_Scope, Scope (Ent)) then
1359 Check_A_Call (N, Ent, Scope (Ent), Inter_Unit_Only => False);
1361 -- If none of those cases holds, but Dynamic_Elaboration_Checks mode
1362 -- is set, then we will do the check, but only in the inter-unit case
1363 -- (this is to accommodate unguarded elaboration calls from other units
1364 -- in which this same mode is set). We inhibit warnings in this case,
1365 -- since this instantiation is not occurring in elaboration code.
1367 elsif Dynamic_Elaboration_Checks then
1373 Inter_Unit_Only => True,
1374 Generate_Warnings => False);
1379 end Check_Elab_Instantiation;
1381 -------------------------
1382 -- Check_Internal_Call --
1383 -------------------------
1385 procedure Check_Internal_Call
1388 Outer_Scope : Entity_Id;
1389 Orig_Ent : Entity_Id)
1391 Inst_Case : constant Boolean := Nkind (N) in N_Generic_Instantiation;
1394 -- If not function or procedure call or instantiation, then ignore
1395 -- call (this happens in some error case and rewriting cases)
1397 if Nkind (N) /= N_Function_Call
1399 Nkind (N) /= N_Procedure_Call_Statement
1405 -- Nothing to do if this is a call or instantiation that has
1406 -- already been found to be a sure ABE
1408 elsif ABE_Is_Certain (N) then
1411 -- Nothing to do if errors already detected (avoid cascaded errors)
1413 elsif Serious_Errors_Detected /= 0 then
1416 -- Nothing to do if not in full analysis mode
1418 elsif not Full_Analysis then
1421 -- Nothing to do if within a default expression, since the call
1422 -- is not actualy being made at this time.
1424 elsif In_Default_Expression then
1427 -- Nothing to do for call to intrinsic subprogram
1429 elsif Is_Intrinsic_Subprogram (E) then
1432 -- No need to trace local calls if checking task activation, because
1433 -- other local bodies are elaborated already.
1435 elsif In_Task_Activation then
1439 -- Delay this call if we are still delaying calls
1441 if Delaying_Elab_Checks then
1442 Delay_Check.Increment_Last;
1443 Delay_Check.Table (Delay_Check.Last) :=
1446 Orig_Ent => Orig_Ent,
1447 Curscop => Current_Scope,
1448 Outer_Scope => Outer_Scope,
1449 From_Elab_Code => From_Elab_Code);
1452 -- Otherwise, call phase 2 continuation right now
1455 Check_Internal_Call_Continue (N, E, Outer_Scope, Orig_Ent);
1458 end Check_Internal_Call;
1460 ----------------------------------
1461 -- Check_Internal_Call_Continue --
1462 ----------------------------------
1464 procedure Check_Internal_Call_Continue
1467 Outer_Scope : Entity_Id;
1468 Orig_Ent : Entity_Id)
1470 Loc : constant Source_Ptr := Sloc (N);
1471 Inst_Case : constant Boolean := Is_Generic_Unit (E);
1476 function Process (N : Node_Id) return Traverse_Result;
1477 -- Function applied to each node as we traverse the body.
1478 -- Checks for call that needs checking, and if so checks
1479 -- it. Always returns OK, so entire tree is traversed.
1485 function Process (N : Node_Id) return Traverse_Result is
1487 -- If user has specified that there are no entry calls in elaboration
1488 -- code, do not trace past an accept statement, because the rendez-
1489 -- vous will happen after elaboration.
1491 if (Nkind (Original_Node (N)) = N_Accept_Statement
1492 or else Nkind (Original_Node (N)) = N_Selective_Accept)
1493 and then Restriction_Active (No_Entry_Calls_In_Elaboration_Code)
1497 -- If we have a subprogram call, check it
1499 elsif Nkind (N) = N_Function_Call
1500 or else Nkind (N) = N_Procedure_Call_Statement
1502 Check_Elab_Call (N, Outer_Scope);
1505 -- If we have a generic instantiation, check it
1507 elsif Nkind (N) in N_Generic_Instantiation then
1508 Check_Elab_Instantiation (N, Outer_Scope);
1511 -- Skip subprogram bodies that come from source (wait for
1512 -- call to analyze these). The reason for the come from
1513 -- source test is to avoid catching task bodies.
1515 -- For task bodies, we should really avoid these too, waiting
1516 -- for the task activation, but that's too much trouble to
1517 -- catch for now, so we go in unconditionally. This is not
1518 -- so terrible, it means the error backtrace is not quite
1519 -- complete, and we are too eager to scan bodies of tasks
1520 -- that are unused, but this is hardly very significant!
1522 elsif Nkind (N) = N_Subprogram_Body
1523 and then Comes_From_Source (N)
1532 procedure Traverse is new Atree.Traverse_Proc;
1533 -- Traverse procedure using above Process function
1535 -- Start of processing for Check_Internal_Call_Continue
1538 -- Save outer level call if at outer level
1540 if Elab_Call.Last = 0 then
1541 Outer_Level_Sloc := Loc;
1544 Elab_Visited.Increment_Last;
1545 Elab_Visited.Table (Elab_Visited.Last) := E;
1547 -- If the call is to a function that renames a literal, no check
1550 if Ekind (E) = E_Enumeration_Literal then
1554 Sbody := Unit_Declaration_Node (E);
1556 if Nkind (Sbody) /= N_Subprogram_Body
1558 Nkind (Sbody) /= N_Package_Body
1560 Ebody := Corresponding_Body (Sbody);
1565 Sbody := Unit_Declaration_Node (Ebody);
1569 -- If the body appears after the outer level call or
1570 -- instantiation then we have an error case handled below.
1572 if Earlier_In_Extended_Unit (Outer_Level_Sloc, Sloc (Sbody))
1573 and then not In_Task_Activation
1577 -- If we have the instantiation case we are done, since we now
1578 -- know that the body of the generic appeared earlier.
1580 elsif Inst_Case then
1583 -- Otherwise we have a call, so we trace through the called
1584 -- body to see if it has any problems ..
1587 pragma Assert (Nkind (Sbody) = N_Subprogram_Body);
1589 Elab_Call.Increment_Last;
1590 Elab_Call.Table (Elab_Call.Last).Cloc := Loc;
1591 Elab_Call.Table (Elab_Call.Last).Ent := E;
1593 if Debug_Flag_LL then
1594 Write_Str ("Elab_Call.Last = ");
1595 Write_Int (Int (Elab_Call.Last));
1596 Write_Str (" Ent = ");
1597 Write_Name (Chars (E));
1599 Write_Location (Sloc (N));
1603 -- Now traverse declarations and statements of subprogram body.
1604 -- Note that we cannot simply Traverse (Sbody), since traverse
1605 -- does not normally visit subprogram bodies.
1608 Decl : Node_Id := First (Declarations (Sbody));
1611 while Present (Decl) loop
1617 Traverse (Handled_Statement_Sequence (Sbody));
1619 Elab_Call.Decrement_Last;
1623 -- Here is the case of calling a subprogram where the body has
1624 -- not yet been encountered, a warning message is needed.
1626 -- If we have nothing in the call stack, then this is at the
1627 -- outer level, and the ABE is bound to occur.
1629 if Elab_Call.Last = 0 then
1632 ("?cannot instantiate& before body seen", N, Orig_Ent);
1635 ("?cannot call& before body seen", N, Orig_Ent);
1639 ("\?Program_Error will be raised at run time", N);
1640 Insert_Elab_Check (N);
1642 -- Call is not at outer level
1645 -- Deal with dynamic elaboration check
1647 if not Elaboration_Checks_Suppressed (E) then
1648 Set_Elaboration_Entity_Required (E);
1650 -- Case of no elaboration entity allocated yet
1652 if No (Elaboration_Entity (E)) then
1654 -- Create object declaration for elaboration entity, and put it
1655 -- just in front of the spec of the subprogram or generic unit,
1656 -- in the same scope as this unit.
1659 Loce : constant Source_Ptr := Sloc (E);
1660 Ent : constant Entity_Id :=
1661 Make_Defining_Identifier (Loc,
1662 Chars => New_External_Name (Chars (E), 'E'));
1665 Set_Elaboration_Entity (E, Ent);
1666 New_Scope (Scope (E));
1668 Insert_Action (Declaration_Node (E),
1669 Make_Object_Declaration (Loce,
1670 Defining_Identifier => Ent,
1671 Object_Definition =>
1672 New_Occurrence_Of (Standard_Boolean, Loce),
1673 Expression => New_Occurrence_Of (Standard_False, Loce)));
1675 -- Set elaboration flag at the point of the body
1677 Set_Elaboration_Flag (Sbody, E);
1679 -- Kill current value indication. This is necessary
1680 -- because the tests of this flag are inserted out of
1681 -- sequence and must not pick up bogus indications of
1682 -- the wrong constant value. Also, this is never a true
1683 -- constant, since one way or another, it gets reset.
1685 Set_Current_Value (Ent, Empty);
1686 Set_Is_True_Constant (Ent, False);
1691 -- Generate check of the elaboration Boolean
1693 Insert_Elab_Check (N,
1694 New_Occurrence_Of (Elaboration_Entity (E), Loc));
1697 -- Generate the warning
1699 if not Suppress_Elaboration_Warnings (E)
1700 and then not Elaboration_Checks_Suppressed (E)
1704 ("instantiation of& may occur before body is seen?",
1708 ("call to& may occur before body is seen?", N, Orig_Ent);
1712 ("\Program_Error may be raised at run time?", N);
1718 -- Set flag to suppress further warnings on same subprogram
1719 -- unless in all errors mode
1721 if not All_Errors_Mode then
1722 Set_Suppress_Elaboration_Warnings (E);
1724 end Check_Internal_Call_Continue;
1726 ---------------------------
1727 -- Check_Task_Activation --
1728 ---------------------------
1730 procedure Check_Task_Activation (N : Node_Id) is
1731 Loc : constant Source_Ptr := Sloc (N);
1732 Inter_Procs : constant Elist_Id := New_Elmt_List;
1733 Intra_Procs : constant Elist_Id := New_Elmt_List;
1736 Task_Scope : Entity_Id;
1737 Cunit_SC : Boolean := False;
1740 Enclosing : Entity_Id;
1742 procedure Add_Task_Proc (Typ : Entity_Id);
1743 -- Add to Task_Procs the task body procedure(s) of task types in Typ.
1744 -- For record types, this procedure recurses over component types.
1746 procedure Collect_Tasks (Decls : List_Id);
1747 -- Collect the types of the tasks that are to be activated in the given
1748 -- list of declarations, in order to perform elaboration checks on the
1749 -- corresponding task procedures which are called implicitly here.
1751 function Outer_Unit (E : Entity_Id) return Entity_Id;
1752 -- find enclosing compilation unit of Entity, ignoring subunits, or
1753 -- else enclosing subprogram. If E is not a package, there is no need
1754 -- for inter-unit elaboration checks.
1760 procedure Add_Task_Proc (Typ : Entity_Id) is
1762 Proc : Entity_Id := Empty;
1765 if Is_Task_Type (Typ) then
1766 Proc := Get_Task_Body_Procedure (Typ);
1768 elsif Is_Array_Type (Typ)
1769 and then Has_Task (Base_Type (Typ))
1771 Add_Task_Proc (Component_Type (Typ));
1773 elsif Is_Record_Type (Typ)
1774 and then Has_Task (Base_Type (Typ))
1776 Comp := First_Component (Typ);
1778 while Present (Comp) loop
1779 Add_Task_Proc (Etype (Comp));
1780 Comp := Next_Component (Comp);
1784 -- If the task type is another unit, we will perform the usual
1785 -- elaboration check on its enclosing unit. If the type is in the
1786 -- same unit, we can trace the task body as for an internal call,
1787 -- but we only need to examine other external calls, because at
1788 -- the point the task is activated, internal subprogram bodies
1789 -- will have been elaborated already. We keep separate lists for
1790 -- each kind of task.
1792 -- Skip this test if errors have occurred, since in this case
1793 -- we can get false indications.
1795 if Serious_Errors_Detected /= 0 then
1799 if Present (Proc) then
1800 if Outer_Unit (Scope (Proc)) = Enclosing then
1802 if No (Corresponding_Body (Unit_Declaration_Node (Proc)))
1804 (not Is_Generic_Instance (Scope (Proc))
1806 Scope (Proc) = Scope (Defining_Identifier (Decl)))
1809 ("task will be activated before elaboration of its body?",
1812 ("Program_Error will be raised at run-time?", Decl);
1815 Present (Corresponding_Body (Unit_Declaration_Node (Proc)))
1817 Append_Elmt (Proc, Intra_Procs);
1821 Elmt := First_Elmt (Inter_Procs);
1823 -- No need for multiple entries of the same type.
1825 while Present (Elmt) loop
1826 if Node (Elmt) = Proc then
1833 Append_Elmt (Proc, Inter_Procs);
1842 procedure Collect_Tasks (Decls : List_Id) is
1844 if Present (Decls) then
1845 Decl := First (Decls);
1847 while Present (Decl) loop
1849 if Nkind (Decl) = N_Object_Declaration
1850 and then Has_Task (Etype (Defining_Identifier (Decl)))
1852 Add_Task_Proc (Etype (Defining_Identifier (Decl)));
1864 function Outer_Unit (E : Entity_Id) return Entity_Id is
1865 Outer : Entity_Id := E;
1868 while Present (Outer) loop
1869 if Elaboration_Checks_Suppressed (Outer) then
1873 exit when Is_Child_Unit (Outer)
1874 or else Scope (Outer) = Standard_Standard
1875 or else Ekind (Outer) /= E_Package;
1876 Outer := Scope (Outer);
1882 -- Start of processing for Check_Task_Activation
1885 Enclosing := Outer_Unit (Current_Scope);
1887 -- Find all tasks declared in the current unit.
1889 if Nkind (N) = N_Package_Body then
1890 P := Unit_Declaration_Node (Corresponding_Spec (N));
1892 Collect_Tasks (Declarations (N));
1893 Collect_Tasks (Visible_Declarations (Specification (P)));
1894 Collect_Tasks (Private_Declarations (Specification (P)));
1896 elsif Nkind (N) = N_Package_Declaration then
1897 Collect_Tasks (Visible_Declarations (Specification (N)));
1898 Collect_Tasks (Private_Declarations (Specification (N)));
1901 Collect_Tasks (Declarations (N));
1904 -- We only perform detailed checks in all tasks are library level
1905 -- entities. If the master is a subprogram or task, activation will
1906 -- depend on the activation of the master itself.
1907 -- Should dynamic checks be added in the more general case???
1909 if Ekind (Enclosing) /= E_Package then
1913 -- For task types defined in other units, we want the unit containing
1914 -- the task body to be elaborated before the current one.
1916 Elmt := First_Elmt (Inter_Procs);
1918 while Present (Elmt) loop
1920 Task_Scope := Outer_Unit (Scope (Ent));
1922 if not Is_Compilation_Unit (Task_Scope) then
1925 elsif Suppress_Elaboration_Warnings (Task_Scope)
1926 or else Elaboration_Checks_Suppressed (Task_Scope)
1930 elsif Dynamic_Elaboration_Checks then
1931 if not Elaboration_Checks_Suppressed (Ent)
1932 and then not Cunit_SC
1934 not Restriction_Active (No_Entry_Calls_In_Elaboration_Code)
1936 -- Runtime elaboration check required. generate check of the
1937 -- elaboration Boolean for the unit containing the entity.
1939 Insert_Elab_Check (N,
1940 Make_Attribute_Reference (Loc,
1941 Attribute_Name => Name_Elaborated,
1944 (Spec_Entity (Task_Scope), Loc)));
1948 -- Force the binder to elaborate other unit first
1950 if not Suppress_Elaboration_Warnings (Ent)
1951 and then not Elaboration_Checks_Suppressed (Ent)
1952 and then Elab_Warnings
1953 and then not Suppress_Elaboration_Warnings (Task_Scope)
1954 and then not Elaboration_Checks_Suppressed (Task_Scope)
1956 Error_Msg_Node_2 := Task_Scope;
1957 Error_Msg_NE ("activation of an instance of task type&" &
1958 " requires pragma Elaborate_All on &?", N, Ent);
1961 Set_Elaborate_All_Desirable (Task_Scope);
1962 Set_Suppress_Elaboration_Warnings (Task_Scope);
1968 -- For tasks declared in the current unit, trace other calls within
1969 -- the task procedure bodies, which are available.
1971 In_Task_Activation := True;
1972 Elmt := First_Elmt (Intra_Procs);
1974 while Present (Elmt) loop
1976 Check_Internal_Call_Continue (N, Ent, Enclosing, Ent);
1980 In_Task_Activation := False;
1981 end Check_Task_Activation;
1983 ----------------------
1984 -- Has_Generic_Body --
1985 ----------------------
1987 function Has_Generic_Body (N : Node_Id) return Boolean is
1988 Ent : constant Entity_Id := Get_Generic_Entity (N);
1989 Decl : constant Node_Id := Unit_Declaration_Node (Ent);
1992 function Find_Body_In (E : Entity_Id; N : Node_Id) return Node_Id;
1993 -- Determine if the list of nodes headed by N and linked by Next
1994 -- contains a package body for the package spec entity E, and if
1995 -- so return the package body. If not, then returns Empty.
1997 function Load_Package_Body (Nam : Unit_Name_Type) return Node_Id;
1998 -- This procedure is called load the unit whose name is given by Nam.
1999 -- This unit is being loaded to see whether it contains an optional
2000 -- generic body. The returned value is the loaded unit, which is
2001 -- always a package body (only package bodies can contain other
2002 -- entities in the sense in which Has_Generic_Body is interested).
2003 -- We only attempt to load bodies if we are generating code. If we
2004 -- are in semantics check only mode, then it would be wrong to load
2005 -- bodies that are not required from a semantic point of view, so
2006 -- in this case we return Empty. The result is that the caller may
2007 -- incorrectly decide that a generic spec does not have a body when
2008 -- in fact it does, but the only harm in this is that some warnings
2009 -- on elaboration problems may be lost in semantic checks only mode,
2010 -- which is not big loss. We also return Empty if we go for a body
2011 -- and it is not there.
2013 function Locate_Corresponding_Body (PE : Entity_Id) return Node_Id;
2014 -- PE is the entity for a package spec. This function locates the
2015 -- corresponding package body, returning Empty if none is found.
2016 -- The package body returned is fully parsed but may not yet be
2017 -- analyzed, so only syntactic fields should be referenced.
2023 function Find_Body_In (E : Entity_Id; N : Node_Id) return Node_Id is
2028 while Present (Nod) loop
2030 -- If we found the package body we are looking for, return it
2032 if Nkind (Nod) = N_Package_Body
2033 and then Chars (Defining_Unit_Name (Nod)) = Chars (E)
2037 -- If we found the stub for the body, go after the subunit,
2038 -- loading it if necessary.
2040 elsif Nkind (Nod) = N_Package_Body_Stub
2041 and then Chars (Defining_Identifier (Nod)) = Chars (E)
2043 if Present (Library_Unit (Nod)) then
2044 return Unit (Library_Unit (Nod));
2047 return Load_Package_Body (Get_Unit_Name (Nod));
2050 -- If neither package body nor stub, keep looking on chain
2060 -----------------------
2061 -- Load_Package_Body --
2062 -----------------------
2064 function Load_Package_Body (Nam : Unit_Name_Type) return Node_Id is
2065 U : Unit_Number_Type;
2068 if Operating_Mode /= Generate_Code then
2081 return Unit (Cunit (U));
2084 end Load_Package_Body;
2086 -------------------------------
2087 -- Locate_Corresponding_Body --
2088 -------------------------------
2090 function Locate_Corresponding_Body (PE : Entity_Id) return Node_Id is
2091 Spec : constant Node_Id := Declaration_Node (PE);
2092 Decl : constant Node_Id := Parent (Spec);
2093 Scop : constant Entity_Id := Scope (PE);
2097 if Is_Library_Level_Entity (PE) then
2099 -- If package is a library unit that requires a body, we have
2100 -- no choice but to go after that body because it might contain
2101 -- an optional body for the original generic package.
2103 if Unit_Requires_Body (PE) then
2105 -- Load the body. Note that we are a little careful here to
2106 -- use Spec to get the unit number, rather than PE or Decl,
2107 -- since in the case where the package is itself a library
2108 -- level instantiation, Spec will properly reference the
2109 -- generic template, which is what we really want.
2113 (Get_Body_Name (Unit_Name (Get_Source_Unit (Spec))));
2115 -- But if the package is a library unit that does NOT require
2116 -- a body, then no body is permitted, so we are sure that there
2117 -- is no body for the original generic package.
2123 -- Otherwise look and see if we are embedded in a further package
2125 elsif Is_Package (Scop) then
2127 -- If so, get the body of the enclosing package, and look in
2128 -- its package body for the package body we are looking for.
2130 PBody := Locate_Corresponding_Body (Scop);
2135 return Find_Body_In (PE, First (Declarations (PBody)));
2138 -- If we are not embedded in a further package, then the body
2139 -- must be in the same declarative part as we are.
2142 return Find_Body_In (PE, Next (Decl));
2144 end Locate_Corresponding_Body;
2146 -- Start of processing for Has_Generic_Body
2149 if Present (Corresponding_Body (Decl)) then
2152 elsif Unit_Requires_Body (Ent) then
2155 -- Compilation units cannot have optional bodies
2157 elsif Is_Compilation_Unit (Ent) then
2160 -- Otherwise look at what scope we are in
2163 Scop := Scope (Ent);
2165 -- Case of entity is in other than a package spec, in this case
2166 -- the body, if present, must be in the same declarative part.
2168 if not Is_Package (Scop) then
2173 P := Declaration_Node (Ent);
2175 -- Declaration node may get us a spec, so if so, go to
2176 -- the parent declaration.
2178 while not Is_List_Member (P) loop
2182 return Present (Find_Body_In (Ent, Next (P)));
2185 -- If the entity is in a package spec, then we have to locate
2186 -- the corresponding package body, and look there.
2190 PBody : constant Node_Id := Locate_Corresponding_Body (Scop);
2198 (Find_Body_In (Ent, (First (Declarations (PBody)))));
2203 end Has_Generic_Body;
2205 -----------------------
2206 -- Insert_Elab_Check --
2207 -----------------------
2209 procedure Insert_Elab_Check (N : Node_Id; C : Node_Id := Empty) is
2211 Loc : constant Source_Ptr := Sloc (N);
2214 -- If expansion is disabled, do not generate any checks. Also
2215 -- skip checks if any subunits are missing because in either
2216 -- case we lack the full information that we need, and no object
2217 -- file will be created in any case.
2219 if not Expander_Active or else Subunits_Missing then
2223 -- If we have a generic instantiation, where Instance_Spec is set,
2224 -- then this field points to a generic instance spec that has
2225 -- been inserted before the instantiation node itself, so that
2226 -- is where we want to insert a check.
2228 if Nkind (N) in N_Generic_Instantiation
2229 and then Present (Instance_Spec (N))
2231 Nod := Instance_Spec (N);
2236 -- If we are inserting at the top level, insert in Aux_Decls
2238 if Nkind (Parent (Nod)) = N_Compilation_Unit then
2240 ADN : constant Node_Id := Aux_Decls_Node (Parent (Nod));
2246 Make_Raise_Program_Error (Loc,
2247 Reason => PE_Access_Before_Elaboration);
2250 Make_Raise_Program_Error (Loc,
2251 Condition => Make_Op_Not (Loc, C),
2252 Reason => PE_Access_Before_Elaboration);
2255 if No (Declarations (ADN)) then
2256 Set_Declarations (ADN, New_List (R));
2258 Append_To (Declarations (ADN), R);
2264 -- Otherwise just insert before the node in question. However, if
2265 -- the context of the call has already been analyzed, an insertion
2266 -- will not work if it depends on subsequent expansion (e.g. a call in
2267 -- a branch of a short-circuit). In that case we replace the call with
2268 -- a conditional expression, or with a Raise if it is unconditional.
2269 -- Unfortunately this does not work if the call has a dynamic size,
2270 -- because gigi regards it as a dynamic-sized temporary. If such a call
2271 -- appears in a short-circuit expression, the elaboration check will be
2272 -- missed (rare enough ???). Otherwise, the code below inserts the check
2273 -- at the appropriate place before the call. Same applies in the even
2274 -- rarer case the return type has a known size but is unconstrained.
2277 if Nkind (N) = N_Function_Call
2278 and then Analyzed (Parent (N))
2279 and then Size_Known_At_Compile_Time (Etype (N))
2281 (not Has_Discriminants (Etype (N))
2282 or else Is_Constrained (Etype (N)))
2286 Typ : constant Entity_Id := Etype (N);
2287 Chk : constant Boolean := Do_Range_Check (N);
2289 R : constant Node_Id :=
2290 Make_Raise_Program_Error (Loc,
2291 Reason => PE_Access_Before_Elaboration);
2301 Make_Conditional_Expression (Loc,
2302 Expressions => New_List (C, Relocate_Node (N), R)));
2305 Analyze_And_Resolve (N, Typ);
2307 -- If the original call requires a range check, so does the
2308 -- conditional expression.
2311 Enable_Range_Check (N);
2313 Set_Do_Range_Check (N, False);
2320 Make_Raise_Program_Error (Loc,
2321 Reason => PE_Access_Before_Elaboration));
2324 Make_Raise_Program_Error (Loc,
2328 Reason => PE_Access_Before_Elaboration));
2332 end Insert_Elab_Check;
2338 procedure Output_Calls (N : Node_Id) is
2341 function Is_Printable_Error_Name (Nm : Name_Id) return Boolean;
2342 -- An internal function, used to determine if a name, Nm, is either
2343 -- a non-internal name, or is an internal name that is printable
2344 -- by the error message circuits (i.e. it has a single upper
2345 -- case letter at the end).
2347 function Is_Printable_Error_Name (Nm : Name_Id) return Boolean is
2349 if not Is_Internal_Name (Nm) then
2352 elsif Name_Len = 1 then
2356 Name_Len := Name_Len - 1;
2357 return not Is_Internal_Name;
2359 end Is_Printable_Error_Name;
2361 -- Start of processing for Output_Calls
2364 for J in reverse 1 .. Elab_Call.Last loop
2365 Error_Msg_Sloc := Elab_Call.Table (J).Cloc;
2367 Ent := Elab_Call.Table (J).Ent;
2369 if Is_Generic_Unit (Ent) then
2370 Error_Msg_NE ("\?& instantiated #", N, Ent);
2372 elsif Is_Init_Proc (Ent) then
2373 Error_Msg_N ("\?initialization procedure called #", N);
2375 elsif Is_Printable_Error_Name (Chars (Ent)) then
2376 Error_Msg_NE ("\?& called #", N, Ent);
2379 Error_Msg_N ("\? called #", N);
2384 ----------------------------
2385 -- Same_Elaboration_Scope --
2386 ----------------------------
2388 function Same_Elaboration_Scope (Scop1, Scop2 : Entity_Id) return Boolean is
2389 S1 : Entity_Id := Scop1;
2390 S2 : Entity_Id := Scop2;
2393 while S1 /= Standard_Standard
2394 and then (Ekind (S1) = E_Package
2396 Ekind (S1) = E_Block)
2401 while S2 /= Standard_Standard
2402 and then (Ekind (S2) = E_Package
2404 Ekind (S2) = E_Protected_Type
2406 Ekind (S2) = E_Block)
2412 end Same_Elaboration_Scope;
2418 procedure Set_C_Scope is
2420 while not Is_Compilation_Unit (C_Scope) loop
2421 C_Scope := Scope (C_Scope);
2429 function Spec_Entity (E : Entity_Id) return Entity_Id is
2433 -- Check for case of body entity
2434 -- Why is the check for E_Void needed???
2436 if Ekind (E) = E_Void
2437 or else Ekind (E) = E_Subprogram_Body
2438 or else Ekind (E) = E_Package_Body
2443 Decl := Parent (Decl);
2444 exit when Nkind (Decl) in N_Proper_Body;
2447 return Corresponding_Spec (Decl);
2458 procedure Supply_Bodies (N : Node_Id) is
2460 if Nkind (N) = N_Subprogram_Declaration then
2462 Ent : constant Entity_Id := Defining_Unit_Name (Specification (N));
2465 Set_Is_Imported (Ent);
2466 Set_Convention (Ent, Convention_Stubbed);
2469 elsif Nkind (N) = N_Package_Declaration then
2471 Spec : constant Node_Id := Specification (N);
2474 New_Scope (Defining_Unit_Name (Spec));
2475 Supply_Bodies (Visible_Declarations (Spec));
2476 Supply_Bodies (Private_Declarations (Spec));
2482 procedure Supply_Bodies (L : List_Id) is
2488 while Present (Elmt) loop
2489 Supply_Bodies (Elmt);
2499 function Within (E1, E2 : Entity_Id) return Boolean is
2509 elsif Scop = Standard_Standard then
2513 Scop := Scope (Scop);
2517 raise Program_Error;
2520 --------------------------
2521 -- Within_Elaborate_All --
2522 --------------------------
2524 function Within_Elaborate_All (E : Entity_Id) return Boolean is
2527 Elab_Id : Entity_Id;
2531 Item := First (Context_Items (Cunit (Current_Sem_Unit)));
2533 while Present (Item) loop
2534 if Nkind (Item) = N_Pragma
2535 and then Get_Pragma_Id (Chars (Item)) = Pragma_Elaborate_All
2537 if Error_Posted (Item) then
2539 -- Some previous error on the pragma itself
2546 Expression (First (Pragma_Argument_Associations (Item))));
2548 Par := Parent (Unit_Declaration_Node (Elab_Id));
2549 Item2 := First (Context_Items (Par));
2551 while Present (Item2) loop
2552 if Nkind (Item2) = N_With_Clause
2553 and then Entity (Name (Item2)) = E
2566 end Within_Elaborate_All;