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). However, we have to check calls
967 -- within component definitions (e.g., a function call
968 -- that determines an array component bound), so we
969 -- terminate the loop in that case.
972 while Present
(P
) loop
973 if Nkind
(P
) = N_Parameter_Specification
975 Nkind
(P
) = N_Component_Declaration
979 -- The call occurs within the constraint of a component,
980 -- so it must be checked.
982 elsif Nkind
(P
) = N_Component_Definition
then
990 -- Stuff that happens only at the outer level
992 if No
(Outer_Scope
) then
993 Elab_Visited
.Set_Last
(0);
995 -- Nothing to do if current scope is Standard (this is a bit
996 -- odd, but it happens in the case of generic instantiations).
998 C_Scope
:= Current_Scope
;
1000 if C_Scope
= Standard_Standard
then
1004 -- First case, we are in elaboration code
1006 From_Elab_Code
:= not In_Subprogram_Or_Concurrent_Unit
;
1007 if From_Elab_Code
then
1009 -- Complain if call that comes from source in preelaborated
1010 -- unit and we are not inside a subprogram (i.e. we are in
1013 if Comes_From_Source
(N
)
1014 and then In_Preelaborated_Unit
1015 and then not In_Inlined_Body
1018 ("non-static call not allowed in preelaborated unit", N
);
1022 -- Second case, we are inside a subprogram or concurrent unit
1023 -- i.e, we are not in elaboration code.
1026 -- In this case, the issue is whether we are inside the
1027 -- declarative part of the unit in which we live, or inside
1028 -- its statements. In the latter case, there is no issue of
1029 -- ABE calls at this level (a call from outside to the unit
1030 -- in which we live might cause an ABE, but that will be
1031 -- detected when we analyze that outer level call, as it
1032 -- recurses into the called unit).
1034 -- Climb up the tree, doing this test, and also testing
1035 -- for being inside a default expression, which, as
1036 -- discussed above, is not checked at this stage.
1045 -- If we find a parentless subtree, it seems safe to
1046 -- assume that we are not in a declarative part and
1047 -- that no checking is required.
1053 if Is_List_Member
(P
) then
1054 L
:= List_Containing
(P
);
1061 exit when Nkind
(P
) = N_Subunit
;
1063 -- Filter out case of default expressions, where
1064 -- we do not do the check at this stage.
1066 if Nkind
(P
) = N_Parameter_Specification
1068 Nkind
(P
) = N_Component_Declaration
1073 if Nkind
(P
) = N_Subprogram_Body
1075 Nkind
(P
) = N_Protected_Body
1077 Nkind
(P
) = N_Task_Body
1079 Nkind
(P
) = N_Block_Statement
1081 if L
= Declarations
(P
) then
1084 -- We are not in elaboration code, but we are doing
1085 -- dynamic elaboration checks, in this case, we still
1086 -- need to do the call, since the subprogram we are in
1087 -- could be called from another unit, also in dynamic
1088 -- elaboration check mode, at elaboration time.
1090 elsif Dynamic_Elaboration_Checks
then
1092 -- This is a rather new check, going into version
1093 -- 3.14a1 for the first time (V1.80 of this unit),
1094 -- so we provide a debug flag to enable it. That
1095 -- way we have an easy work around for regressions
1096 -- that are caused by this new check. This debug
1097 -- flag can be removed later.
1099 if Debug_Flag_DD
then
1103 -- Do the check in this case
1107 elsif Nkind
(P
) = N_Task_Body
then
1109 -- The check is deferred until Check_Task_Activation
1110 -- but we need to capture local suppress pragmas
1111 -- that may inhibit checks on this call.
1113 Ent
:= Get_Called_Ent
;
1118 elsif Elaboration_Checks_Suppressed
(Current_Scope
)
1119 or else Elaboration_Checks_Suppressed
(Ent
)
1120 or else Elaboration_Checks_Suppressed
(Scope
(Ent
))
1122 Set_No_Elaboration_Check
(N
);
1127 -- Static model, call is not in elaboration code, we
1128 -- never need to worry, because in the static model
1129 -- the top level caller always takes care of things.
1140 Ent
:= Get_Called_Ent
;
1146 -- Nothing to do if this is a recursive call (i.e. a call to
1147 -- an entity that is already in the Elab_Call stack)
1149 for J
in 1 .. Elab_Visited
.Last
loop
1150 if Ent
= Elab_Visited
.Table
(J
) then
1155 -- See if we need to analyze this call. We analyze it if either of
1156 -- the following conditions is met:
1158 -- It is an inner level call (since in this case it was triggered
1159 -- by an outer level call from elaboration code), but only if the
1160 -- call is within the scope of the original outer level call.
1162 -- It is an outer level call from elaboration code, or the called
1163 -- entity is in the same elaboration scope.
1165 -- And in these cases, we will check both inter-unit calls and
1166 -- intra-unit (within a single unit) calls.
1168 C_Scope
:= Current_Scope
;
1170 -- If not outer level call, then we follow it if it is within
1171 -- the original scope of the outer call.
1173 if Present
(Outer_Scope
)
1174 and then Within
(Scope
(Ent
), Outer_Scope
)
1177 Check_A_Call
(N
, Ent
, Outer_Scope
, Inter_Unit_Only
=> False);
1179 elsif Elaboration_Checks_Suppressed
(Current_Scope
) then
1182 elsif From_Elab_Code
then
1184 Check_A_Call
(N
, Ent
, Standard_Standard
, Inter_Unit_Only
=> False);
1186 elsif Same_Elaboration_Scope
(C_Scope
, Scope
(Ent
)) then
1188 Check_A_Call
(N
, Ent
, Scope
(Ent
), Inter_Unit_Only
=> False);
1190 -- If none of those cases holds, but Dynamic_Elaboration_Checks mode
1191 -- is set, then we will do the check, but only in the inter-unit case
1192 -- (this is to accommodate unguarded elaboration calls from other units
1193 -- in which this same mode is set). We don't want warnings in this case,
1194 -- it would generate warnings having nothing to do with elaboration.
1196 elsif Dynamic_Elaboration_Checks
then
1202 Inter_Unit_Only
=> True,
1203 Generate_Warnings
=> False);
1205 -- Otherwise nothing to do
1211 -- A call to an Init_Proc in elaboration code may bring additional
1212 -- dependencies, if some of the record components thereof have
1213 -- initializations that are function calls that come from source.
1214 -- We treat the current node as a call to each of these functions,
1215 -- to check their elaboration impact.
1217 if Is_Init_Proc
(Ent
)
1218 and then From_Elab_Code
1220 Process_Init_Proc
: declare
1221 Unit_Decl
: constant Node_Id
:= Unit_Declaration_Node
(Ent
);
1223 function Process
(Nod
: Node_Id
) return Traverse_Result
;
1224 -- Find subprogram calls within body of init_proc for
1225 -- Traverse instantiation below.
1227 function Process
(Nod
: Node_Id
) return Traverse_Result
is
1231 if (Nkind
(Nod
) = N_Function_Call
1232 or else Nkind
(Nod
) = N_Procedure_Call_Statement
)
1233 and then Is_Entity_Name
(Name
(Nod
))
1235 Func
:= Entity
(Name
(Nod
));
1237 if Comes_From_Source
(Func
) then
1239 (N
, Func
, Standard_Standard
, Inter_Unit_Only
=> True);
1249 procedure Traverse_Body
is new Traverse_Proc
(Process
);
1251 -- Start of processing for Process_Init_Proc
1254 if Nkind
(Unit_Decl
) = N_Subprogram_Body
then
1255 Traverse_Body
(Handled_Statement_Sequence
(Unit_Decl
));
1257 end Process_Init_Proc
;
1259 end Check_Elab_Call
;
1261 ----------------------
1262 -- Check_Elab_Calls --
1263 ----------------------
1265 procedure Check_Elab_Calls
is
1267 -- If expansion is disabled, do not generate any checks. Also
1268 -- skip checks if any subunits are missing because in either
1269 -- case we lack the full information that we need, and no object
1270 -- file will be created in any case.
1272 if not Expander_Active
1273 or else Is_Generic_Unit
(Cunit_Entity
(Main_Unit
))
1274 or else Subunits_Missing
1279 -- Skip delayed calls if we had any errors
1281 if Serious_Errors_Detected
= 0 then
1282 Delaying_Elab_Checks
:= False;
1283 Expander_Mode_Save_And_Set
(True);
1285 for J
in Delay_Check
.First
.. Delay_Check
.Last
loop
1286 New_Scope
(Delay_Check
.Table
(J
).Curscop
);
1287 From_Elab_Code
:= Delay_Check
.Table
(J
).From_Elab_Code
;
1289 Check_Internal_Call_Continue
(
1290 N
=> Delay_Check
.Table
(J
).N
,
1291 E
=> Delay_Check
.Table
(J
).E
,
1292 Outer_Scope
=> Delay_Check
.Table
(J
).Outer_Scope
,
1293 Orig_Ent
=> Delay_Check
.Table
(J
).Orig_Ent
);
1298 -- Set Delaying_Elab_Checks back on for next main compilation
1300 Expander_Mode_Restore
;
1301 Delaying_Elab_Checks
:= True;
1303 end Check_Elab_Calls
;
1305 ------------------------------
1306 -- Check_Elab_Instantiation --
1307 ------------------------------
1309 procedure Check_Elab_Instantiation
1311 Outer_Scope
: Entity_Id
:= Empty
)
1316 -- Check for and deal with bad instantiation case. There is some
1317 -- duplicated code here, but we will worry about this later ???
1319 Check_Bad_Instantiation
(N
);
1321 if ABE_Is_Certain
(N
) then
1325 -- Nothing to do if we do not have an instantiation (happens in some
1326 -- error cases, and also in the formal package declaration case)
1328 if Nkind
(N
) not in N_Generic_Instantiation
then
1332 -- Nothing to do if inside a generic template
1334 if Inside_A_Generic
then
1338 Ent
:= Get_Generic_Entity
(N
);
1339 From_Elab_Code
:= not In_Subprogram_Or_Concurrent_Unit
;
1341 -- See if we need to analyze this instantiation. We analyze it if
1342 -- either of the following conditions is met:
1344 -- It is an inner level instantiation (since in this case it was
1345 -- triggered by an outer level call from elaboration code), but
1346 -- only if the instantiation is within the scope of the original
1347 -- outer level call.
1349 -- It is an outer level instantiation from elaboration code, or the
1350 -- instantiated entity is in the same elaboratoin scope.
1352 -- And in these cases, we will check both the inter-unit case and
1353 -- the intra-unit (within a single unit) case.
1355 C_Scope
:= Current_Scope
;
1357 if Present
(Outer_Scope
)
1358 and then Within
(Scope
(Ent
), Outer_Scope
)
1361 Check_A_Call
(N
, Ent
, Outer_Scope
, Inter_Unit_Only
=> False);
1363 elsif From_Elab_Code
then
1365 Check_A_Call
(N
, Ent
, Standard_Standard
, Inter_Unit_Only
=> False);
1367 elsif Same_Elaboration_Scope
(C_Scope
, Scope
(Ent
)) then
1369 Check_A_Call
(N
, Ent
, Scope
(Ent
), Inter_Unit_Only
=> False);
1371 -- If none of those cases holds, but Dynamic_Elaboration_Checks mode
1372 -- is set, then we will do the check, but only in the inter-unit case
1373 -- (this is to accommodate unguarded elaboration calls from other units
1374 -- in which this same mode is set). We inhibit warnings in this case,
1375 -- since this instantiation is not occurring in elaboration code.
1377 elsif Dynamic_Elaboration_Checks
then
1383 Inter_Unit_Only
=> True,
1384 Generate_Warnings
=> False);
1389 end Check_Elab_Instantiation
;
1391 -------------------------
1392 -- Check_Internal_Call --
1393 -------------------------
1395 procedure Check_Internal_Call
1398 Outer_Scope
: Entity_Id
;
1399 Orig_Ent
: Entity_Id
)
1401 Inst_Case
: constant Boolean := Nkind
(N
) in N_Generic_Instantiation
;
1404 -- If not function or procedure call or instantiation, then ignore
1405 -- call (this happens in some error case and rewriting cases)
1407 if Nkind
(N
) /= N_Function_Call
1409 Nkind
(N
) /= N_Procedure_Call_Statement
1415 -- Nothing to do if this is a call or instantiation that has
1416 -- already been found to be a sure ABE
1418 elsif ABE_Is_Certain
(N
) then
1421 -- Nothing to do if errors already detected (avoid cascaded errors)
1423 elsif Serious_Errors_Detected
/= 0 then
1426 -- Nothing to do if not in full analysis mode
1428 elsif not Full_Analysis
then
1431 -- Nothing to do if within a default expression, since the call
1432 -- is not actualy being made at this time.
1434 elsif In_Default_Expression
then
1437 -- Nothing to do for call to intrinsic subprogram
1439 elsif Is_Intrinsic_Subprogram
(E
) then
1442 -- No need to trace local calls if checking task activation, because
1443 -- other local bodies are elaborated already.
1445 elsif In_Task_Activation
then
1449 -- Delay this call if we are still delaying calls
1451 if Delaying_Elab_Checks
then
1452 Delay_Check
.Increment_Last
;
1453 Delay_Check
.Table
(Delay_Check
.Last
) :=
1456 Orig_Ent
=> Orig_Ent
,
1457 Curscop
=> Current_Scope
,
1458 Outer_Scope
=> Outer_Scope
,
1459 From_Elab_Code
=> From_Elab_Code
);
1462 -- Otherwise, call phase 2 continuation right now
1465 Check_Internal_Call_Continue
(N
, E
, Outer_Scope
, Orig_Ent
);
1468 end Check_Internal_Call
;
1470 ----------------------------------
1471 -- Check_Internal_Call_Continue --
1472 ----------------------------------
1474 procedure Check_Internal_Call_Continue
1477 Outer_Scope
: Entity_Id
;
1478 Orig_Ent
: Entity_Id
)
1480 Loc
: constant Source_Ptr
:= Sloc
(N
);
1481 Inst_Case
: constant Boolean := Is_Generic_Unit
(E
);
1486 function Process
(N
: Node_Id
) return Traverse_Result
;
1487 -- Function applied to each node as we traverse the body.
1488 -- Checks for call that needs checking, and if so checks
1489 -- it. Always returns OK, so entire tree is traversed.
1495 function Process
(N
: Node_Id
) return Traverse_Result
is
1497 -- If user has specified that there are no entry calls in elaboration
1498 -- code, do not trace past an accept statement, because the rendez-
1499 -- vous will happen after elaboration.
1501 if (Nkind
(Original_Node
(N
)) = N_Accept_Statement
1502 or else Nkind
(Original_Node
(N
)) = N_Selective_Accept
)
1503 and then Restriction_Active
(No_Entry_Calls_In_Elaboration_Code
)
1507 -- If we have a subprogram call, check it
1509 elsif Nkind
(N
) = N_Function_Call
1510 or else Nkind
(N
) = N_Procedure_Call_Statement
1512 Check_Elab_Call
(N
, Outer_Scope
);
1515 -- If we have a generic instantiation, check it
1517 elsif Nkind
(N
) in N_Generic_Instantiation
then
1518 Check_Elab_Instantiation
(N
, Outer_Scope
);
1521 -- Skip subprogram bodies that come from source (wait for
1522 -- call to analyze these). The reason for the come from
1523 -- source test is to avoid catching task bodies.
1525 -- For task bodies, we should really avoid these too, waiting
1526 -- for the task activation, but that's too much trouble to
1527 -- catch for now, so we go in unconditionally. This is not
1528 -- so terrible, it means the error backtrace is not quite
1529 -- complete, and we are too eager to scan bodies of tasks
1530 -- that are unused, but this is hardly very significant!
1532 elsif Nkind
(N
) = N_Subprogram_Body
1533 and then Comes_From_Source
(N
)
1542 procedure Traverse
is new Atree
.Traverse_Proc
;
1543 -- Traverse procedure using above Process function
1545 -- Start of processing for Check_Internal_Call_Continue
1548 -- Save outer level call if at outer level
1550 if Elab_Call
.Last
= 0 then
1551 Outer_Level_Sloc
:= Loc
;
1554 Elab_Visited
.Increment_Last
;
1555 Elab_Visited
.Table
(Elab_Visited
.Last
) := E
;
1557 -- If the call is to a function that renames a literal, no check
1560 if Ekind
(E
) = E_Enumeration_Literal
then
1564 Sbody
:= Unit_Declaration_Node
(E
);
1566 if Nkind
(Sbody
) /= N_Subprogram_Body
1568 Nkind
(Sbody
) /= N_Package_Body
1570 Ebody
:= Corresponding_Body
(Sbody
);
1575 Sbody
:= Unit_Declaration_Node
(Ebody
);
1579 -- If the body appears after the outer level call or
1580 -- instantiation then we have an error case handled below.
1582 if Earlier_In_Extended_Unit
(Outer_Level_Sloc
, Sloc
(Sbody
))
1583 and then not In_Task_Activation
1587 -- If we have the instantiation case we are done, since we now
1588 -- know that the body of the generic appeared earlier.
1590 elsif Inst_Case
then
1593 -- Otherwise we have a call, so we trace through the called
1594 -- body to see if it has any problems ..
1597 pragma Assert
(Nkind
(Sbody
) = N_Subprogram_Body
);
1599 Elab_Call
.Increment_Last
;
1600 Elab_Call
.Table
(Elab_Call
.Last
).Cloc
:= Loc
;
1601 Elab_Call
.Table
(Elab_Call
.Last
).Ent
:= E
;
1603 if Debug_Flag_LL
then
1604 Write_Str
("Elab_Call.Last = ");
1605 Write_Int
(Int
(Elab_Call
.Last
));
1606 Write_Str
(" Ent = ");
1607 Write_Name
(Chars
(E
));
1609 Write_Location
(Sloc
(N
));
1613 -- Now traverse declarations and statements of subprogram body.
1614 -- Note that we cannot simply Traverse (Sbody), since traverse
1615 -- does not normally visit subprogram bodies.
1618 Decl
: Node_Id
:= First
(Declarations
(Sbody
));
1621 while Present
(Decl
) loop
1627 Traverse
(Handled_Statement_Sequence
(Sbody
));
1629 Elab_Call
.Decrement_Last
;
1633 -- Here is the case of calling a subprogram where the body has
1634 -- not yet been encountered, a warning message is needed.
1636 -- If we have nothing in the call stack, then this is at the
1637 -- outer level, and the ABE is bound to occur.
1639 if Elab_Call
.Last
= 0 then
1642 ("?cannot instantiate& before body seen", N
, Orig_Ent
);
1645 ("?cannot call& before body seen", N
, Orig_Ent
);
1649 ("\?Program_Error will be raised at run time", N
);
1650 Insert_Elab_Check
(N
);
1652 -- Call is not at outer level
1655 -- Deal with dynamic elaboration check
1657 if not Elaboration_Checks_Suppressed
(E
) then
1658 Set_Elaboration_Entity_Required
(E
);
1660 -- Case of no elaboration entity allocated yet
1662 if No
(Elaboration_Entity
(E
)) then
1664 -- Create object declaration for elaboration entity, and put it
1665 -- just in front of the spec of the subprogram or generic unit,
1666 -- in the same scope as this unit.
1669 Loce
: constant Source_Ptr
:= Sloc
(E
);
1670 Ent
: constant Entity_Id
:=
1671 Make_Defining_Identifier
(Loc
,
1672 Chars
=> New_External_Name
(Chars
(E
), 'E'));
1675 Set_Elaboration_Entity
(E
, Ent
);
1676 New_Scope
(Scope
(E
));
1678 Insert_Action
(Declaration_Node
(E
),
1679 Make_Object_Declaration
(Loce
,
1680 Defining_Identifier
=> Ent
,
1681 Object_Definition
=>
1682 New_Occurrence_Of
(Standard_Boolean
, Loce
),
1683 Expression
=> New_Occurrence_Of
(Standard_False
, Loce
)));
1685 -- Set elaboration flag at the point of the body
1687 Set_Elaboration_Flag
(Sbody
, E
);
1689 -- Kill current value indication. This is necessary
1690 -- because the tests of this flag are inserted out of
1691 -- sequence and must not pick up bogus indications of
1692 -- the wrong constant value. Also, this is never a true
1693 -- constant, since one way or another, it gets reset.
1695 Set_Current_Value
(Ent
, Empty
);
1696 Set_Is_True_Constant
(Ent
, False);
1701 -- Generate check of the elaboration Boolean
1703 Insert_Elab_Check
(N
,
1704 New_Occurrence_Of
(Elaboration_Entity
(E
), Loc
));
1707 -- Generate the warning
1709 if not Suppress_Elaboration_Warnings
(E
)
1710 and then not Elaboration_Checks_Suppressed
(E
)
1714 ("instantiation of& may occur before body is seen?",
1718 ("call to& may occur before body is seen?", N
, Orig_Ent
);
1722 ("\Program_Error may be raised at run time?", N
);
1728 -- Set flag to suppress further warnings on same subprogram
1729 -- unless in all errors mode
1731 if not All_Errors_Mode
then
1732 Set_Suppress_Elaboration_Warnings
(E
);
1734 end Check_Internal_Call_Continue
;
1736 ---------------------------
1737 -- Check_Task_Activation --
1738 ---------------------------
1740 procedure Check_Task_Activation
(N
: Node_Id
) is
1741 Loc
: constant Source_Ptr
:= Sloc
(N
);
1742 Inter_Procs
: constant Elist_Id
:= New_Elmt_List
;
1743 Intra_Procs
: constant Elist_Id
:= New_Elmt_List
;
1746 Task_Scope
: Entity_Id
;
1747 Cunit_SC
: Boolean := False;
1750 Enclosing
: Entity_Id
;
1752 procedure Add_Task_Proc
(Typ
: Entity_Id
);
1753 -- Add to Task_Procs the task body procedure(s) of task types in Typ.
1754 -- For record types, this procedure recurses over component types.
1756 procedure Collect_Tasks
(Decls
: List_Id
);
1757 -- Collect the types of the tasks that are to be activated in the given
1758 -- list of declarations, in order to perform elaboration checks on the
1759 -- corresponding task procedures which are called implicitly here.
1761 function Outer_Unit
(E
: Entity_Id
) return Entity_Id
;
1762 -- find enclosing compilation unit of Entity, ignoring subunits, or
1763 -- else enclosing subprogram. If E is not a package, there is no need
1764 -- for inter-unit elaboration checks.
1770 procedure Add_Task_Proc
(Typ
: Entity_Id
) is
1772 Proc
: Entity_Id
:= Empty
;
1775 if Is_Task_Type
(Typ
) then
1776 Proc
:= Get_Task_Body_Procedure
(Typ
);
1778 elsif Is_Array_Type
(Typ
)
1779 and then Has_Task
(Base_Type
(Typ
))
1781 Add_Task_Proc
(Component_Type
(Typ
));
1783 elsif Is_Record_Type
(Typ
)
1784 and then Has_Task
(Base_Type
(Typ
))
1786 Comp
:= First_Component
(Typ
);
1788 while Present
(Comp
) loop
1789 Add_Task_Proc
(Etype
(Comp
));
1790 Comp
:= Next_Component
(Comp
);
1794 -- If the task type is another unit, we will perform the usual
1795 -- elaboration check on its enclosing unit. If the type is in the
1796 -- same unit, we can trace the task body as for an internal call,
1797 -- but we only need to examine other external calls, because at
1798 -- the point the task is activated, internal subprogram bodies
1799 -- will have been elaborated already. We keep separate lists for
1800 -- each kind of task.
1802 -- Skip this test if errors have occurred, since in this case
1803 -- we can get false indications.
1805 if Serious_Errors_Detected
/= 0 then
1809 if Present
(Proc
) then
1810 if Outer_Unit
(Scope
(Proc
)) = Enclosing
then
1812 if No
(Corresponding_Body
(Unit_Declaration_Node
(Proc
)))
1814 (not Is_Generic_Instance
(Scope
(Proc
))
1816 Scope
(Proc
) = Scope
(Defining_Identifier
(Decl
)))
1819 ("task will be activated before elaboration of its body?",
1822 ("Program_Error will be raised at run-time?", Decl
);
1825 Present
(Corresponding_Body
(Unit_Declaration_Node
(Proc
)))
1827 Append_Elmt
(Proc
, Intra_Procs
);
1831 Elmt
:= First_Elmt
(Inter_Procs
);
1833 -- No need for multiple entries of the same type.
1835 while Present
(Elmt
) loop
1836 if Node
(Elmt
) = Proc
then
1843 Append_Elmt
(Proc
, Inter_Procs
);
1852 procedure Collect_Tasks
(Decls
: List_Id
) is
1854 if Present
(Decls
) then
1855 Decl
:= First
(Decls
);
1857 while Present
(Decl
) loop
1859 if Nkind
(Decl
) = N_Object_Declaration
1860 and then Has_Task
(Etype
(Defining_Identifier
(Decl
)))
1862 Add_Task_Proc
(Etype
(Defining_Identifier
(Decl
)));
1874 function Outer_Unit
(E
: Entity_Id
) return Entity_Id
is
1875 Outer
: Entity_Id
:= E
;
1878 while Present
(Outer
) loop
1879 if Elaboration_Checks_Suppressed
(Outer
) then
1883 exit when Is_Child_Unit
(Outer
)
1884 or else Scope
(Outer
) = Standard_Standard
1885 or else Ekind
(Outer
) /= E_Package
;
1886 Outer
:= Scope
(Outer
);
1892 -- Start of processing for Check_Task_Activation
1895 Enclosing
:= Outer_Unit
(Current_Scope
);
1897 -- Find all tasks declared in the current unit.
1899 if Nkind
(N
) = N_Package_Body
then
1900 P
:= Unit_Declaration_Node
(Corresponding_Spec
(N
));
1902 Collect_Tasks
(Declarations
(N
));
1903 Collect_Tasks
(Visible_Declarations
(Specification
(P
)));
1904 Collect_Tasks
(Private_Declarations
(Specification
(P
)));
1906 elsif Nkind
(N
) = N_Package_Declaration
then
1907 Collect_Tasks
(Visible_Declarations
(Specification
(N
)));
1908 Collect_Tasks
(Private_Declarations
(Specification
(N
)));
1911 Collect_Tasks
(Declarations
(N
));
1914 -- We only perform detailed checks in all tasks are library level
1915 -- entities. If the master is a subprogram or task, activation will
1916 -- depend on the activation of the master itself.
1917 -- Should dynamic checks be added in the more general case???
1919 if Ekind
(Enclosing
) /= E_Package
then
1923 -- For task types defined in other units, we want the unit containing
1924 -- the task body to be elaborated before the current one.
1926 Elmt
:= First_Elmt
(Inter_Procs
);
1928 while Present
(Elmt
) loop
1930 Task_Scope
:= Outer_Unit
(Scope
(Ent
));
1932 if not Is_Compilation_Unit
(Task_Scope
) then
1935 elsif Suppress_Elaboration_Warnings
(Task_Scope
)
1936 or else Elaboration_Checks_Suppressed
(Task_Scope
)
1940 elsif Dynamic_Elaboration_Checks
then
1941 if not Elaboration_Checks_Suppressed
(Ent
)
1942 and then not Cunit_SC
1944 not Restriction_Active
(No_Entry_Calls_In_Elaboration_Code
)
1946 -- Runtime elaboration check required. generate check of the
1947 -- elaboration Boolean for the unit containing the entity.
1949 Insert_Elab_Check
(N
,
1950 Make_Attribute_Reference
(Loc
,
1951 Attribute_Name
=> Name_Elaborated
,
1954 (Spec_Entity
(Task_Scope
), Loc
)));
1958 -- Force the binder to elaborate other unit first
1960 if not Suppress_Elaboration_Warnings
(Ent
)
1961 and then not Elaboration_Checks_Suppressed
(Ent
)
1962 and then Elab_Warnings
1963 and then not Suppress_Elaboration_Warnings
(Task_Scope
)
1964 and then not Elaboration_Checks_Suppressed
(Task_Scope
)
1966 Error_Msg_Node_2
:= Task_Scope
;
1967 Error_Msg_NE
("activation of an instance of task type&" &
1968 " requires pragma Elaborate_All on &?", N
, Ent
);
1971 Set_Elaborate_All_Desirable
(Task_Scope
);
1972 Set_Suppress_Elaboration_Warnings
(Task_Scope
);
1978 -- For tasks declared in the current unit, trace other calls within
1979 -- the task procedure bodies, which are available.
1981 In_Task_Activation
:= True;
1982 Elmt
:= First_Elmt
(Intra_Procs
);
1984 while Present
(Elmt
) loop
1986 Check_Internal_Call_Continue
(N
, Ent
, Enclosing
, Ent
);
1990 In_Task_Activation
:= False;
1991 end Check_Task_Activation
;
1993 ----------------------
1994 -- Has_Generic_Body --
1995 ----------------------
1997 function Has_Generic_Body
(N
: Node_Id
) return Boolean is
1998 Ent
: constant Entity_Id
:= Get_Generic_Entity
(N
);
1999 Decl
: constant Node_Id
:= Unit_Declaration_Node
(Ent
);
2002 function Find_Body_In
(E
: Entity_Id
; N
: Node_Id
) return Node_Id
;
2003 -- Determine if the list of nodes headed by N and linked by Next
2004 -- contains a package body for the package spec entity E, and if
2005 -- so return the package body. If not, then returns Empty.
2007 function Load_Package_Body
(Nam
: Unit_Name_Type
) return Node_Id
;
2008 -- This procedure is called load the unit whose name is given by Nam.
2009 -- This unit is being loaded to see whether it contains an optional
2010 -- generic body. The returned value is the loaded unit, which is
2011 -- always a package body (only package bodies can contain other
2012 -- entities in the sense in which Has_Generic_Body is interested).
2013 -- We only attempt to load bodies if we are generating code. If we
2014 -- are in semantics check only mode, then it would be wrong to load
2015 -- bodies that are not required from a semantic point of view, so
2016 -- in this case we return Empty. The result is that the caller may
2017 -- incorrectly decide that a generic spec does not have a body when
2018 -- in fact it does, but the only harm in this is that some warnings
2019 -- on elaboration problems may be lost in semantic checks only mode,
2020 -- which is not big loss. We also return Empty if we go for a body
2021 -- and it is not there.
2023 function Locate_Corresponding_Body
(PE
: Entity_Id
) return Node_Id
;
2024 -- PE is the entity for a package spec. This function locates the
2025 -- corresponding package body, returning Empty if none is found.
2026 -- The package body returned is fully parsed but may not yet be
2027 -- analyzed, so only syntactic fields should be referenced.
2033 function Find_Body_In
(E
: Entity_Id
; N
: Node_Id
) return Node_Id
is
2038 while Present
(Nod
) loop
2040 -- If we found the package body we are looking for, return it
2042 if Nkind
(Nod
) = N_Package_Body
2043 and then Chars
(Defining_Unit_Name
(Nod
)) = Chars
(E
)
2047 -- If we found the stub for the body, go after the subunit,
2048 -- loading it if necessary.
2050 elsif Nkind
(Nod
) = N_Package_Body_Stub
2051 and then Chars
(Defining_Identifier
(Nod
)) = Chars
(E
)
2053 if Present
(Library_Unit
(Nod
)) then
2054 return Unit
(Library_Unit
(Nod
));
2057 return Load_Package_Body
(Get_Unit_Name
(Nod
));
2060 -- If neither package body nor stub, keep looking on chain
2070 -----------------------
2071 -- Load_Package_Body --
2072 -----------------------
2074 function Load_Package_Body
(Nam
: Unit_Name_Type
) return Node_Id
is
2075 U
: Unit_Number_Type
;
2078 if Operating_Mode
/= Generate_Code
then
2091 return Unit
(Cunit
(U
));
2094 end Load_Package_Body
;
2096 -------------------------------
2097 -- Locate_Corresponding_Body --
2098 -------------------------------
2100 function Locate_Corresponding_Body
(PE
: Entity_Id
) return Node_Id
is
2101 Spec
: constant Node_Id
:= Declaration_Node
(PE
);
2102 Decl
: constant Node_Id
:= Parent
(Spec
);
2103 Scop
: constant Entity_Id
:= Scope
(PE
);
2107 if Is_Library_Level_Entity
(PE
) then
2109 -- If package is a library unit that requires a body, we have
2110 -- no choice but to go after that body because it might contain
2111 -- an optional body for the original generic package.
2113 if Unit_Requires_Body
(PE
) then
2115 -- Load the body. Note that we are a little careful here to
2116 -- use Spec to get the unit number, rather than PE or Decl,
2117 -- since in the case where the package is itself a library
2118 -- level instantiation, Spec will properly reference the
2119 -- generic template, which is what we really want.
2123 (Get_Body_Name
(Unit_Name
(Get_Source_Unit
(Spec
))));
2125 -- But if the package is a library unit that does NOT require
2126 -- a body, then no body is permitted, so we are sure that there
2127 -- is no body for the original generic package.
2133 -- Otherwise look and see if we are embedded in a further package
2135 elsif Is_Package
(Scop
) then
2137 -- If so, get the body of the enclosing package, and look in
2138 -- its package body for the package body we are looking for.
2140 PBody
:= Locate_Corresponding_Body
(Scop
);
2145 return Find_Body_In
(PE
, First
(Declarations
(PBody
)));
2148 -- If we are not embedded in a further package, then the body
2149 -- must be in the same declarative part as we are.
2152 return Find_Body_In
(PE
, Next
(Decl
));
2154 end Locate_Corresponding_Body
;
2156 -- Start of processing for Has_Generic_Body
2159 if Present
(Corresponding_Body
(Decl
)) then
2162 elsif Unit_Requires_Body
(Ent
) then
2165 -- Compilation units cannot have optional bodies
2167 elsif Is_Compilation_Unit
(Ent
) then
2170 -- Otherwise look at what scope we are in
2173 Scop
:= Scope
(Ent
);
2175 -- Case of entity is in other than a package spec, in this case
2176 -- the body, if present, must be in the same declarative part.
2178 if not Is_Package
(Scop
) then
2183 P
:= Declaration_Node
(Ent
);
2185 -- Declaration node may get us a spec, so if so, go to
2186 -- the parent declaration.
2188 while not Is_List_Member
(P
) loop
2192 return Present
(Find_Body_In
(Ent
, Next
(P
)));
2195 -- If the entity is in a package spec, then we have to locate
2196 -- the corresponding package body, and look there.
2200 PBody
: constant Node_Id
:= Locate_Corresponding_Body
(Scop
);
2208 (Find_Body_In
(Ent
, (First
(Declarations
(PBody
)))));
2213 end Has_Generic_Body
;
2215 -----------------------
2216 -- Insert_Elab_Check --
2217 -----------------------
2219 procedure Insert_Elab_Check
(N
: Node_Id
; C
: Node_Id
:= Empty
) is
2221 Loc
: constant Source_Ptr
:= Sloc
(N
);
2224 -- If expansion is disabled, do not generate any checks. Also
2225 -- skip checks if any subunits are missing because in either
2226 -- case we lack the full information that we need, and no object
2227 -- file will be created in any case.
2229 if not Expander_Active
or else Subunits_Missing
then
2233 -- If we have a generic instantiation, where Instance_Spec is set,
2234 -- then this field points to a generic instance spec that has
2235 -- been inserted before the instantiation node itself, so that
2236 -- is where we want to insert a check.
2238 if Nkind
(N
) in N_Generic_Instantiation
2239 and then Present
(Instance_Spec
(N
))
2241 Nod
:= Instance_Spec
(N
);
2246 -- If we are inserting at the top level, insert in Aux_Decls
2248 if Nkind
(Parent
(Nod
)) = N_Compilation_Unit
then
2250 ADN
: constant Node_Id
:= Aux_Decls_Node
(Parent
(Nod
));
2256 Make_Raise_Program_Error
(Loc
,
2257 Reason
=> PE_Access_Before_Elaboration
);
2260 Make_Raise_Program_Error
(Loc
,
2261 Condition
=> Make_Op_Not
(Loc
, C
),
2262 Reason
=> PE_Access_Before_Elaboration
);
2265 if No
(Declarations
(ADN
)) then
2266 Set_Declarations
(ADN
, New_List
(R
));
2268 Append_To
(Declarations
(ADN
), R
);
2274 -- Otherwise just insert before the node in question. However, if
2275 -- the context of the call has already been analyzed, an insertion
2276 -- will not work if it depends on subsequent expansion (e.g. a call in
2277 -- a branch of a short-circuit). In that case we replace the call with
2278 -- a conditional expression, or with a Raise if it is unconditional.
2279 -- Unfortunately this does not work if the call has a dynamic size,
2280 -- because gigi regards it as a dynamic-sized temporary. If such a call
2281 -- appears in a short-circuit expression, the elaboration check will be
2282 -- missed (rare enough ???). Otherwise, the code below inserts the check
2283 -- at the appropriate place before the call. Same applies in the even
2284 -- rarer case the return type has a known size but is unconstrained.
2287 if Nkind
(N
) = N_Function_Call
2288 and then Analyzed
(Parent
(N
))
2289 and then Size_Known_At_Compile_Time
(Etype
(N
))
2291 (not Has_Discriminants
(Etype
(N
))
2292 or else Is_Constrained
(Etype
(N
)))
2296 Typ
: constant Entity_Id
:= Etype
(N
);
2297 Chk
: constant Boolean := Do_Range_Check
(N
);
2299 R
: constant Node_Id
:=
2300 Make_Raise_Program_Error
(Loc
,
2301 Reason
=> PE_Access_Before_Elaboration
);
2311 Make_Conditional_Expression
(Loc
,
2312 Expressions
=> New_List
(C
, Relocate_Node
(N
), R
)));
2315 Analyze_And_Resolve
(N
, Typ
);
2317 -- If the original call requires a range check, so does the
2318 -- conditional expression.
2321 Enable_Range_Check
(N
);
2323 Set_Do_Range_Check
(N
, False);
2330 Make_Raise_Program_Error
(Loc
,
2331 Reason
=> PE_Access_Before_Elaboration
));
2334 Make_Raise_Program_Error
(Loc
,
2338 Reason
=> PE_Access_Before_Elaboration
));
2342 end Insert_Elab_Check
;
2348 procedure Output_Calls
(N
: Node_Id
) is
2351 function Is_Printable_Error_Name
(Nm
: Name_Id
) return Boolean;
2352 -- An internal function, used to determine if a name, Nm, is either
2353 -- a non-internal name, or is an internal name that is printable
2354 -- by the error message circuits (i.e. it has a single upper
2355 -- case letter at the end).
2357 function Is_Printable_Error_Name
(Nm
: Name_Id
) return Boolean is
2359 if not Is_Internal_Name
(Nm
) then
2362 elsif Name_Len
= 1 then
2366 Name_Len
:= Name_Len
- 1;
2367 return not Is_Internal_Name
;
2369 end Is_Printable_Error_Name
;
2371 -- Start of processing for Output_Calls
2374 for J
in reverse 1 .. Elab_Call
.Last
loop
2375 Error_Msg_Sloc
:= Elab_Call
.Table
(J
).Cloc
;
2377 Ent
:= Elab_Call
.Table
(J
).Ent
;
2379 if Is_Generic_Unit
(Ent
) then
2380 Error_Msg_NE
("\?& instantiated #", N
, Ent
);
2382 elsif Is_Init_Proc
(Ent
) then
2383 Error_Msg_N
("\?initialization procedure called #", N
);
2385 elsif Is_Printable_Error_Name
(Chars
(Ent
)) then
2386 Error_Msg_NE
("\?& called #", N
, Ent
);
2389 Error_Msg_N
("\? called #", N
);
2394 ----------------------------
2395 -- Same_Elaboration_Scope --
2396 ----------------------------
2398 function Same_Elaboration_Scope
(Scop1
, Scop2
: Entity_Id
) return Boolean is
2399 S1
: Entity_Id
:= Scop1
;
2400 S2
: Entity_Id
:= Scop2
;
2403 while S1
/= Standard_Standard
2404 and then (Ekind
(S1
) = E_Package
2406 Ekind
(S1
) = E_Block
)
2411 while S2
/= Standard_Standard
2412 and then (Ekind
(S2
) = E_Package
2414 Ekind
(S2
) = E_Protected_Type
2416 Ekind
(S2
) = E_Block
)
2422 end Same_Elaboration_Scope
;
2428 procedure Set_C_Scope
is
2430 while not Is_Compilation_Unit
(C_Scope
) loop
2431 C_Scope
:= Scope
(C_Scope
);
2439 function Spec_Entity
(E
: Entity_Id
) return Entity_Id
is
2443 -- Check for case of body entity
2444 -- Why is the check for E_Void needed???
2446 if Ekind
(E
) = E_Void
2447 or else Ekind
(E
) = E_Subprogram_Body
2448 or else Ekind
(E
) = E_Package_Body
2453 Decl
:= Parent
(Decl
);
2454 exit when Nkind
(Decl
) in N_Proper_Body
;
2457 return Corresponding_Spec
(Decl
);
2468 procedure Supply_Bodies
(N
: Node_Id
) is
2470 if Nkind
(N
) = N_Subprogram_Declaration
then
2472 Ent
: constant Entity_Id
:= Defining_Unit_Name
(Specification
(N
));
2475 Set_Is_Imported
(Ent
);
2476 Set_Convention
(Ent
, Convention_Stubbed
);
2479 elsif Nkind
(N
) = N_Package_Declaration
then
2481 Spec
: constant Node_Id
:= Specification
(N
);
2484 New_Scope
(Defining_Unit_Name
(Spec
));
2485 Supply_Bodies
(Visible_Declarations
(Spec
));
2486 Supply_Bodies
(Private_Declarations
(Spec
));
2492 procedure Supply_Bodies
(L
: List_Id
) is
2498 while Present
(Elmt
) loop
2499 Supply_Bodies
(Elmt
);
2509 function Within
(E1
, E2
: Entity_Id
) return Boolean is
2519 elsif Scop
= Standard_Standard
then
2523 Scop
:= Scope
(Scop
);
2527 raise Program_Error
;
2530 --------------------------
2531 -- Within_Elaborate_All --
2532 --------------------------
2534 function Within_Elaborate_All
(E
: Entity_Id
) return Boolean is
2537 Elab_Id
: Entity_Id
;
2541 Item
:= First
(Context_Items
(Cunit
(Current_Sem_Unit
)));
2543 while Present
(Item
) loop
2544 if Nkind
(Item
) = N_Pragma
2545 and then Get_Pragma_Id
(Chars
(Item
)) = Pragma_Elaborate_All
2547 if Error_Posted
(Item
) then
2549 -- Some previous error on the pragma itself
2556 Expression
(First
(Pragma_Argument_Associations
(Item
))));
2558 Par
:= Parent
(Unit_Declaration_Node
(Elab_Id
));
2559 Item2
:= First
(Context_Items
(Par
));
2561 while Present
(Item2
) loop
2562 if Nkind
(Item2
) = N_With_Clause
2563 and then Entity
(Name
(Item2
)) = E
2576 end Within_Elaborate_All
;