1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1997-2012, 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 3, 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 COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree
; use Atree
;
27 with Checks
; use Checks
;
28 with Debug
; use Debug
;
29 with Einfo
; use Einfo
;
30 with Elists
; use Elists
;
31 with Errout
; use Errout
;
32 with Exp_Tss
; use Exp_Tss
;
33 with Exp_Util
; use Exp_Util
;
34 with Expander
; use Expander
;
35 with Fname
; use Fname
;
37 with Lib
.Load
; use Lib
.Load
;
38 with Namet
; use Namet
;
39 with Nlists
; use Nlists
;
40 with Nmake
; use Nmake
;
42 with Output
; use Output
;
43 with Restrict
; use Restrict
;
44 with Rident
; use Rident
;
46 with Sem_Aux
; use Sem_Aux
;
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_Type
; use Sem_Type
;
52 with Sem_Util
; use Sem_Util
;
53 with Sinfo
; use Sinfo
;
54 with Sinput
; use Sinput
;
55 with Snames
; use Snames
;
56 with Stand
; use Stand
;
58 with Tbuild
; use Tbuild
;
59 with Uintp
; use Uintp
;
60 with Uname
; use Uname
;
62 package body Sem_Elab
is
64 -- The following table records the recursive call chain for output in the
65 -- Output routine. Each entry records the call node and the entity of the
66 -- called routine. The number of entries in the table (i.e. the value of
67 -- Elab_Call.Last) indicates the current depth of recursion and is used to
68 -- identify the outer level.
70 type Elab_Call_Entry
is record
75 package Elab_Call
is new Table
.Table
(
76 Table_Component_Type
=> Elab_Call_Entry
,
77 Table_Index_Type
=> Int
,
80 Table_Increment
=> 100,
81 Table_Name
=> "Elab_Call");
83 -- This table is initialized at the start of each outer level call. It
84 -- holds the entities for all subprograms that have been examined for this
85 -- particular outer level call, and is used to prevent both infinite
86 -- recursion, and useless reanalysis of bodies already seen
88 package Elab_Visited
is new Table
.Table
(
89 Table_Component_Type
=> Entity_Id
,
90 Table_Index_Type
=> Int
,
93 Table_Increment
=> 100,
94 Table_Name
=> "Elab_Visited");
96 -- This table stores calls to Check_Internal_Call that are delayed
97 -- until all generics are instantiated, and in particular that all
98 -- generic bodies have been inserted. We need to delay, because we
99 -- need to be able to look through the inserted bodies.
101 type Delay_Element
is record
103 -- The parameter N from the call to Check_Internal_Call. Note that
104 -- this node may get rewritten over the delay period by expansion
105 -- in the call case (but not in the instantiation case).
108 -- The parameter E from the call to Check_Internal_Call
110 Orig_Ent
: Entity_Id
;
111 -- The parameter Orig_Ent from the call to Check_Internal_Call
114 -- The current scope of the call. This is restored when we complete
115 -- the delayed call, so that we do this in the right scope.
117 From_Elab_Code
: Boolean;
118 -- Save indication of whether this call is from elaboration code
120 Outer_Scope
: Entity_Id
;
121 -- Save scope of outer level call
124 package Delay_Check
is new Table
.Table
(
125 Table_Component_Type
=> Delay_Element
,
126 Table_Index_Type
=> Int
,
127 Table_Low_Bound
=> 1,
128 Table_Initial
=> 1000,
129 Table_Increment
=> 100,
130 Table_Name
=> "Delay_Check");
133 -- Top level scope of current scope. Compute this only once at the outer
134 -- level, i.e. for a call to Check_Elab_Call from 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 called,
155 -- the delay table is used to make the delayed calls and this flag is reset
156 -- to False, so that the calls are processed
158 -----------------------
159 -- Local Subprograms --
160 -----------------------
162 -- Note: Outer_Scope in all following specs 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 Activate_Elaborate_All_Desirable
(N
: Node_Id
; U
: Entity_Id
);
170 -- Analysis of construct N shows that we should set Elaborate_All_Desirable
171 -- for the WITH clause for unit U (which will always be present). A special
172 -- case is when N is a function or procedure instantiation, in which case
173 -- it is sufficient to set Elaborate_Desirable, since in this case there is
174 -- no possibility of transitive elaboration issues.
176 procedure Check_A_Call
179 Outer_Scope
: Entity_Id
;
180 Inter_Unit_Only
: Boolean;
181 Generate_Warnings
: Boolean := True;
182 In_Init_Proc
: Boolean := False);
183 -- This is the internal recursive routine that is called to check for
184 -- possible elaboration error. The argument N is a subprogram call or
185 -- generic instantiation, or 'Access attribute reference to be checked, and
186 -- E is the entity of the called subprogram, or instantiated generic unit,
187 -- or subprogram referenced by 'Access.
189 -- The flag Outer_Scope is the outer level scope for the original call.
190 -- Inter_Unit_Only is set if the call is only to be checked in the
191 -- case where it is to another unit (and skipped if within a unit).
192 -- Generate_Warnings is set to False to suppress warning messages about
193 -- missing pragma Elaborate_All's. These messages are not wanted for
194 -- inner calls in the dynamic model. Note that an instance of the Access
195 -- attribute applied to a subprogram also generates a call to this
196 -- procedure (since the referenced subprogram may be called later
197 -- indirectly). Flag In_Init_Proc should be set whenever the current
198 -- context is a type init proc.
200 procedure Check_Bad_Instantiation
(N
: Node_Id
);
201 -- N is a node for an instantiation (if called with any other node kind,
202 -- Check_Bad_Instantiation ignores the call). This subprogram checks for
203 -- the special case of a generic instantiation of a generic spec in the
204 -- same declarative part as the instantiation where a body is present and
205 -- has not yet been seen. This is an obvious error, but needs to be checked
206 -- specially at the time of the instantiation, since it is a case where we
207 -- cannot insert the body anywhere. If this case is detected, warnings are
208 -- generated, and a raise of Program_Error is inserted. In addition any
209 -- subprograms in the generic spec are stubbed, and the Bad_Instantiation
210 -- flag is set on the instantiation node. The caller in Sem_Ch12 uses this
211 -- flag as an indication that no attempt should be made to insert an
214 procedure Check_Internal_Call
217 Outer_Scope
: Entity_Id
;
218 Orig_Ent
: Entity_Id
);
219 -- N is a function call or procedure statement call node and E is the
220 -- entity of the called function, which is within the current compilation
221 -- unit (where subunits count as part of the parent). This call checks if
222 -- this call, or any call within any accessed body could cause an ABE, and
223 -- if so, outputs a warning. Orig_Ent differs from E only in the case of
224 -- renamings, and points to the original name of the entity. This is used
225 -- for error messages. Outer_Scope is the outer level scope for the
228 procedure Check_Internal_Call_Continue
231 Outer_Scope
: Entity_Id
;
232 Orig_Ent
: Entity_Id
);
233 -- The processing for Check_Internal_Call is divided up into two phases,
234 -- and this represents the second phase. The second phase is delayed if
235 -- Delaying_Elab_Calls is set to True. In this delayed case, the first
236 -- phase makes an entry in the Delay_Check table, which is processed when
237 -- Check_Elab_Calls is called. N, E and Orig_Ent are as for the call to
238 -- Check_Internal_Call. Outer_Scope is the outer level scope for the
241 function Has_Generic_Body
(N
: Node_Id
) return Boolean;
242 -- N is a generic package instantiation node, and this routine determines
243 -- if this package spec does in fact have a generic body. If so, then
244 -- True is returned, otherwise False. Note that this is not at all the
245 -- same as checking if the unit requires a body, since it deals with
246 -- the case of optional bodies accurately (i.e. if a body is optional,
247 -- then it looks to see if a body is actually present). Note: this
248 -- function can only do a fully correct job if in generating code mode
249 -- where all bodies have to be present. If we are operating in semantics
250 -- check only mode, then in some cases of optional bodies, a result of
251 -- False may incorrectly be given. In practice this simply means that
252 -- some cases of warnings for incorrect order of elaboration will only
253 -- be given when generating code, which is not a big problem (and is
254 -- inevitable, given the optional body semantics of Ada).
256 procedure Insert_Elab_Check
(N
: Node_Id
; C
: Node_Id
:= Empty
);
257 -- Given code for an elaboration check (or unconditional raise if the check
258 -- is not needed), inserts the code in the appropriate place. N is the call
259 -- or instantiation node for which the check code is required. C is the
260 -- test whose failure triggers the raise.
262 function Is_Finalization_Procedure
(Id
: Entity_Id
) return Boolean;
263 -- Determine whether entity Id denotes a [Deep_]Finalize procedure
265 procedure Output_Calls
(N
: Node_Id
);
266 -- Outputs chain of calls stored in the Elab_Call table. The caller has
267 -- already generated the main warning message, so the warnings generated
268 -- are all continuation messages. The argument is the call node at which
269 -- the messages are to be placed.
271 function Same_Elaboration_Scope
(Scop1
, Scop2
: Entity_Id
) return Boolean;
272 -- Given two scopes, determine whether they are the same scope from an
273 -- elaboration point of view, i.e. packages and blocks are ignored.
275 procedure Set_C_Scope
;
276 -- On entry C_Scope is set to some scope. On return, C_Scope is reset
277 -- to be the enclosing compilation unit of this scope.
279 function Get_Referenced_Ent
(N
: Node_Id
) return Entity_Id
;
280 -- N is either a function or procedure call or an access attribute that
281 -- references a subprogram. This call retrieves the relevant entity. If
282 -- this is a call to a protected subprogram, the entity is a selected
283 -- component. The callable entity may be absent, in which case Empty is
284 -- returned. This happens with non-analyzed calls in nested generics.
286 procedure Set_Elaboration_Constraint
290 -- The current unit U may depend semantically on some unit P which is not
291 -- in the current context. If there is an elaboration call that reaches P,
292 -- we need to indicate that P requires an Elaborate_All, but this is not
293 -- effective in U's ali file, if there is no with_clause for P. In this
294 -- case we add the Elaborate_All on the unit Q that directly or indirectly
295 -- makes P available. This can happen in two cases:
297 -- a) Q declares a subtype of a type declared in P, and the call is an
298 -- initialization call for an object of that subtype.
300 -- b) Q declares an object of some tagged type whose root type is
301 -- declared in P, and the initialization call uses object notation on
302 -- that object to reach a primitive operation or a classwide operation
305 -- If P appears in the context of U, the current processing is correct.
306 -- Otherwise we must identify these two cases to retrieve Q and place the
307 -- Elaborate_All_Desirable on it.
309 function Spec_Entity
(E
: Entity_Id
) return Entity_Id
;
310 -- Given a compilation unit entity, if it is a spec entity, it is returned
311 -- unchanged. If it is a body entity, then the spec for the corresponding
314 procedure Supply_Bodies
(N
: Node_Id
);
315 -- Given a node, N, that is either a subprogram declaration or a package
316 -- declaration, this procedure supplies dummy bodies for the subprogram
317 -- or for all subprograms in the package. If the given node is not one
318 -- of these two possibilities, then Supply_Bodies does nothing. The
319 -- dummy body contains a single Raise statement.
321 procedure Supply_Bodies
(L
: List_Id
);
322 -- Calls Supply_Bodies for all elements of the given list L
324 function Within
(E1
, E2
: Entity_Id
) return Boolean;
325 -- Given two scopes E1 and E2, returns True if E1 is equal to E2, or is one
326 -- of its contained scopes, False otherwise.
328 function Within_Elaborate_All
329 (Unit
: Unit_Number_Type
;
330 E
: Entity_Id
) return Boolean;
331 -- Return True if we are within the scope of an Elaborate_All for E, or if
332 -- we are within the scope of an Elaborate_All for some other unit U, and U
333 -- with's E. This prevents spurious warnings when the called entity is
334 -- renamed within U, or in case of generic instances.
336 --------------------------------------
337 -- Activate_Elaborate_All_Desirable --
338 --------------------------------------
340 procedure Activate_Elaborate_All_Desirable
(N
: Node_Id
; U
: Entity_Id
) is
341 UN
: constant Unit_Number_Type
:= Get_Code_Unit
(N
);
342 CU
: constant Node_Id
:= Cunit
(UN
);
343 UE
: constant Entity_Id
:= Cunit_Entity
(UN
);
344 Unm
: constant Unit_Name_Type
:= Unit_Name
(UN
);
345 CI
: constant List_Id
:= Context_Items
(CU
);
349 procedure Add_To_Context_And_Mark
(Itm
: Node_Id
);
350 -- This procedure is called when the elaborate indication must be
351 -- applied to a unit not in the context of the referencing unit. The
352 -- unit gets added to the context as an implicit with.
354 function In_Withs_Of
(UEs
: Entity_Id
) return Boolean;
355 -- UEs is the spec entity of a unit. If the unit to be marked is
356 -- in the context item list of this unit spec, then the call returns
357 -- True and Itm is left set to point to the relevant N_With_Clause node.
359 procedure Set_Elab_Flag
(Itm
: Node_Id
);
360 -- Sets Elaborate_[All_]Desirable as appropriate on Itm
362 -----------------------------
363 -- Add_To_Context_And_Mark --
364 -----------------------------
366 procedure Add_To_Context_And_Mark
(Itm
: Node_Id
) is
367 CW
: constant Node_Id
:=
368 Make_With_Clause
(Sloc
(Itm
),
372 Set_Library_Unit
(CW
, Library_Unit
(Itm
));
373 Set_Implicit_With
(CW
, True);
375 -- Set elaborate all desirable on copy and then append the copy to
376 -- the list of body with's and we are done.
380 end Add_To_Context_And_Mark
;
386 function In_Withs_Of
(UEs
: Entity_Id
) return Boolean is
387 UNs
: constant Unit_Number_Type
:= Get_Source_Unit
(UEs
);
388 CUs
: constant Node_Id
:= Cunit
(UNs
);
389 CIs
: constant List_Id
:= Context_Items
(CUs
);
393 while Present
(Itm
) loop
394 if Nkind
(Itm
) = N_With_Clause
then
396 Cunit_Entity
(Get_Cunit_Unit_Number
(Library_Unit
(Itm
)));
413 procedure Set_Elab_Flag
(Itm
: Node_Id
) is
415 if Nkind
(N
) in N_Subprogram_Instantiation
then
416 Set_Elaborate_Desirable
(Itm
);
418 Set_Elaborate_All_Desirable
(Itm
);
422 -- Start of processing for Activate_Elaborate_All_Desirable
425 -- Do not set binder indication if expansion is disabled, as when
426 -- compiling a generic unit.
428 if not Expander_Active
then
433 while Present
(Itm
) loop
434 if Nkind
(Itm
) = N_With_Clause
then
435 Ent
:= Cunit_Entity
(Get_Cunit_Unit_Number
(Library_Unit
(Itm
)));
437 -- If we find it, then mark elaborate all desirable and return
448 -- If we fall through then the with clause is not present in the
449 -- current unit. One legitimate possibility is that the with clause
450 -- is present in the spec when we are a body.
452 if Is_Body_Name
(Unm
)
453 and then In_Withs_Of
(Spec_Entity
(UE
))
455 Add_To_Context_And_Mark
(Itm
);
459 -- Similarly, we may be in the spec or body of a child unit, where
460 -- the unit in question is with'ed by some ancestor of the child unit.
462 if Is_Child_Name
(Unm
) then
470 exit when Pkg
= Standard_Standard
;
472 if In_Withs_Of
(Pkg
) then
473 Add_To_Context_And_Mark
(Itm
);
480 -- Here if we do not find with clause on spec or body. We just ignore
481 -- this case, it means that the elaboration involves some other unit
482 -- than the unit being compiled, and will be caught elsewhere.
485 end Activate_Elaborate_All_Desirable
;
491 procedure Check_A_Call
494 Outer_Scope
: Entity_Id
;
495 Inter_Unit_Only
: Boolean;
496 Generate_Warnings
: Boolean := True;
497 In_Init_Proc
: Boolean := False)
499 Loc
: constant Source_Ptr
:= Sloc
(N
);
504 -- Top level scope of entity for called subprogram. This value includes
505 -- following renamings and derivations, so this scope can be in a
506 -- non-visible unit. This is the scope that is to be investigated to
507 -- see whether an elaboration check is required.
510 -- Top level scope of directly called entity for subprogram. This
511 -- differs from E_Scope in the case where renamings or derivations
512 -- are involved, since it does not follow these links. W_Scope is
513 -- generally in a visible unit, and it is this scope that may require
514 -- an Elaborate_All. However, there are some cases (initialization
515 -- calls and calls involving object notation) where W_Scope might not
516 -- be in the context of the current unit, and there is an intermediate
517 -- package that is, in which case the Elaborate_All has to be placed
518 -- on this intermediate package. These special cases are handled in
519 -- Set_Elaboration_Constraint.
521 Body_Acts_As_Spec
: Boolean;
522 -- Set to true if call is to body acting as spec (no separate spec)
524 Inst_Case
: constant Boolean := Nkind
(N
) in N_Generic_Instantiation
;
525 -- Indicates if we have instantiation case
527 Access_Case
: constant Boolean := Nkind
(N
) = N_Attribute_Reference
;
528 -- Indicates if we have Access attribute case
530 Caller_Unit_Internal
: Boolean;
531 Callee_Unit_Internal
: Boolean;
533 Inst_Caller
: Source_Ptr
;
534 Inst_Callee
: Source_Ptr
;
536 Unit_Caller
: Unit_Number_Type
;
537 Unit_Callee
: Unit_Number_Type
;
539 Cunit_SC
: Boolean := False;
540 -- Set to suppress dynamic elaboration checks where one of the
541 -- enclosing scopes has Elaboration_Checks_Suppressed set, or else
542 -- if a pragma Elaborate (_All) applies to that scope, in which case
543 -- warnings on the scope are also suppressed. For the internal case,
544 -- we ignore this flag.
547 -- If the call is known to be within a local Suppress Elaboration
548 -- pragma, nothing to check. This can happen in task bodies.
550 if Nkind
(N
) in N_Subprogram_Call
551 and then No_Elaboration_Check
(N
)
556 -- Go to parent for derived subprogram, or to original subprogram in the
557 -- case of a renaming (Alias covers both these cases).
561 if (Suppress_Elaboration_Warnings
(Ent
)
562 or else Elaboration_Checks_Suppressed
(Ent
))
563 and then (Inst_Case
or else No
(Alias
(Ent
)))
568 -- Nothing to do for imported entities
570 if Is_Imported
(Ent
) then
574 exit when Inst_Case
or else No
(Alias
(Ent
));
578 Decl
:= Unit_Declaration_Node
(Ent
);
580 if Nkind
(Decl
) = N_Subprogram_Body
then
581 Body_Acts_As_Spec
:= True;
583 elsif Nkind
(Decl
) = N_Subprogram_Declaration
584 or else Nkind
(Decl
) = N_Subprogram_Body_Stub
587 Body_Acts_As_Spec
:= False;
589 -- If we have none of an instantiation, subprogram body or
590 -- subprogram declaration, then it is not a case that we want
591 -- to check. (One case is a call to a generic formal subprogram,
592 -- where we do not want the check in the template).
600 if Elaboration_Checks_Suppressed
(E_Scope
)
601 or else Suppress_Elaboration_Warnings
(E_Scope
)
606 -- Exit when we get to compilation unit, not counting subunits
608 exit when Is_Compilation_Unit
(E_Scope
)
609 and then (Is_Child_Unit
(E_Scope
)
610 or else Scope
(E_Scope
) = Standard_Standard
);
612 -- If we did not find a compilation unit, other than standard,
613 -- then nothing to check (happens in some instantiation cases)
615 if E_Scope
= Standard_Standard
then
618 -- Otherwise move up a scope looking for compilation unit
621 E_Scope
:= Scope
(E_Scope
);
625 -- No checks needed for pure or preelaborated compilation units
627 if Is_Pure
(E_Scope
) or else Is_Preelaborated
(E_Scope
) then
631 -- If the generic entity is within a deeper instance than we are, then
632 -- either the instantiation to which we refer itself caused an ABE, in
633 -- which case that will be handled separately, or else we know that the
634 -- body we need appears as needed at the point of the instantiation.
635 -- However, this assumption is only valid if we are in static mode.
637 if not Dynamic_Elaboration_Checks
638 and then Instantiation_Depth
(Sloc
(Ent
)) >
639 Instantiation_Depth
(Sloc
(N
))
644 -- Do not give a warning for a package with no body
646 if Ekind
(Ent
) = E_Generic_Package
647 and then not Has_Generic_Body
(N
)
652 -- Case of entity is not in current unit (i.e. with'ed unit case)
654 if E_Scope
/= C_Scope
then
656 -- We are only interested in such calls if the outer call was from
657 -- elaboration code, or if we are in Dynamic_Elaboration_Checks mode.
659 if not From_Elab_Code
and then not Dynamic_Elaboration_Checks
then
663 -- Nothing to do if some scope said that no checks were required
669 -- Nothing to do for a generic instance, because in this case the
670 -- checking was at the point of instantiation of the generic However,
671 -- this shortcut is only applicable in static mode.
673 if Is_Generic_Instance
(Ent
) and not Dynamic_Elaboration_Checks
then
677 -- Nothing to do if subprogram with no separate spec. However, a
678 -- call to Deep_Initialize may result in a call to a user-defined
679 -- Initialize procedure, which imposes a body dependency. This
680 -- happens only if the type is controlled and the Initialize
681 -- procedure is not inherited.
683 if Body_Acts_As_Spec
then
684 if Is_TSS
(Ent
, TSS_Deep_Initialize
) then
686 Typ
: constant Entity_Id
:= Etype
(First_Formal
(Ent
));
690 if not Is_Controlled
(Typ
) then
693 Init
:= Find_Prim_Op
(Typ
, Name_Initialize
);
695 if Comes_From_Source
(Init
) then
708 -- Check cases of internal units
710 Callee_Unit_Internal
:=
711 Is_Internal_File_Name
712 (Unit_File_Name
(Get_Source_Unit
(E_Scope
)));
714 -- Do not give a warning if the with'ed unit is internal and this is
715 -- the generic instantiation case (this saves a lot of hassle dealing
716 -- with the Text_IO special child units)
718 if Callee_Unit_Internal
and Inst_Case
then
722 if C_Scope
= Standard_Standard
then
723 Caller_Unit_Internal
:= False;
725 Caller_Unit_Internal
:=
726 Is_Internal_File_Name
727 (Unit_File_Name
(Get_Source_Unit
(C_Scope
)));
730 -- Do not give a warning if the with'ed unit is internal and the
731 -- caller is not internal (since the binder always elaborates
732 -- internal units first).
734 if Callee_Unit_Internal
and (not Caller_Unit_Internal
) then
738 -- For now, if debug flag -gnatdE is not set, do no checking for
739 -- one internal unit withing another. This fixes the problem with
740 -- the sgi build and storage errors. To be resolved later ???
742 if (Callee_Unit_Internal
and Caller_Unit_Internal
)
743 and then not Debug_Flag_EE
748 if Is_TSS
(E
, TSS_Deep_Initialize
) then
752 -- If the call is in an instance, and the called entity is not
753 -- defined in the same instance, then the elaboration issue focuses
754 -- around the unit containing the template, it is this unit which
755 -- requires an Elaborate_All.
757 -- However, if we are doing dynamic elaboration, we need to chase the
758 -- call in the usual manner.
760 -- We do not handle the case of calling a generic formal correctly in
761 -- the static case.???
763 Inst_Caller
:= Instantiation
(Get_Source_File_Index
(Sloc
(N
)));
764 Inst_Callee
:= Instantiation
(Get_Source_File_Index
(Sloc
(Ent
)));
766 if Inst_Caller
= No_Location
then
767 Unit_Caller
:= No_Unit
;
769 Unit_Caller
:= Get_Source_Unit
(N
);
772 if Inst_Callee
= No_Location
then
773 Unit_Callee
:= No_Unit
;
775 Unit_Callee
:= Get_Source_Unit
(Ent
);
778 if Unit_Caller
/= No_Unit
779 and then Unit_Callee
/= Unit_Caller
780 and then not Dynamic_Elaboration_Checks
782 E_Scope
:= Spec_Entity
(Cunit_Entity
(Unit_Caller
));
784 -- If we don't get a spec entity, just ignore call. Not quite
785 -- clear why this check is necessary. ???
791 -- Otherwise step to enclosing compilation unit
793 while not Is_Compilation_Unit
(E_Scope
) loop
794 E_Scope
:= Scope
(E_Scope
);
797 -- For the case N is not an instance, or a call within instance, we
798 -- recompute E_Scope for the error message, since we do NOT want to
799 -- go to the unit which has the ultimate declaration in the case of
800 -- renaming and derivation and we also want to go to the generic unit
801 -- in the case of an instance, and no further.
804 -- Loop to carefully follow renamings and derivations one step
805 -- outside the current unit, but not further.
808 and then Present
(Alias
(Ent
))
810 E_Scope
:= Alias
(Ent
);
816 while not Is_Compilation_Unit
(E_Scope
) loop
817 E_Scope
:= Scope
(E_Scope
);
820 -- If E_Scope is the same as C_Scope, it means that there
821 -- definitely was a local renaming or derivation, and we
822 -- are not yet out of the current unit.
824 exit when E_Scope
/= C_Scope
;
828 -- If no alias, there is a previous error
836 if Within_Elaborate_All
(Current_Sem_Unit
, E_Scope
) then
840 -- Find top level scope for called entity (not following renamings
841 -- or derivations). This is where the Elaborate_All will go if it
842 -- is needed. We start with the called entity, except in the case
843 -- of an initialization procedure outside the current package, where
844 -- the init proc is in the root package, and we start from the entity
845 -- of the name in the call.
848 Ent
: constant Entity_Id
:= Get_Referenced_Ent
(N
);
850 if Is_Init_Proc
(Ent
)
851 and then not In_Same_Extended_Unit
(N
, Ent
)
853 W_Scope
:= Scope
(Ent
);
859 -- Now loop through scopes to get to the enclosing compilation unit
861 while not Is_Compilation_Unit
(W_Scope
) loop
862 W_Scope
:= Scope
(W_Scope
);
865 -- Now check if an elaborate_all (or dynamic check) is needed
867 if not Suppress_Elaboration_Warnings
(Ent
)
868 and then not Elaboration_Checks_Suppressed
(Ent
)
869 and then not Suppress_Elaboration_Warnings
(E_Scope
)
870 and then not Elaboration_Checks_Suppressed
(E_Scope
)
871 and then Elab_Warnings
872 and then Generate_Warnings
874 Generate_Elab_Warnings
: declare
875 procedure Elab_Warning
878 Ent
: Node_Or_Entity_Id
);
879 -- Generate a call to Error_Msg_NE with parameters Msg_D or
880 -- Msg_S (for dynamic or static elaboration model), N and Ent.
881 -- Msg_D is suppressed for the attribute reference case, since
882 -- we never raise Program_Error for an attribute reference.
888 procedure Elab_Warning
891 Ent
: Node_Or_Entity_Id
)
894 if Dynamic_Elaboration_Checks
then
895 if not Access_Case
then
896 Error_Msg_NE
(Msg_D
, N
, Ent
);
899 Error_Msg_NE
(Msg_S
, N
, Ent
);
903 -- Start of processing for Generate_Elab_Warnings
906 -- Instantiation case
910 ("instantiation of& may raise Program_Error?",
911 "info: instantiation of& during elaboration?", Ent
);
913 -- Indirect call case, warning only in static elaboration
914 -- case, because the attribute reference itself cannot raise
917 elsif Access_Case
then
919 ("", "info: access to& during elaboration?", Ent
);
921 -- Subprogram call case
924 if Nkind
(Name
(N
)) in N_Has_Entity
925 and then Is_Init_Proc
(Entity
(Name
(N
)))
926 and then Comes_From_Source
(Ent
)
929 ("implicit call to & may raise Program_Error?",
930 "info: implicit call to & during elaboration?",
935 ("call to & may raise Program_Error?",
936 "info: call to & during elaboration?",
941 Error_Msg_Qual_Level
:= Nat
'Last;
943 if Nkind
(N
) in N_Subprogram_Instantiation
then
945 ("\missing pragma Elaborate for&?",
946 "\info: implicit pragma Elaborate for& generated?",
951 ("\missing pragma Elaborate_All for&?",
952 "\info: implicit pragma Elaborate_All for & generated?",
955 end Generate_Elab_Warnings
;
957 Error_Msg_Qual_Level
:= 0;
960 -- Set flag to prevent further warnings for same unit unless in
963 if not All_Errors_Mode
and not Dynamic_Elaboration_Checks
then
964 Set_Suppress_Elaboration_Warnings
(W_Scope
, True);
968 -- Check for runtime elaboration check required
970 if Dynamic_Elaboration_Checks
then
971 if not Elaboration_Checks_Suppressed
(Ent
)
972 and then not Elaboration_Checks_Suppressed
(W_Scope
)
973 and then not Elaboration_Checks_Suppressed
(E_Scope
)
974 and then not Cunit_SC
976 -- Runtime elaboration check required. Generate check of the
977 -- elaboration Boolean for the unit containing the entity.
979 -- Note that for this case, we do check the real unit (the one
980 -- from following renamings, since that is the issue!)
982 -- Could this possibly miss a useless but required PE???
984 Insert_Elab_Check
(N
,
985 Make_Attribute_Reference
(Loc
,
986 Attribute_Name
=> Name_Elaborated
,
988 New_Occurrence_Of
(Spec_Entity
(E_Scope
), Loc
)));
990 -- Prevent duplicate elaboration checks on the same call,
991 -- which can happen if the body enclosing the call appears
992 -- itself in a call whose elaboration check is delayed.
994 if Nkind
(N
) in N_Subprogram_Call
then
995 Set_No_Elaboration_Check
(N
);
999 -- Case of static elaboration model
1002 -- Do not do anything if elaboration checks suppressed. Note that
1003 -- we check Ent here, not E, since we want the real entity for the
1004 -- body to see if checks are suppressed for it, not the dummy
1005 -- entry for renamings or derivations.
1007 if Elaboration_Checks_Suppressed
(Ent
)
1008 or else Elaboration_Checks_Suppressed
(E_Scope
)
1009 or else Elaboration_Checks_Suppressed
(W_Scope
)
1013 -- Do not generate an Elaborate_All for finalization routines
1014 -- which perform partial clean up as part of initialization.
1016 elsif In_Init_Proc
and then Is_Finalization_Procedure
(Ent
) then
1019 -- Here we need to generate an implicit elaborate all
1022 -- Generate elaborate_all warning unless suppressed
1024 if (Elab_Warnings
and Generate_Warnings
and not Inst_Case
)
1025 and then not Suppress_Elaboration_Warnings
(Ent
)
1026 and then not Suppress_Elaboration_Warnings
(E_Scope
)
1027 and then not Suppress_Elaboration_Warnings
(W_Scope
)
1029 Error_Msg_Node_2
:= W_Scope
;
1031 ("call to& in elaboration code " &
1032 "requires pragma Elaborate_All on&?", N
, E
);
1035 -- Set indication for binder to generate Elaborate_All
1037 Set_Elaboration_Constraint
(N
, E
, W_Scope
);
1041 -- Case of entity is in same unit as call or instantiation
1043 elsif not Inter_Unit_Only
then
1044 Check_Internal_Call
(N
, Ent
, Outer_Scope
, E
);
1048 -----------------------------
1049 -- Check_Bad_Instantiation --
1050 -----------------------------
1052 procedure Check_Bad_Instantiation
(N
: Node_Id
) is
1056 -- Nothing to do if we do not have an instantiation (happens in some
1057 -- error cases, and also in the formal package declaration case)
1059 if Nkind
(N
) not in N_Generic_Instantiation
then
1062 -- Nothing to do if serious errors detected (avoid cascaded errors)
1064 elsif Serious_Errors_Detected
/= 0 then
1067 -- Nothing to do if not in full analysis mode
1069 elsif not Full_Analysis
then
1072 -- Nothing to do if inside a generic template
1074 elsif Inside_A_Generic
then
1077 -- Nothing to do if a library level instantiation
1079 elsif Nkind
(Parent
(N
)) = N_Compilation_Unit
then
1082 -- Nothing to do if we are compiling a proper body for semantic
1083 -- purposes only. The generic body may be in another proper body.
1086 Nkind
(Parent
(Unit_Declaration_Node
(Main_Unit_Entity
))) = N_Subunit
1091 Ent
:= Get_Generic_Entity
(N
);
1093 -- The case we are interested in is when the generic spec is in the
1094 -- current declarative part
1096 if not Same_Elaboration_Scope
(Current_Scope
, Scope
(Ent
))
1097 or else not In_Same_Extended_Unit
(N
, Ent
)
1102 -- If the generic entity is within a deeper instance than we are, then
1103 -- either the instantiation to which we refer itself caused an ABE, in
1104 -- which case that will be handled separately. Otherwise, we know that
1105 -- the body we need appears as needed at the point of the instantiation.
1106 -- If they are both at the same level but not within the same instance
1107 -- then the body of the generic will be in the earlier instance.
1110 D1
: constant Int
:= Instantiation_Depth
(Sloc
(Ent
));
1111 D2
: constant Int
:= Instantiation_Depth
(Sloc
(N
));
1118 and then Is_Generic_Instance
(Scope
(Ent
))
1119 and then not In_Open_Scopes
(Scope
(Ent
))
1125 -- Now we can proceed, if the entity being called has a completion,
1126 -- then we are definitely OK, since we have already seen the body.
1128 if Has_Completion
(Ent
) then
1132 -- If there is no body, then nothing to do
1134 if not Has_Generic_Body
(N
) then
1138 -- Here we definitely have a bad instantiation
1141 ("?cannot instantiate& before body seen", N
, Ent
);
1143 if Present
(Instance_Spec
(N
)) then
1144 Supply_Bodies
(Instance_Spec
(N
));
1148 ("\?Program_Error will be raised at run time", N
);
1149 Insert_Elab_Check
(N
);
1150 Set_ABE_Is_Certain
(N
);
1151 end Check_Bad_Instantiation
;
1153 ---------------------
1154 -- Check_Elab_Call --
1155 ---------------------
1157 procedure Check_Elab_Call
1159 Outer_Scope
: Entity_Id
:= Empty
;
1160 In_Init_Proc
: Boolean := False)
1165 -- Start of processing for Check_Elab_Call
1168 -- If the call does not come from the main unit, there is nothing to
1169 -- check. Elaboration call from units in the context of the main unit
1170 -- will lead to semantic dependencies when those units are compiled.
1172 if not In_Extended_Main_Code_Unit
(N
) then
1176 -- For an entry call, check relevant restriction
1178 if Nkind
(N
) = N_Entry_Call_Statement
1179 and then not In_Subprogram_Or_Concurrent_Unit
1181 Check_Restriction
(No_Entry_Calls_In_Elaboration_Code
, N
);
1183 -- Nothing to do if this is not a call or attribute reference (happens
1184 -- in some error conditions, and in some cases where rewriting occurs).
1186 elsif Nkind
(N
) not in N_Subprogram_Call
1187 and then Nkind
(N
) /= N_Attribute_Reference
1191 -- Nothing to do if this is a call already rewritten for elab checking
1193 elsif Nkind
(Parent
(N
)) = N_Conditional_Expression
then
1196 -- Nothing to do if inside a generic template
1198 elsif Inside_A_Generic
1199 and then No
(Enclosing_Generic_Body
(N
))
1204 -- Here we have a call at elaboration time which must be checked
1206 if Debug_Flag_LL
then
1207 Write_Str
(" Check_Elab_Call: ");
1210 or else not Is_Entity_Name
(Name
(N
))
1212 Write_Str
("<<not entity name>> ");
1214 Write_Name
(Chars
(Entity
(Name
(N
))));
1217 Write_Str
(" call at ");
1218 Write_Location
(Sloc
(N
));
1222 -- Climb up the tree to make sure we are not inside default expression
1223 -- of a parameter specification or a record component, since in both
1224 -- these cases, we will be doing the actual call later, not now, and it
1225 -- is at the time of the actual call (statically speaking) that we must
1226 -- do our static check, not at the time of its initial analysis).
1228 -- However, we have to check calls within component definitions (e.g.
1229 -- a function call that determines an array component bound), so we
1230 -- terminate the loop in that case.
1233 while Present
(P
) loop
1234 if Nkind_In
(P
, N_Parameter_Specification
,
1235 N_Component_Declaration
)
1239 -- The call occurs within the constraint of a component,
1240 -- so it must be checked.
1242 elsif Nkind
(P
) = N_Component_Definition
then
1250 -- Stuff that happens only at the outer level
1252 if No
(Outer_Scope
) then
1253 Elab_Visited
.Set_Last
(0);
1255 -- Nothing to do if current scope is Standard (this is a bit odd, but
1256 -- it happens in the case of generic instantiations).
1258 C_Scope
:= Current_Scope
;
1260 if C_Scope
= Standard_Standard
then
1264 -- First case, we are in elaboration code
1266 From_Elab_Code
:= not In_Subprogram_Or_Concurrent_Unit
;
1267 if From_Elab_Code
then
1269 -- Complain if call that comes from source in preelaborated unit
1270 -- and we are not inside a subprogram (i.e. we are in elab code).
1272 if Comes_From_Source
(N
)
1273 and then In_Preelaborated_Unit
1274 and then not In_Inlined_Body
1275 and then Nkind
(N
) /= N_Attribute_Reference
1277 -- This is a warning in GNAT mode allowing such calls to be
1278 -- used in the predefined library with appropriate care.
1280 Error_Msg_Warn
:= GNAT_Mode
;
1282 ("<non-static call not allowed in preelaborated unit", N
);
1286 -- Second case, we are inside a subprogram or concurrent unit, which
1287 -- means we are not in elaboration code.
1290 -- In this case, the issue is whether we are inside the
1291 -- declarative part of the unit in which we live, or inside its
1292 -- statements. In the latter case, there is no issue of ABE calls
1293 -- at this level (a call from outside to the unit in which we live
1294 -- might cause an ABE, but that will be detected when we analyze
1295 -- that outer level call, as it recurses into the called unit).
1297 -- Climb up the tree, doing this test, and also testing for being
1298 -- inside a default expression, which, as discussed above, is not
1299 -- checked at this stage.
1308 -- If we find a parentless subtree, it seems safe to assume
1309 -- that we are not in a declarative part and that no
1310 -- checking is required.
1316 if Is_List_Member
(P
) then
1317 L
:= List_Containing
(P
);
1324 exit when Nkind
(P
) = N_Subunit
;
1326 -- Filter out case of default expressions, where we do not
1327 -- do the check at this stage.
1329 if Nkind
(P
) = N_Parameter_Specification
1331 Nkind
(P
) = N_Component_Declaration
1336 -- A protected body has no elaboration code and contains
1337 -- only other bodies.
1339 if Nkind
(P
) = N_Protected_Body
then
1342 elsif Nkind
(P
) = N_Subprogram_Body
1344 Nkind
(P
) = N_Task_Body
1346 Nkind
(P
) = N_Block_Statement
1348 Nkind
(P
) = N_Entry_Body
1350 if L
= Declarations
(P
) then
1353 -- We are not in elaboration code, but we are doing
1354 -- dynamic elaboration checks, in this case, we still
1355 -- need to do the call, since the subprogram we are in
1356 -- could be called from another unit, also in dynamic
1357 -- elaboration check mode, at elaboration time.
1359 elsif Dynamic_Elaboration_Checks
then
1361 -- We provide a debug flag to disable this check. That
1362 -- way we have an easy work around for regressions
1363 -- that are caused by this new check. This debug flag
1364 -- can be removed later.
1366 if Debug_Flag_DD
then
1370 -- Do the check in this case
1374 elsif Nkind
(P
) = N_Task_Body
then
1376 -- The check is deferred until Check_Task_Activation
1377 -- but we need to capture local suppress pragmas
1378 -- that may inhibit checks on this call.
1380 Ent
:= Get_Referenced_Ent
(N
);
1385 elsif Elaboration_Checks_Suppressed
(Current_Scope
)
1386 or else Elaboration_Checks_Suppressed
(Ent
)
1387 or else Elaboration_Checks_Suppressed
(Scope
(Ent
))
1389 Set_No_Elaboration_Check
(N
);
1394 -- Static model, call is not in elaboration code, we
1395 -- never need to worry, because in the static model the
1396 -- top level caller always takes care of things.
1407 Ent
:= Get_Referenced_Ent
(N
);
1413 -- Nothing to do if this is a recursive call (i.e. a call to
1414 -- an entity that is already in the Elab_Call stack)
1416 for J
in 1 .. Elab_Visited
.Last
loop
1417 if Ent
= Elab_Visited
.Table
(J
) then
1422 -- See if we need to analyze this call. We analyze it if either of
1423 -- the following conditions is met:
1425 -- It is an inner level call (since in this case it was triggered
1426 -- by an outer level call from elaboration code), but only if the
1427 -- call is within the scope of the original outer level call.
1429 -- It is an outer level call from elaboration code, or the called
1430 -- entity is in the same elaboration scope.
1432 -- And in these cases, we will check both inter-unit calls and
1433 -- intra-unit (within a single unit) calls.
1435 C_Scope
:= Current_Scope
;
1437 -- If not outer level call, then we follow it if it is within the
1438 -- original scope of the outer call.
1440 if Present
(Outer_Scope
)
1441 and then Within
(Scope
(Ent
), Outer_Scope
)
1447 Outer_Scope
=> Outer_Scope
,
1448 Inter_Unit_Only
=> False,
1449 In_Init_Proc
=> In_Init_Proc
);
1451 elsif Elaboration_Checks_Suppressed
(Current_Scope
) then
1454 elsif From_Elab_Code
then
1456 Check_A_Call
(N
, Ent
, Standard_Standard
, Inter_Unit_Only
=> False);
1458 elsif Same_Elaboration_Scope
(C_Scope
, Scope
(Ent
)) then
1460 Check_A_Call
(N
, Ent
, Scope
(Ent
), Inter_Unit_Only
=> False);
1462 -- If none of those cases holds, but Dynamic_Elaboration_Checks mode
1463 -- is set, then we will do the check, but only in the inter-unit case
1464 -- (this is to accommodate unguarded elaboration calls from other units
1465 -- in which this same mode is set). We don't want warnings in this case,
1466 -- it would generate warnings having nothing to do with elaboration.
1468 elsif Dynamic_Elaboration_Checks
then
1474 Inter_Unit_Only
=> True,
1475 Generate_Warnings
=> False);
1477 -- Otherwise nothing to do
1483 -- A call to an Init_Proc in elaboration code may bring additional
1484 -- dependencies, if some of the record components thereof have
1485 -- initializations that are function calls that come from source. We
1486 -- treat the current node as a call to each of these functions, to check
1487 -- their elaboration impact.
1489 if Is_Init_Proc
(Ent
)
1490 and then From_Elab_Code
1492 Process_Init_Proc
: declare
1493 Unit_Decl
: constant Node_Id
:= Unit_Declaration_Node
(Ent
);
1495 function Check_Init_Call
(Nod
: Node_Id
) return Traverse_Result
;
1496 -- Find subprogram calls within body of Init_Proc for Traverse
1497 -- instantiation below.
1499 procedure Traverse_Body
is new Traverse_Proc
(Check_Init_Call
);
1500 -- Traversal procedure to find all calls with body of Init_Proc
1502 ---------------------
1503 -- Check_Init_Call --
1504 ---------------------
1506 function Check_Init_Call
(Nod
: Node_Id
) return Traverse_Result
is
1510 if Nkind
(Nod
) in N_Subprogram_Call
1511 and then Is_Entity_Name
(Name
(Nod
))
1513 Func
:= Entity
(Name
(Nod
));
1515 if Comes_From_Source
(Func
) then
1517 (N
, Func
, Standard_Standard
, Inter_Unit_Only
=> True);
1525 end Check_Init_Call
;
1527 -- Start of processing for Process_Init_Proc
1530 if Nkind
(Unit_Decl
) = N_Subprogram_Body
then
1531 Traverse_Body
(Handled_Statement_Sequence
(Unit_Decl
));
1533 end Process_Init_Proc
;
1535 end Check_Elab_Call
;
1537 -----------------------
1538 -- Check_Elab_Assign --
1539 -----------------------
1541 procedure Check_Elab_Assign
(N
: Node_Id
) is
1545 Pkg_Spec
: Entity_Id
;
1546 Pkg_Body
: Entity_Id
;
1549 -- For record or array component, check prefix. If it is an access type,
1550 -- then there is nothing to do (we do not know what is being assigned),
1551 -- but otherwise this is an assignment to the prefix.
1553 if Nkind
(N
) = N_Indexed_Component
1555 Nkind
(N
) = N_Selected_Component
1559 if not Is_Access_Type
(Etype
(Prefix
(N
))) then
1560 Check_Elab_Assign
(Prefix
(N
));
1566 -- For type conversion, check expression
1568 if Nkind
(N
) = N_Type_Conversion
then
1569 Check_Elab_Assign
(Expression
(N
));
1573 -- Nothing to do if this is not an entity reference otherwise get entity
1575 if Is_Entity_Name
(N
) then
1581 -- What we are looking for is a reference in the body of a package that
1582 -- modifies a variable declared in the visible part of the package spec.
1585 and then Comes_From_Source
(N
)
1586 and then not Suppress_Elaboration_Warnings
(Ent
)
1587 and then Ekind
(Ent
) = E_Variable
1588 and then not In_Private_Part
(Ent
)
1589 and then Is_Library_Level_Entity
(Ent
)
1591 Scop
:= Current_Scope
;
1593 if No
(Scop
) or else Scop
= Standard_Standard
then
1595 elsif Ekind
(Scop
) = E_Package
1596 and then Is_Compilation_Unit
(Scop
)
1600 Scop
:= Scope
(Scop
);
1604 -- Here Scop points to the containing library package
1607 Pkg_Body
:= Body_Entity
(Pkg_Spec
);
1609 -- All OK if the package has an Elaborate_Body pragma
1611 if Has_Pragma_Elaborate_Body
(Scop
) then
1615 -- OK if entity being modified is not in containing package spec
1617 if not In_Same_Source_Unit
(Scop
, Ent
) then
1621 -- All OK if entity appears in generic package or generic instance.
1622 -- We just get too messed up trying to give proper warnings in the
1623 -- presence of generics. Better no message than a junk one.
1625 Scop
:= Scope
(Ent
);
1626 while Present
(Scop
) and then Scop
/= Pkg_Spec
loop
1627 if Ekind
(Scop
) = E_Generic_Package
then
1629 elsif Ekind
(Scop
) = E_Package
1630 and then Is_Generic_Instance
(Scop
)
1635 Scop
:= Scope
(Scop
);
1638 -- All OK if in task, don't issue warnings there
1640 if In_Task_Activation
then
1644 -- OK if no package body
1646 if No
(Pkg_Body
) then
1650 -- OK if reference is not in package body
1652 if not In_Same_Source_Unit
(Pkg_Body
, N
) then
1656 -- OK if package body has no handled statement sequence
1659 HSS
: constant Node_Id
:=
1660 Handled_Statement_Sequence
(Declaration_Node
(Pkg_Body
));
1662 if No
(HSS
) or else not Comes_From_Source
(HSS
) then
1667 -- We definitely have a case of a modification of an entity in
1668 -- the package spec from the elaboration code of the package body.
1669 -- We may not give the warning (because there are some additional
1670 -- checks to avoid too many false positives), but it would be a good
1671 -- idea for the binder to try to keep the body elaboration close to
1672 -- the spec elaboration.
1674 Set_Elaborate_Body_Desirable
(Pkg_Spec
);
1676 -- All OK in gnat mode (we know what we are doing)
1682 -- All OK if all warnings suppressed
1684 if Warning_Mode
= Suppress
then
1688 -- All OK if elaboration checks suppressed for entity
1690 if Checks_May_Be_Suppressed
(Ent
)
1691 and then Is_Check_Suppressed
(Ent
, Elaboration_Check
)
1696 -- OK if the entity is initialized. Note that the No_Initialization
1697 -- flag usually means that the initialization has been rewritten into
1698 -- assignments, but that still counts for us.
1701 Decl
: constant Node_Id
:= Declaration_Node
(Ent
);
1703 if Nkind
(Decl
) = N_Object_Declaration
1704 and then (Present
(Expression
(Decl
))
1705 or else No_Initialization
(Decl
))
1711 -- Here is where we give the warning
1713 -- All OK if warnings suppressed on the entity
1715 if not Has_Warnings_Off
(Ent
) then
1716 Error_Msg_Sloc
:= Sloc
(Ent
);
1719 ("?elaboration code may access& before it is initialized",
1722 ("\?suggest adding pragma Elaborate_Body to spec of &",
1725 ("\?or an explicit initialization could be added #", N
);
1728 if not All_Errors_Mode
then
1729 Set_Suppress_Elaboration_Warnings
(Ent
);
1732 end Check_Elab_Assign
;
1734 ----------------------
1735 -- Check_Elab_Calls --
1736 ----------------------
1738 procedure Check_Elab_Calls
is
1740 -- If expansion is disabled, do not generate any checks. Also skip
1741 -- checks if any subunits are missing because in either case we lack the
1742 -- full information that we need, and no object file will be created in
1745 if not Expander_Active
1746 or else Is_Generic_Unit
(Cunit_Entity
(Main_Unit
))
1747 or else Subunits_Missing
1752 -- Skip delayed calls if we had any errors
1754 if Serious_Errors_Detected
= 0 then
1755 Delaying_Elab_Checks
:= False;
1756 Expander_Mode_Save_And_Set
(True);
1758 for J
in Delay_Check
.First
.. Delay_Check
.Last
loop
1759 Push_Scope
(Delay_Check
.Table
(J
).Curscop
);
1760 From_Elab_Code
:= Delay_Check
.Table
(J
).From_Elab_Code
;
1762 Check_Internal_Call_Continue
(
1763 N
=> Delay_Check
.Table
(J
).N
,
1764 E
=> Delay_Check
.Table
(J
).E
,
1765 Outer_Scope
=> Delay_Check
.Table
(J
).Outer_Scope
,
1766 Orig_Ent
=> Delay_Check
.Table
(J
).Orig_Ent
);
1771 -- Set Delaying_Elab_Checks back on for next main compilation
1773 Expander_Mode_Restore
;
1774 Delaying_Elab_Checks
:= True;
1776 end Check_Elab_Calls
;
1778 ------------------------------
1779 -- Check_Elab_Instantiation --
1780 ------------------------------
1782 procedure Check_Elab_Instantiation
1784 Outer_Scope
: Entity_Id
:= Empty
)
1789 -- Check for and deal with bad instantiation case. There is some
1790 -- duplicated code here, but we will worry about this later ???
1792 Check_Bad_Instantiation
(N
);
1794 if ABE_Is_Certain
(N
) then
1798 -- Nothing to do if we do not have an instantiation (happens in some
1799 -- error cases, and also in the formal package declaration case)
1801 if Nkind
(N
) not in N_Generic_Instantiation
then
1805 -- Nothing to do if inside a generic template
1807 if Inside_A_Generic
then
1811 -- Nothing to do if the instantiation is not in the main unit
1813 if not In_Extended_Main_Code_Unit
(N
) then
1817 Ent
:= Get_Generic_Entity
(N
);
1818 From_Elab_Code
:= not In_Subprogram_Or_Concurrent_Unit
;
1820 -- See if we need to analyze this instantiation. We analyze it if
1821 -- either of the following conditions is met:
1823 -- It is an inner level instantiation (since in this case it was
1824 -- triggered by an outer level call from elaboration code), but
1825 -- only if the instantiation is within the scope of the original
1826 -- outer level call.
1828 -- It is an outer level instantiation from elaboration code, or the
1829 -- instantiated entity is in the same elaboration scope.
1831 -- And in these cases, we will check both the inter-unit case and
1832 -- the intra-unit (within a single unit) case.
1834 C_Scope
:= Current_Scope
;
1836 if Present
(Outer_Scope
)
1837 and then Within
(Scope
(Ent
), Outer_Scope
)
1840 Check_A_Call
(N
, Ent
, Outer_Scope
, Inter_Unit_Only
=> False);
1842 elsif From_Elab_Code
then
1844 Check_A_Call
(N
, Ent
, Standard_Standard
, Inter_Unit_Only
=> False);
1846 elsif Same_Elaboration_Scope
(C_Scope
, Scope
(Ent
)) then
1848 Check_A_Call
(N
, Ent
, Scope
(Ent
), Inter_Unit_Only
=> False);
1850 -- If none of those cases holds, but Dynamic_Elaboration_Checks mode is
1851 -- set, then we will do the check, but only in the inter-unit case (this
1852 -- is to accommodate unguarded elaboration calls from other units in
1853 -- which this same mode is set). We inhibit warnings in this case, since
1854 -- this instantiation is not occurring in elaboration code.
1856 elsif Dynamic_Elaboration_Checks
then
1862 Inter_Unit_Only
=> True,
1863 Generate_Warnings
=> False);
1868 end Check_Elab_Instantiation
;
1870 -------------------------
1871 -- Check_Internal_Call --
1872 -------------------------
1874 procedure Check_Internal_Call
1877 Outer_Scope
: Entity_Id
;
1878 Orig_Ent
: Entity_Id
)
1880 Inst_Case
: constant Boolean := Nkind
(N
) in N_Generic_Instantiation
;
1883 -- If not function or procedure call or instantiation, then ignore
1884 -- call (this happens in some error case and rewriting cases)
1886 if Nkind
(N
) /= N_Function_Call
1888 Nkind
(N
) /= N_Procedure_Call_Statement
1894 -- Nothing to do if this is a call or instantiation that has
1895 -- already been found to be a sure ABE
1897 elsif ABE_Is_Certain
(N
) then
1900 -- Nothing to do if errors already detected (avoid cascaded errors)
1902 elsif Serious_Errors_Detected
/= 0 then
1905 -- Nothing to do if not in full analysis mode
1907 elsif not Full_Analysis
then
1910 -- Nothing to do if analyzing in special spec-expression mode, since the
1911 -- call is not actually being made at this time.
1913 elsif In_Spec_Expression
then
1916 -- Nothing to do for call to intrinsic subprogram
1918 elsif Is_Intrinsic_Subprogram
(E
) then
1921 -- No need to trace local calls if checking task activation, because
1922 -- other local bodies are elaborated already.
1924 elsif In_Task_Activation
then
1927 -- Nothing to do if call is within a generic unit
1929 elsif Inside_A_Generic
then
1933 -- Delay this call if we are still delaying calls
1935 if Delaying_Elab_Checks
then
1936 Delay_Check
.Append
(
1939 Orig_Ent
=> Orig_Ent
,
1940 Curscop
=> Current_Scope
,
1941 Outer_Scope
=> Outer_Scope
,
1942 From_Elab_Code
=> From_Elab_Code
));
1945 -- Otherwise, call phase 2 continuation right now
1948 Check_Internal_Call_Continue
(N
, E
, Outer_Scope
, Orig_Ent
);
1950 end Check_Internal_Call
;
1952 ----------------------------------
1953 -- Check_Internal_Call_Continue --
1954 ----------------------------------
1956 procedure Check_Internal_Call_Continue
1959 Outer_Scope
: Entity_Id
;
1960 Orig_Ent
: Entity_Id
)
1962 Loc
: constant Source_Ptr
:= Sloc
(N
);
1963 Inst_Case
: constant Boolean := Is_Generic_Unit
(E
);
1968 function Find_Elab_Reference
(N
: Node_Id
) return Traverse_Result
;
1969 -- Function applied to each node as we traverse the body. Checks for
1970 -- call or entity reference that needs checking, and if so checks it.
1971 -- Always returns OK, so entire tree is traversed, except that as
1972 -- described below subprogram bodies are skipped for now.
1974 procedure Traverse
is new Atree
.Traverse_Proc
(Find_Elab_Reference
);
1975 -- Traverse procedure using above Find_Elab_Reference function
1977 -------------------------
1978 -- Find_Elab_Reference --
1979 -------------------------
1981 function Find_Elab_Reference
(N
: Node_Id
) return Traverse_Result
is
1985 -- If user has specified that there are no entry calls in elaboration
1986 -- code, do not trace past an accept statement, because the rendez-
1987 -- vous will happen after elaboration.
1989 if (Nkind
(Original_Node
(N
)) = N_Accept_Statement
1990 or else Nkind
(Original_Node
(N
)) = N_Selective_Accept
)
1991 and then Restriction_Active
(No_Entry_Calls_In_Elaboration_Code
)
1995 -- If we have a function call, check it
1997 elsif Nkind
(N
) = N_Function_Call
then
1998 Check_Elab_Call
(N
, Outer_Scope
);
2001 -- If we have a procedure call, check the call, and also check
2002 -- arguments that are assignments (OUT or IN OUT mode formals).
2004 elsif Nkind
(N
) = N_Procedure_Call_Statement
then
2005 Check_Elab_Call
(N
, Outer_Scope
, In_Init_Proc
=> Is_Init_Proc
(E
));
2007 Actual
:= First_Actual
(N
);
2008 while Present
(Actual
) loop
2009 if Known_To_Be_Assigned
(Actual
) then
2010 Check_Elab_Assign
(Actual
);
2013 Next_Actual
(Actual
);
2018 -- If we have an access attribute for a subprogram, check
2019 -- it. Suppress this behavior under debug flag.
2021 elsif not Debug_Flag_Dot_UU
2022 and then Nkind
(N
) = N_Attribute_Reference
2023 and then (Attribute_Name
(N
) = Name_Access
2025 Attribute_Name
(N
) = Name_Unrestricted_Access
)
2026 and then Is_Entity_Name
(Prefix
(N
))
2027 and then Is_Subprogram
(Entity
(Prefix
(N
)))
2029 Check_Elab_Call
(N
, Outer_Scope
);
2032 -- If we have a generic instantiation, check it
2034 elsif Nkind
(N
) in N_Generic_Instantiation
then
2035 Check_Elab_Instantiation
(N
, Outer_Scope
);
2038 -- Skip subprogram bodies that come from source (wait for call to
2039 -- analyze these). The reason for the come from source test is to
2040 -- avoid catching task bodies.
2042 -- For task bodies, we should really avoid these too, waiting for the
2043 -- task activation, but that's too much trouble to catch for now, so
2044 -- we go in unconditionally. This is not so terrible, it means the
2045 -- error backtrace is not quite complete, and we are too eager to
2046 -- scan bodies of tasks that are unused, but this is hardly very
2049 elsif Nkind
(N
) = N_Subprogram_Body
2050 and then Comes_From_Source
(N
)
2054 elsif Nkind
(N
) = N_Assignment_Statement
2055 and then Comes_From_Source
(N
)
2057 Check_Elab_Assign
(Name
(N
));
2063 end Find_Elab_Reference
;
2065 -- Start of processing for Check_Internal_Call_Continue
2068 -- Save outer level call if at outer level
2070 if Elab_Call
.Last
= 0 then
2071 Outer_Level_Sloc
:= Loc
;
2074 Elab_Visited
.Append
(E
);
2076 -- If the call is to a function that renames a literal, no check
2079 if Ekind
(E
) = E_Enumeration_Literal
then
2083 Sbody
:= Unit_Declaration_Node
(E
);
2085 if Nkind
(Sbody
) /= N_Subprogram_Body
2087 Nkind
(Sbody
) /= N_Package_Body
2089 Ebody
:= Corresponding_Body
(Sbody
);
2094 Sbody
:= Unit_Declaration_Node
(Ebody
);
2098 -- If the body appears after the outer level call or instantiation then
2099 -- we have an error case handled below.
2101 if Earlier_In_Extended_Unit
(Outer_Level_Sloc
, Sloc
(Sbody
))
2102 and then not In_Task_Activation
2106 -- If we have the instantiation case we are done, since we now
2107 -- know that the body of the generic appeared earlier.
2109 elsif Inst_Case
then
2112 -- Otherwise we have a call, so we trace through the called body to see
2113 -- if it has any problems.
2116 pragma Assert
(Nkind
(Sbody
) = N_Subprogram_Body
);
2118 Elab_Call
.Append
((Cloc
=> Loc
, Ent
=> E
));
2120 if Debug_Flag_LL
then
2121 Write_Str
("Elab_Call.Last = ");
2122 Write_Int
(Int
(Elab_Call
.Last
));
2123 Write_Str
(" Ent = ");
2124 Write_Name
(Chars
(E
));
2126 Write_Location
(Sloc
(N
));
2130 -- Now traverse declarations and statements of subprogram body. Note
2131 -- that we cannot simply Traverse (Sbody), since traverse does not
2132 -- normally visit subprogram bodies.
2137 Decl
:= First
(Declarations
(Sbody
));
2138 while Present
(Decl
) loop
2144 Traverse
(Handled_Statement_Sequence
(Sbody
));
2146 Elab_Call
.Decrement_Last
;
2150 -- Here is the case of calling a subprogram where the body has not yet
2151 -- been encountered. A warning message is needed, except if this is the
2152 -- case of appearing within an aspect specification that results in
2153 -- a check call, we do not really have such a situation, so no warning
2154 -- is needed (e.g. the case of a precondition, where the call appears
2155 -- textually before the body, but in actual fact is moved to the
2156 -- appropriate subprogram body and so does not need a check).
2163 if Nkind
(P
) in N_Subexpr
then
2165 elsif Nkind
(P
) = N_If_Statement
2166 and then Nkind
(Original_Node
(P
)) = N_Pragma
2167 and then Present
(Corresponding_Aspect
(Original_Node
(P
)))
2176 -- Not that special case, warning and dynamic check is required
2178 -- If we have nothing in the call stack, then this is at the outer
2179 -- level, and the ABE is bound to occur.
2181 if Elab_Call
.Last
= 0 then
2184 ("?cannot instantiate& before body seen", N
, Orig_Ent
);
2187 ("?cannot call& before body seen", N
, Orig_Ent
);
2191 ("\?Program_Error will be raised at run time", N
);
2192 Insert_Elab_Check
(N
);
2194 -- Call is not at outer level
2197 -- Deal with dynamic elaboration check
2199 if not Elaboration_Checks_Suppressed
(E
) then
2200 Set_Elaboration_Entity_Required
(E
);
2202 -- Case of no elaboration entity allocated yet
2204 if No
(Elaboration_Entity
(E
)) then
2206 -- Create object declaration for elaboration entity, and put it
2207 -- just in front of the spec of the subprogram or generic unit,
2208 -- in the same scope as this unit.
2211 Loce
: constant Source_Ptr
:= Sloc
(E
);
2212 Ent
: constant Entity_Id
:=
2213 Make_Defining_Identifier
(Loc
,
2214 Chars
=> New_External_Name
(Chars
(E
), 'E'));
2217 Set_Elaboration_Entity
(E
, Ent
);
2218 Push_Scope
(Scope
(E
));
2220 Insert_Action
(Declaration_Node
(E
),
2221 Make_Object_Declaration
(Loce
,
2222 Defining_Identifier
=> Ent
,
2223 Object_Definition
=>
2224 New_Occurrence_Of
(Standard_Short_Integer
, Loce
),
2226 Make_Integer_Literal
(Loc
, Uint_0
)));
2228 -- Set elaboration flag at the point of the body
2230 Set_Elaboration_Flag
(Sbody
, E
);
2232 -- Kill current value indication. This is necessary because
2233 -- the tests of this flag are inserted out of sequence and
2234 -- must not pick up bogus indications of the wrong constant
2235 -- value. Also, this is never a true constant, since one way
2236 -- or another, it gets reset.
2238 Set_Current_Value
(Ent
, Empty
);
2239 Set_Last_Assignment
(Ent
, Empty
);
2240 Set_Is_True_Constant
(Ent
, False);
2245 -- Generate check of the elaboration counter
2247 Insert_Elab_Check
(N
,
2248 Make_Attribute_Reference
(Loc
,
2249 Attribute_Name
=> Name_Elaborated
,
2250 Prefix
=> New_Occurrence_Of
(E
, Loc
)));
2253 -- Generate the warning
2255 if not Suppress_Elaboration_Warnings
(E
)
2256 and then not Elaboration_Checks_Suppressed
(E
)
2260 ("instantiation of& may occur before body is seen?",
2264 ("call to& may occur before body is seen?", N
, Orig_Ent
);
2268 ("\Program_Error may be raised at run time?", N
);
2274 -- Set flag to suppress further warnings on same subprogram
2275 -- unless in all errors mode
2277 if not All_Errors_Mode
then
2278 Set_Suppress_Elaboration_Warnings
(E
);
2280 end Check_Internal_Call_Continue
;
2282 ---------------------------
2283 -- Check_Task_Activation --
2284 ---------------------------
2286 procedure Check_Task_Activation
(N
: Node_Id
) is
2287 Loc
: constant Source_Ptr
:= Sloc
(N
);
2288 Inter_Procs
: constant Elist_Id
:= New_Elmt_List
;
2289 Intra_Procs
: constant Elist_Id
:= New_Elmt_List
;
2292 Task_Scope
: Entity_Id
;
2293 Cunit_SC
: Boolean := False;
2296 Enclosing
: Entity_Id
;
2298 procedure Add_Task_Proc
(Typ
: Entity_Id
);
2299 -- Add to Task_Procs the task body procedure(s) of task types in Typ.
2300 -- For record types, this procedure recurses over component types.
2302 procedure Collect_Tasks
(Decls
: List_Id
);
2303 -- Collect the types of the tasks that are to be activated in the given
2304 -- list of declarations, in order to perform elaboration checks on the
2305 -- corresponding task procedures which are called implicitly here.
2307 function Outer_Unit
(E
: Entity_Id
) return Entity_Id
;
2308 -- find enclosing compilation unit of Entity, ignoring subunits, or
2309 -- else enclosing subprogram. If E is not a package, there is no need
2310 -- for inter-unit elaboration checks.
2316 procedure Add_Task_Proc
(Typ
: Entity_Id
) is
2318 Proc
: Entity_Id
:= Empty
;
2321 if Is_Task_Type
(Typ
) then
2322 Proc
:= Get_Task_Body_Procedure
(Typ
);
2324 elsif Is_Array_Type
(Typ
)
2325 and then Has_Task
(Base_Type
(Typ
))
2327 Add_Task_Proc
(Component_Type
(Typ
));
2329 elsif Is_Record_Type
(Typ
)
2330 and then Has_Task
(Base_Type
(Typ
))
2332 Comp
:= First_Component
(Typ
);
2333 while Present
(Comp
) loop
2334 Add_Task_Proc
(Etype
(Comp
));
2335 Comp
:= Next_Component
(Comp
);
2339 -- If the task type is another unit, we will perform the usual
2340 -- elaboration check on its enclosing unit. If the type is in the
2341 -- same unit, we can trace the task body as for an internal call,
2342 -- but we only need to examine other external calls, because at
2343 -- the point the task is activated, internal subprogram bodies
2344 -- will have been elaborated already. We keep separate lists for
2345 -- each kind of task.
2347 -- Skip this test if errors have occurred, since in this case
2348 -- we can get false indications.
2350 if Serious_Errors_Detected
/= 0 then
2354 if Present
(Proc
) then
2355 if Outer_Unit
(Scope
(Proc
)) = Enclosing
then
2357 if No
(Corresponding_Body
(Unit_Declaration_Node
(Proc
)))
2359 (not Is_Generic_Instance
(Scope
(Proc
))
2361 Scope
(Proc
) = Scope
(Defining_Identifier
(Decl
)))
2364 ("task will be activated before elaboration of its body?",
2367 ("\Program_Error will be raised at run time?", Decl
);
2370 Present
(Corresponding_Body
(Unit_Declaration_Node
(Proc
)))
2372 Append_Elmt
(Proc
, Intra_Procs
);
2376 -- No need for multiple entries of the same type
2378 Elmt
:= First_Elmt
(Inter_Procs
);
2379 while Present
(Elmt
) loop
2380 if Node
(Elmt
) = Proc
then
2387 Append_Elmt
(Proc
, Inter_Procs
);
2396 procedure Collect_Tasks
(Decls
: List_Id
) is
2398 if Present
(Decls
) then
2399 Decl
:= First
(Decls
);
2400 while Present
(Decl
) loop
2401 if Nkind
(Decl
) = N_Object_Declaration
2402 and then Has_Task
(Etype
(Defining_Identifier
(Decl
)))
2404 Add_Task_Proc
(Etype
(Defining_Identifier
(Decl
)));
2416 function Outer_Unit
(E
: Entity_Id
) return Entity_Id
is
2421 while Present
(Outer
) loop
2422 if Elaboration_Checks_Suppressed
(Outer
) then
2426 exit when Is_Child_Unit
(Outer
)
2427 or else Scope
(Outer
) = Standard_Standard
2428 or else Ekind
(Outer
) /= E_Package
;
2429 Outer
:= Scope
(Outer
);
2435 -- Start of processing for Check_Task_Activation
2438 Enclosing
:= Outer_Unit
(Current_Scope
);
2440 -- Find all tasks declared in the current unit
2442 if Nkind
(N
) = N_Package_Body
then
2443 P
:= Unit_Declaration_Node
(Corresponding_Spec
(N
));
2445 Collect_Tasks
(Declarations
(N
));
2446 Collect_Tasks
(Visible_Declarations
(Specification
(P
)));
2447 Collect_Tasks
(Private_Declarations
(Specification
(P
)));
2449 elsif Nkind
(N
) = N_Package_Declaration
then
2450 Collect_Tasks
(Visible_Declarations
(Specification
(N
)));
2451 Collect_Tasks
(Private_Declarations
(Specification
(N
)));
2454 Collect_Tasks
(Declarations
(N
));
2457 -- We only perform detailed checks in all tasks are library level
2458 -- entities. If the master is a subprogram or task, activation will
2459 -- depend on the activation of the master itself.
2461 -- Should dynamic checks be added in the more general case???
2463 if Ekind
(Enclosing
) /= E_Package
then
2467 -- For task types defined in other units, we want the unit containing
2468 -- the task body to be elaborated before the current one.
2470 Elmt
:= First_Elmt
(Inter_Procs
);
2471 while Present
(Elmt
) loop
2473 Task_Scope
:= Outer_Unit
(Scope
(Ent
));
2475 if not Is_Compilation_Unit
(Task_Scope
) then
2478 elsif Suppress_Elaboration_Warnings
(Task_Scope
)
2479 or else Elaboration_Checks_Suppressed
(Task_Scope
)
2483 elsif Dynamic_Elaboration_Checks
then
2484 if not Elaboration_Checks_Suppressed
(Ent
)
2485 and then not Cunit_SC
2487 not Restriction_Active
(No_Entry_Calls_In_Elaboration_Code
)
2489 -- Runtime elaboration check required. Generate check of the
2490 -- elaboration counter for the unit containing the entity.
2492 Insert_Elab_Check
(N
,
2493 Make_Attribute_Reference
(Loc
,
2494 Attribute_Name
=> Name_Elaborated
,
2496 New_Occurrence_Of
(Spec_Entity
(Task_Scope
), Loc
)));
2500 -- Force the binder to elaborate other unit first
2502 if not Suppress_Elaboration_Warnings
(Ent
)
2503 and then not Elaboration_Checks_Suppressed
(Ent
)
2504 and then Elab_Warnings
2505 and then not Suppress_Elaboration_Warnings
(Task_Scope
)
2506 and then not Elaboration_Checks_Suppressed
(Task_Scope
)
2508 Error_Msg_Node_2
:= Task_Scope
;
2510 ("activation of an instance of task type&" &
2511 " requires pragma Elaborate_All on &?", N
, Ent
);
2514 Activate_Elaborate_All_Desirable
(N
, Task_Scope
);
2515 Set_Suppress_Elaboration_Warnings
(Task_Scope
);
2521 -- For tasks declared in the current unit, trace other calls within
2522 -- the task procedure bodies, which are available.
2524 In_Task_Activation
:= True;
2526 Elmt
:= First_Elmt
(Intra_Procs
);
2527 while Present
(Elmt
) loop
2529 Check_Internal_Call_Continue
(N
, Ent
, Enclosing
, Ent
);
2533 In_Task_Activation
:= False;
2534 end Check_Task_Activation
;
2536 --------------------------------
2537 -- Set_Elaboration_Constraint --
2538 --------------------------------
2540 procedure Set_Elaboration_Constraint
2545 Elab_Unit
: Entity_Id
;
2546 Init_Call
: constant Boolean :=
2547 Chars
(Subp
) = Name_Initialize
2548 and then Comes_From_Source
(Subp
)
2549 and then Present
(Parameter_Associations
(Call
))
2550 and then Is_Controlled
(Etype
(First_Actual
(Call
)));
2552 -- If the unit is mentioned in a with_clause of the current unit, it is
2553 -- visible, and we can set the elaboration flag.
2555 if Is_Immediately_Visible
(Scop
)
2556 or else (Is_Child_Unit
(Scop
) and then Is_Visible_Child_Unit
(Scop
))
2558 Activate_Elaborate_All_Desirable
(Call
, Scop
);
2559 Set_Suppress_Elaboration_Warnings
(Scop
, True);
2563 -- If this is not an initialization call or a call using object notation
2564 -- we know that the unit of the called entity is in the context, and
2565 -- we can set the flag as well. The unit need not be visible if the call
2566 -- occurs within an instantiation.
2568 if Is_Init_Proc
(Subp
)
2570 or else Nkind
(Original_Node
(Call
)) = N_Selected_Component
2572 null; -- detailed processing follows.
2575 Activate_Elaborate_All_Desirable
(Call
, Scop
);
2576 Set_Suppress_Elaboration_Warnings
(Scop
, True);
2580 -- If the unit is not in the context, there must be an intermediate unit
2581 -- that is, on which we need to place to elaboration flag. This happens
2582 -- with init proc calls.
2584 if Is_Init_Proc
(Subp
)
2587 -- The initialization call is on an object whose type is not declared
2588 -- in the same scope as the subprogram. The type of the object must
2589 -- be a subtype of the type of operation. This object is the first
2590 -- actual in the call.
2593 Typ
: constant Entity_Id
:=
2594 Etype
(First
(Parameter_Associations
(Call
)));
2596 Elab_Unit
:= Scope
(Typ
);
2597 while (Present
(Elab_Unit
))
2598 and then not Is_Compilation_Unit
(Elab_Unit
)
2600 Elab_Unit
:= Scope
(Elab_Unit
);
2604 -- If original node uses selected component notation, the prefix is
2605 -- visible and determines the scope that must be elaborated. After
2606 -- rewriting, the prefix is the first actual in the call.
2608 elsif Nkind
(Original_Node
(Call
)) = N_Selected_Component
then
2609 Elab_Unit
:= Scope
(Etype
(First
(Parameter_Associations
(Call
))));
2611 -- Not one of special cases above
2614 -- Using previously computed scope. If the elaboration check is
2615 -- done after analysis, the scope is not visible any longer, but
2616 -- must still be in the context.
2621 Activate_Elaborate_All_Desirable
(Call
, Elab_Unit
);
2622 Set_Suppress_Elaboration_Warnings
(Elab_Unit
, True);
2623 end Set_Elaboration_Constraint
;
2625 ------------------------
2626 -- Get_Referenced_Ent --
2627 ------------------------
2629 function Get_Referenced_Ent
(N
: Node_Id
) return Entity_Id
is
2633 if Nkind
(N
) = N_Attribute_Reference
then
2641 elsif Nkind
(Nam
) = N_Selected_Component
then
2642 return Entity
(Selector_Name
(Nam
));
2643 elsif not Is_Entity_Name
(Nam
) then
2646 return Entity
(Nam
);
2648 end Get_Referenced_Ent
;
2650 ----------------------
2651 -- Has_Generic_Body --
2652 ----------------------
2654 function Has_Generic_Body
(N
: Node_Id
) return Boolean is
2655 Ent
: constant Entity_Id
:= Get_Generic_Entity
(N
);
2656 Decl
: constant Node_Id
:= Unit_Declaration_Node
(Ent
);
2659 function Find_Body_In
(E
: Entity_Id
; N
: Node_Id
) return Node_Id
;
2660 -- Determine if the list of nodes headed by N and linked by Next
2661 -- contains a package body for the package spec entity E, and if so
2662 -- return the package body. If not, then returns Empty.
2664 function Load_Package_Body
(Nam
: Unit_Name_Type
) return Node_Id
;
2665 -- This procedure is called load the unit whose name is given by Nam.
2666 -- This unit is being loaded to see whether it contains an optional
2667 -- generic body. The returned value is the loaded unit, which is always
2668 -- a package body (only package bodies can contain other entities in the
2669 -- sense in which Has_Generic_Body is interested). We only attempt to
2670 -- load bodies if we are generating code. If we are in semantics check
2671 -- only mode, then it would be wrong to load bodies that are not
2672 -- required from a semantic point of view, so in this case we return
2673 -- Empty. The result is that the caller may incorrectly decide that a
2674 -- generic spec does not have a body when in fact it does, but the only
2675 -- harm in this is that some warnings on elaboration problems may be
2676 -- lost in semantic checks only mode, which is not big loss. We also
2677 -- return Empty if we go for a body and it is not there.
2679 function Locate_Corresponding_Body
(PE
: Entity_Id
) return Node_Id
;
2680 -- PE is the entity for a package spec. This function locates the
2681 -- corresponding package body, returning Empty if none is found. The
2682 -- package body returned is fully parsed but may not yet be analyzed,
2683 -- so only syntactic fields should be referenced.
2689 function Find_Body_In
(E
: Entity_Id
; N
: Node_Id
) return Node_Id
is
2694 while Present
(Nod
) loop
2696 -- If we found the package body we are looking for, return it
2698 if Nkind
(Nod
) = N_Package_Body
2699 and then Chars
(Defining_Unit_Name
(Nod
)) = Chars
(E
)
2703 -- If we found the stub for the body, go after the subunit,
2704 -- loading it if necessary.
2706 elsif Nkind
(Nod
) = N_Package_Body_Stub
2707 and then Chars
(Defining_Identifier
(Nod
)) = Chars
(E
)
2709 if Present
(Library_Unit
(Nod
)) then
2710 return Unit
(Library_Unit
(Nod
));
2713 return Load_Package_Body
(Get_Unit_Name
(Nod
));
2716 -- If neither package body nor stub, keep looking on chain
2726 -----------------------
2727 -- Load_Package_Body --
2728 -----------------------
2730 function Load_Package_Body
(Nam
: Unit_Name_Type
) return Node_Id
is
2731 U
: Unit_Number_Type
;
2734 if Operating_Mode
/= Generate_Code
then
2747 return Unit
(Cunit
(U
));
2750 end Load_Package_Body
;
2752 -------------------------------
2753 -- Locate_Corresponding_Body --
2754 -------------------------------
2756 function Locate_Corresponding_Body
(PE
: Entity_Id
) return Node_Id
is
2757 Spec
: constant Node_Id
:= Declaration_Node
(PE
);
2758 Decl
: constant Node_Id
:= Parent
(Spec
);
2759 Scop
: constant Entity_Id
:= Scope
(PE
);
2763 if Is_Library_Level_Entity
(PE
) then
2765 -- If package is a library unit that requires a body, we have no
2766 -- choice but to go after that body because it might contain an
2767 -- optional body for the original generic package.
2769 if Unit_Requires_Body
(PE
) then
2771 -- Load the body. Note that we are a little careful here to use
2772 -- Spec to get the unit number, rather than PE or Decl, since
2773 -- in the case where the package is itself a library level
2774 -- instantiation, Spec will properly reference the generic
2775 -- template, which is what we really want.
2779 (Get_Body_Name
(Unit_Name
(Get_Source_Unit
(Spec
))));
2781 -- But if the package is a library unit that does NOT require
2782 -- a body, then no body is permitted, so we are sure that there
2783 -- is no body for the original generic package.
2789 -- Otherwise look and see if we are embedded in a further package
2791 elsif Is_Package_Or_Generic_Package
(Scop
) then
2793 -- If so, get the body of the enclosing package, and look in
2794 -- its package body for the package body we are looking for.
2796 PBody
:= Locate_Corresponding_Body
(Scop
);
2801 return Find_Body_In
(PE
, First
(Declarations
(PBody
)));
2804 -- If we are not embedded in a further package, then the body
2805 -- must be in the same declarative part as we are.
2808 return Find_Body_In
(PE
, Next
(Decl
));
2810 end Locate_Corresponding_Body
;
2812 -- Start of processing for Has_Generic_Body
2815 if Present
(Corresponding_Body
(Decl
)) then
2818 elsif Unit_Requires_Body
(Ent
) then
2821 -- Compilation units cannot have optional bodies
2823 elsif Is_Compilation_Unit
(Ent
) then
2826 -- Otherwise look at what scope we are in
2829 Scop
:= Scope
(Ent
);
2831 -- Case of entity is in other than a package spec, in this case
2832 -- the body, if present, must be in the same declarative part.
2834 if not Is_Package_Or_Generic_Package
(Scop
) then
2839 -- Declaration node may get us a spec, so if so, go to
2840 -- the parent declaration.
2842 P
:= Declaration_Node
(Ent
);
2843 while not Is_List_Member
(P
) loop
2847 return Present
(Find_Body_In
(Ent
, Next
(P
)));
2850 -- If the entity is in a package spec, then we have to locate
2851 -- the corresponding package body, and look there.
2855 PBody
: constant Node_Id
:= Locate_Corresponding_Body
(Scop
);
2863 (Find_Body_In
(Ent
, (First
(Declarations
(PBody
)))));
2868 end Has_Generic_Body
;
2870 -----------------------
2871 -- Insert_Elab_Check --
2872 -----------------------
2874 procedure Insert_Elab_Check
(N
: Node_Id
; C
: Node_Id
:= Empty
) is
2876 Loc
: constant Source_Ptr
:= Sloc
(N
);
2879 -- If expansion is disabled, do not generate any checks. Also
2880 -- skip checks if any subunits are missing because in either
2881 -- case we lack the full information that we need, and no object
2882 -- file will be created in any case.
2884 if not Expander_Active
or else Subunits_Missing
then
2888 -- If we have a generic instantiation, where Instance_Spec is set,
2889 -- then this field points to a generic instance spec that has
2890 -- been inserted before the instantiation node itself, so that
2891 -- is where we want to insert a check.
2893 if Nkind
(N
) in N_Generic_Instantiation
2894 and then Present
(Instance_Spec
(N
))
2896 Nod
:= Instance_Spec
(N
);
2901 -- If we are inserting at the top level, insert in Aux_Decls
2903 if Nkind
(Parent
(Nod
)) = N_Compilation_Unit
then
2905 ADN
: constant Node_Id
:= Aux_Decls_Node
(Parent
(Nod
));
2911 Make_Raise_Program_Error
(Loc
,
2912 Reason
=> PE_Access_Before_Elaboration
);
2915 Make_Raise_Program_Error
(Loc
,
2916 Condition
=> Make_Op_Not
(Loc
, C
),
2917 Reason
=> PE_Access_Before_Elaboration
);
2920 if No
(Declarations
(ADN
)) then
2921 Set_Declarations
(ADN
, New_List
(R
));
2923 Append_To
(Declarations
(ADN
), R
);
2929 -- Otherwise just insert before the node in question. However, if
2930 -- the context of the call has already been analyzed, an insertion
2931 -- will not work if it depends on subsequent expansion (e.g. a call in
2932 -- a branch of a short-circuit). In that case we replace the call with
2933 -- a conditional expression, or with a Raise if it is unconditional.
2934 -- Unfortunately this does not work if the call has a dynamic size,
2935 -- because gigi regards it as a dynamic-sized temporary. If such a call
2936 -- appears in a short-circuit expression, the elaboration check will be
2937 -- missed (rare enough ???). Otherwise, the code below inserts the check
2938 -- at the appropriate place before the call. Same applies in the even
2939 -- rarer case the return type has a known size but is unconstrained.
2942 if Nkind
(N
) = N_Function_Call
2943 and then Analyzed
(Parent
(N
))
2944 and then Size_Known_At_Compile_Time
(Etype
(N
))
2946 (not Has_Discriminants
(Etype
(N
))
2947 or else Is_Constrained
(Etype
(N
)))
2951 Typ
: constant Entity_Id
:= Etype
(N
);
2952 Chk
: constant Boolean := Do_Range_Check
(N
);
2954 R
: constant Node_Id
:=
2955 Make_Raise_Program_Error
(Loc
,
2956 Reason
=> PE_Access_Before_Elaboration
);
2967 Reloc_N
:= Relocate_Node
(N
);
2968 Save_Interps
(N
, Reloc_N
);
2970 Make_Conditional_Expression
(Loc
,
2971 Expressions
=> New_List
(C
, Reloc_N
, R
)));
2974 Analyze_And_Resolve
(N
, Typ
);
2976 -- If the original call requires a range check, so does the
2977 -- conditional expression.
2980 Enable_Range_Check
(N
);
2982 Set_Do_Range_Check
(N
, False);
2989 Make_Raise_Program_Error
(Loc
,
2990 Reason
=> PE_Access_Before_Elaboration
));
2993 Make_Raise_Program_Error
(Loc
,
2997 Reason
=> PE_Access_Before_Elaboration
));
3001 end Insert_Elab_Check
;
3003 -------------------------------
3004 -- Is_Finalization_Procedure --
3005 -------------------------------
3007 function Is_Finalization_Procedure
(Id
: Entity_Id
) return Boolean is
3009 -- Check whether Id is a procedure with at least one parameter
3011 if Ekind
(Id
) = E_Procedure
3012 and then Present
(First_Formal
(Id
))
3015 Typ
: constant Entity_Id
:= Etype
(First_Formal
(Id
));
3016 Deep_Fin
: Entity_Id
:= Empty
;
3017 Fin
: Entity_Id
:= Empty
;
3020 -- If the type of the first formal does not require finalization
3021 -- actions, then this is definitely not [Deep_]Finalize.
3023 if not Needs_Finalization
(Typ
) then
3027 -- At this point we have the following scenario:
3029 -- procedure Name (Param1 : [in] [out] Ctrl[; Param2 : ...]);
3031 -- Recover the two possible versions of [Deep_]Finalize using the
3032 -- type of the first parameter and compare with the input.
3034 Deep_Fin
:= TSS
(Typ
, TSS_Deep_Finalize
);
3036 if Is_Controlled
(Typ
) then
3037 Fin
:= Find_Prim_Op
(Typ
, Name_Finalize
);
3041 (Present
(Deep_Fin
) and then Id
= Deep_Fin
)
3043 (Present
(Fin
) and then Id
= Fin
);
3048 end Is_Finalization_Procedure
;
3054 procedure Output_Calls
(N
: Node_Id
) is
3057 function Is_Printable_Error_Name
(Nm
: Name_Id
) return Boolean;
3058 -- An internal function, used to determine if a name, Nm, is either
3059 -- a non-internal name, or is an internal name that is printable
3060 -- by the error message circuits (i.e. it has a single upper
3061 -- case letter at the end).
3063 function Is_Printable_Error_Name
(Nm
: Name_Id
) return Boolean is
3065 if not Is_Internal_Name
(Nm
) then
3068 elsif Name_Len
= 1 then
3072 Name_Len
:= Name_Len
- 1;
3073 return not Is_Internal_Name
;
3075 end Is_Printable_Error_Name
;
3077 -- Start of processing for Output_Calls
3080 for J
in reverse 1 .. Elab_Call
.Last
loop
3081 Error_Msg_Sloc
:= Elab_Call
.Table
(J
).Cloc
;
3083 Ent
:= Elab_Call
.Table
(J
).Ent
;
3085 if Is_Generic_Unit
(Ent
) then
3086 Error_Msg_NE
("\?& instantiated #", N
, Ent
);
3088 elsif Is_Init_Proc
(Ent
) then
3089 Error_Msg_N
("\?initialization procedure called #", N
);
3091 elsif Is_Printable_Error_Name
(Chars
(Ent
)) then
3092 Error_Msg_NE
("\?& called #", N
, Ent
);
3095 Error_Msg_N
("\? called #", N
);
3100 ----------------------------
3101 -- Same_Elaboration_Scope --
3102 ----------------------------
3104 function Same_Elaboration_Scope
(Scop1
, Scop2
: Entity_Id
) return Boolean is
3109 -- Find elaboration scope for Scop1
3110 -- This is either a subprogram or a compilation unit.
3113 while S1
/= Standard_Standard
3114 and then not Is_Compilation_Unit
(S1
)
3115 and then (Ekind
(S1
) = E_Package
3117 Ekind
(S1
) = E_Protected_Type
3119 Ekind
(S1
) = E_Block
)
3124 -- Find elaboration scope for Scop2
3127 while S2
/= Standard_Standard
3128 and then not Is_Compilation_Unit
(S2
)
3129 and then (Ekind
(S2
) = E_Package
3131 Ekind
(S2
) = E_Protected_Type
3133 Ekind
(S2
) = E_Block
)
3139 end Same_Elaboration_Scope
;
3145 procedure Set_C_Scope
is
3147 while not Is_Compilation_Unit
(C_Scope
) loop
3148 C_Scope
:= Scope
(C_Scope
);
3156 function Spec_Entity
(E
: Entity_Id
) return Entity_Id
is
3160 -- Check for case of body entity
3161 -- Why is the check for E_Void needed???
3163 if Ekind_In
(E
, E_Void
, E_Subprogram_Body
, E_Package_Body
) then
3167 Decl
:= Parent
(Decl
);
3168 exit when Nkind
(Decl
) in N_Proper_Body
;
3171 return Corresponding_Spec
(Decl
);
3182 procedure Supply_Bodies
(N
: Node_Id
) is
3184 if Nkind
(N
) = N_Subprogram_Declaration
then
3186 Ent
: constant Entity_Id
:= Defining_Unit_Name
(Specification
(N
));
3189 -- Internal subprograms will already have a generated body, so
3190 -- there is no need to provide a stub for them.
3192 if No
(Corresponding_Body
(N
)) then
3194 Loc
: constant Source_Ptr
:= Sloc
(N
);
3196 Formals
: constant List_Id
:= Copy_Parameter_List
(Ent
);
3197 Nam
: constant Entity_Id
:=
3198 Make_Defining_Identifier
(Loc
, Chars
(Ent
));
3200 Stats
: constant List_Id
:=
3202 (Make_Raise_Program_Error
(Loc
,
3203 Reason
=> PE_Access_Before_Elaboration
));
3206 if Ekind
(Ent
) = E_Function
then
3208 Make_Function_Specification
(Loc
,
3209 Defining_Unit_Name
=> Nam
,
3210 Parameter_Specifications
=> Formals
,
3211 Result_Definition
=>
3213 (Result_Definition
(Specification
(N
))));
3215 -- We cannot reliably make a return statement for this
3216 -- body, but none is needed because the call raises
3219 Set_Return_Present
(Ent
);
3223 Make_Procedure_Specification
(Loc
,
3224 Defining_Unit_Name
=> Nam
,
3225 Parameter_Specifications
=> Formals
);
3228 B
:= Make_Subprogram_Body
(Loc
,
3229 Specification
=> Spec
,
3230 Declarations
=> New_List
,
3231 Handled_Statement_Sequence
=>
3232 Make_Handled_Sequence_Of_Statements
(Loc
, Stats
));
3233 Insert_After
(N
, B
);
3239 elsif Nkind
(N
) = N_Package_Declaration
then
3241 Spec
: constant Node_Id
:= Specification
(N
);
3243 Push_Scope
(Defining_Unit_Name
(Spec
));
3244 Supply_Bodies
(Visible_Declarations
(Spec
));
3245 Supply_Bodies
(Private_Declarations
(Spec
));
3251 procedure Supply_Bodies
(L
: List_Id
) is
3256 while Present
(Elmt
) loop
3257 Supply_Bodies
(Elmt
);
3267 function Within
(E1
, E2
: Entity_Id
) return Boolean is
3274 elsif Scop
= Standard_Standard
then
3277 Scop
:= Scope
(Scop
);
3282 --------------------------
3283 -- Within_Elaborate_All --
3284 --------------------------
3286 function Within_Elaborate_All
3287 (Unit
: Unit_Number_Type
;
3288 E
: Entity_Id
) return Boolean
3290 type Unit_Number_Set
is array (Main_Unit
.. Last_Unit
) of Boolean;
3291 pragma Pack
(Unit_Number_Set
);
3293 Seen
: Unit_Number_Set
:= (others => False);
3294 -- Seen (X) is True after we have seen unit X in the walk. This is used
3295 -- to prevent processing the same unit more than once.
3297 Result
: Boolean := False;
3299 procedure Helper
(Unit
: Unit_Number_Type
);
3300 -- This helper procedure does all the work for Within_Elaborate_All. It
3301 -- walks the dependency graph, and sets Result to True if it finds an
3302 -- appropriate Elaborate_All.
3308 procedure Helper
(Unit
: Unit_Number_Type
) is
3309 CU
: constant Node_Id
:= Cunit
(Unit
);
3313 Elab_Id
: Entity_Id
;
3320 Seen
(Unit
) := True;
3323 -- First, check for Elaborate_Alls on this unit
3325 Item
:= First
(Context_Items
(CU
));
3326 while Present
(Item
) loop
3327 if Nkind
(Item
) = N_Pragma
3328 and then Pragma_Name
(Item
) = Name_Elaborate_All
3330 -- Return if some previous error on the pragma itself
3332 if Error_Posted
(Item
) then
3338 (Expression
(First
(Pragma_Argument_Associations
(Item
))));
3345 Par
:= Parent
(Unit_Declaration_Node
(Elab_Id
));
3347 Item2
:= First
(Context_Items
(Par
));
3348 while Present
(Item2
) loop
3349 if Nkind
(Item2
) = N_With_Clause
3350 and then Entity
(Name
(Item2
)) = E
3351 and then not Limited_Present
(Item2
)
3364 -- Second, recurse on with's. We could do this as part of the above
3365 -- loop, but it's probably more efficient to have two loops, because
3366 -- the relevant Elaborate_All is likely to be on the initial unit. In
3367 -- other words, we're walking the with's breadth-first. This part is
3368 -- only necessary in the dynamic elaboration model.
3370 if Dynamic_Elaboration_Checks
then
3371 Item
:= First
(Context_Items
(CU
));
3372 while Present
(Item
) loop
3373 if Nkind
(Item
) = N_With_Clause
3374 and then not Limited_Present
(Item
)
3376 -- Note: the following call to Get_Cunit_Unit_Number does a
3377 -- linear search, which could be slow, but it's OK because
3378 -- we're about to give a warning anyway. Also, there might
3379 -- be hundreds of units, but not millions. If it turns out
3380 -- to be a problem, we could store the Get_Cunit_Unit_Number
3381 -- in each N_Compilation_Unit node, but that would involve
3382 -- rearranging N_Compilation_Unit_Aux to make room.
3384 Helper
(Get_Cunit_Unit_Number
(Library_Unit
(Item
)));
3396 -- Start of processing for Within_Elaborate_All
3401 end Within_Elaborate_All
;