1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, 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 -- Package containing utility procedures used throughout the semantics
28 with Einfo; use Einfo;
29 with Exp_Tss; use Exp_Tss;
30 with Namet; use Namet;
31 with Nmake; use Nmake;
32 with Snames; use Snames;
33 with Types; use Types;
34 with Uintp; use Uintp;
35 with Urealp; use Urealp;
39 function Abstract_Interface_List (Typ : Entity_Id) return List_Id;
40 -- Given a type that implements interfaces look for its associated
41 -- definition node and return its list of interfaces.
43 procedure Add_Access_Type_To_Process (E : Entity_Id; A : Entity_Id);
44 -- Add A to the list of access types to process when expanding the
47 procedure Add_Global_Declaration (N : Node_Id);
48 -- These procedures adds a declaration N at the library level, to be
49 -- elaborated before any other code in the unit. It is used for example
50 -- for the entity that marks whether a unit has been elaborated. The
51 -- declaration is added to the Declarations list of the Aux_Decls_Node
52 -- for the current unit. The declarations are added in the current scope,
53 -- so the caller should push a new scope as required before the call.
55 function Addressable (V : Uint) return Boolean;
56 function Addressable (V : Int) return Boolean;
57 pragma Inline (Addressable);
58 -- Returns True if the value of V is the word size of an addressable
59 -- factor of the word size (typically 8, 16, 32 or 64).
61 function Alignment_In_Bits (E : Entity_Id) return Uint;
62 -- If the alignment of the type or object E is currently known to the
63 -- compiler, then this function returns the alignment value in bits.
64 -- Otherwise Uint_0 is returned, indicating that the alignment of the
65 -- entity is not yet known to the compiler.
67 procedure Apply_Compile_Time_Constraint_Error
70 Reason : RT_Exception_Code;
71 Ent : Entity_Id := Empty;
72 Typ : Entity_Id := Empty;
73 Loc : Source_Ptr := No_Location;
74 Rep : Boolean := True;
75 Warn : Boolean := False);
76 -- N is a subexpression which will raise constraint error when evaluated
77 -- at runtime. Msg is a message that explains the reason for raising the
78 -- exception. The last character is ? if the message is always a warning,
79 -- even in Ada 95, and is not a ? if the message represents an illegality
80 -- (because of violation of static expression rules) in Ada 95 (but not
81 -- in Ada 83). Typically this routine posts all messages at the Sloc of
82 -- node N. However, if Loc /= No_Location, Loc is the Sloc used to output
83 -- the message. After posting the appropriate message, and if the flag
84 -- Rep is set, this routine replaces the expression with an appropriate
85 -- N_Raise_Constraint_Error node using the given Reason code. This node
86 -- is then marked as being static if the original node is static, but
87 -- sets the flag Raises_Constraint_Error, preventing further evaluation.
88 -- The error message may contain a } or & insertion character. This
89 -- normally references Etype (N), unless the Ent argument is given
90 -- explicitly, in which case it is used instead. The type of the raise
91 -- node that is built is normally Etype (N), but if the Typ parameter
92 -- is present, this is used instead. Warn is normally False. If it is
93 -- True then the message is treated as a warning even though it does
94 -- not end with a ? (this is used when the caller wants to parameterize
95 -- whether an error or warning is given.
97 procedure Bad_Predicated_Subtype_Use
101 -- This is called when Typ, a predicated subtype, is used in a context
102 -- which does not allow the use of a predicated subtype. Msg is passed
103 -- to Error_Msg_FE to output an appropriate message using N as the
104 -- location, and Typ as the entity. The caller must set up any insertions
105 -- other than the & for the type itself. Note that if Typ is a generic
106 -- actual type, then the message will be output as a warning, and a
107 -- raise Program_Error is inserted using Insert_Action with node N as
108 -- the insertion point. Node N also supplies the source location for
109 -- construction of the raise node. If Typ is NOT a type with predicates
110 -- this call has no effect.
112 function Build_Actual_Subtype
114 N : Node_Or_Entity_Id) return Node_Id;
115 -- Build an anonymous subtype for an entity or expression, using the
116 -- bounds of the entity or the discriminants of the enclosing record.
117 -- T is the type for which the actual subtype is required, and N is either
118 -- a defining identifier, or any subexpression.
120 function Build_Actual_Subtype_Of_Component
122 N : Node_Id) return Node_Id;
123 -- Determine whether a selected component has a type that depends on
124 -- discriminants, and build actual subtype for it if so.
126 function Build_Default_Subtype
128 N : Node_Id) return Entity_Id;
129 -- If T is an unconstrained type with defaulted discriminants, build a
130 -- subtype constrained by the default values, insert the subtype
131 -- declaration in the tree before N, and return the entity of that
132 -- subtype. Otherwise, simply return T.
134 function Build_Discriminal_Subtype_Of_Component
135 (T : Entity_Id) return Node_Id;
136 -- Determine whether a record component has a type that depends on
137 -- discriminants, and build actual subtype for it if so.
139 procedure Build_Elaboration_Entity (N : Node_Id; Spec_Id : Entity_Id);
140 -- Given a compilation unit node N, allocate an elaboration counter for
141 -- the compilation unit, and install it in the Elaboration_Entity field
142 -- of Spec_Id, the entity for the compilation unit.
144 function Cannot_Raise_Constraint_Error (Expr : Node_Id) return Boolean;
145 -- Returns True if the expression cannot possibly raise Constraint_Error.
146 -- The response is conservative in the sense that a result of False does
147 -- not necessarily mean that CE could be raised, but a response of True
148 -- means that for sure CE cannot be raised.
150 procedure Check_Implicit_Dereference (Nam : Node_Id; Typ : Entity_Id);
151 -- AI05-139-2: Accessors and iterators for containers. This procedure
152 -- checks whether T is a reference type, and if so it adds an interprettion
153 -- to Expr whose type is the designated type of the reference_discriminant.
155 procedure Check_Later_Vs_Basic_Declarations
157 During_Parsing : Boolean);
158 -- If During_Parsing is True, check for misplacement of later vs basic
159 -- declarations in Ada 83. If During_Parsing is False, and the SPARK
160 -- restriction is set, do the same: although SPARK 95 removes the
161 -- distinction between initial and later declarative items, the distinction
162 -- remains in the Examiner (JB01-005). Note that the Examiner does not
163 -- count package declarations in later declarative items.
165 procedure Check_Dynamically_Tagged_Expression
168 Related_Nod : Node_Id);
169 -- Check wrong use of dynamically tagged expression
171 procedure Check_Fully_Declared (T : Entity_Id; N : Node_Id);
172 -- Verify that the full declaration of type T has been seen. If not, place
173 -- error message on node N. Used in object declarations, type conversions
174 -- and qualified expressions.
176 procedure Check_Nested_Access (Ent : Entity_Id);
177 -- Check whether Ent denotes an entity declared in an uplevel scope, which
178 -- is accessed inside a nested procedure, and set Has_Up_Level_Access flag
179 -- accordingly. This is currently only enabled for VM_Target /= No_VM.
181 procedure Check_Order_Dependence;
182 -- Examine the actuals in a top-level call to determine whether aliasing
183 -- between two actuals, one of which is writable, can make the call
186 procedure Check_Potentially_Blocking_Operation (N : Node_Id);
187 -- N is one of the statement forms that is a potentially blocking
188 -- operation. If it appears within a protected action, emit warning.
190 procedure Check_Unprotected_Access
193 -- Check whether the expression is a pointer to a protected component,
194 -- and the context is external to the protected operation, to warn against
195 -- a possible unlocked access to data.
197 procedure Check_VMS (Construct : Node_Id);
198 -- Check that this the target is OpenVMS, and if so, return with no effect,
199 -- otherwise post an error noting this can only be used with OpenVMS ports.
200 -- The argument is the construct in question and is used to post the error
203 procedure Collect_Interfaces
205 Ifaces_List : out Elist_Id;
206 Exclude_Parents : Boolean := False;
207 Use_Full_View : Boolean := True);
208 -- Ada 2005 (AI-251): Collect whole list of abstract interfaces that are
209 -- directly or indirectly implemented by T. Exclude_Parents is used to
210 -- avoid the addition of inherited interfaces to the generated list.
211 -- Use_Full_View is used to collect the interfaces using the full-view
214 procedure Collect_Interface_Components
215 (Tagged_Type : Entity_Id;
216 Components_List : out Elist_Id);
217 -- Ada 2005 (AI-251): Collect all the tag components associated with the
218 -- secondary dispatch tables of a tagged type.
220 procedure Collect_Interfaces_Info
222 Ifaces_List : out Elist_Id;
223 Components_List : out Elist_Id;
224 Tags_List : out Elist_Id);
225 -- Ada 2005 (AI-251): Collect all the interfaces associated with T plus
226 -- the record component and tag associated with each of these interfaces.
227 -- On exit Ifaces_List, Components_List and Tags_List have the same number
228 -- of elements, and elements at the same position on these tables provide
229 -- information on the same interface type.
231 procedure Collect_Parents
234 Use_Full_View : Boolean := True);
235 -- Collect all the parents of Typ. Use_Full_View is used to collect them
236 -- using the full-view of private parents (if available).
238 function Collect_Primitive_Operations (T : Entity_Id) return Elist_Id;
239 -- Called upon type derivation and extension. We scan the declarative part
240 -- in which the type appears, and collect subprograms that have one
241 -- subsidiary subtype of the type. These subprograms can only appear after
244 function Compile_Time_Constraint_Error
247 Ent : Entity_Id := Empty;
248 Loc : Source_Ptr := No_Location;
249 Warn : Boolean := False) return Node_Id;
250 -- This is similar to Apply_Compile_Time_Constraint_Error in that it
251 -- generates a warning (or error) message in the same manner, but it does
252 -- not replace any nodes. For convenience, the function always returns its
253 -- first argument. The message is a warning if the message ends with ?, or
254 -- we are operating in Ada 83 mode, or the Warn parameter is set to True.
256 procedure Conditional_Delay (New_Ent, Old_Ent : Entity_Id);
257 -- Sets the Has_Delayed_Freeze flag of New if the Delayed_Freeze flag of
258 -- Old is set and Old has no yet been Frozen (i.e. Is_Frozen is false).
260 function Copy_Parameter_List (Subp_Id : Entity_Id) return List_Id;
261 -- Utility to create a parameter profile for a new subprogram spec, when
262 -- the subprogram has a body that acts as spec. This is done for some cases
263 -- of inlining, and for private protected ops. Also used to create bodies
264 -- for stubbed subprograms.
266 function Current_Entity (N : Node_Id) return Entity_Id;
267 pragma Inline (Current_Entity);
268 -- Find the currently visible definition for a given identifier, that is to
269 -- say the first entry in the visibility chain for the Chars of N.
271 function Current_Entity_In_Scope (N : Node_Id) return Entity_Id;
272 -- Find whether there is a previous definition for identifier N in the
273 -- current scope. Because declarations for a scope are not necessarily
274 -- contiguous (e.g. for packages) the first entry on the visibility chain
275 -- for N is not necessarily in the current scope.
277 function Current_Scope return Entity_Id;
278 -- Get entity representing current scope
280 function Current_Subprogram return Entity_Id;
281 -- Returns current enclosing subprogram. If Current_Scope is a subprogram,
282 -- then that is what is returned, otherwise the Enclosing_Subprogram of the
283 -- Current_Scope is returned. The returned value is Empty if this is called
284 -- from a library package which is not within any subprogram.
286 function Defining_Entity (N : Node_Id) return Entity_Id;
287 -- Given a declaration N, returns the associated defining entity. If the
288 -- declaration has a specification, the entity is obtained from the
289 -- specification. If the declaration has a defining unit name, then the
290 -- defining entity is obtained from the defining unit name ignoring any
291 -- child unit prefixes.
293 function Denotes_Discriminant
295 Check_Concurrent : Boolean := False) return Boolean;
296 -- Returns True if node N is an Entity_Name node for a discriminant. If the
297 -- flag Check_Concurrent is true, function also returns true when N denotes
298 -- the discriminal of the discriminant of a concurrent type. This is needed
299 -- to disable some optimizations on private components of protected types,
300 -- and constraint checks on entry families constrained by discriminants.
302 function Denotes_Same_Object (A1, A2 : Node_Id) return Boolean;
303 function Denotes_Same_Prefix (A1, A2 : Node_Id) return Boolean;
304 -- Functions to detect suspicious overlapping between actuals in a call,
305 -- when one of them is writable. The predicates are those proposed in
306 -- AI05-0144, to detect dangerous order dependence in complex calls.
307 -- I would add a parameter Warn which enables more extensive testing of
308 -- cases as we find appropriate when we are only warning ??? Or perhaps
309 -- return an indication of (Error, Warn, OK) ???
311 function Denotes_Variable (N : Node_Id) return Boolean;
312 -- Returns True if node N denotes a single variable without parentheses
314 function Depends_On_Discriminant (N : Node_Id) return Boolean;
315 -- Returns True if N denotes a discriminant or if N is a range, a subtype
316 -- indication or a scalar subtype where one of the bounds is a
319 function Designate_Same_Unit
321 Name2 : Node_Id) return Boolean;
322 -- Return true if Name1 and Name2 designate the same unit name; each of
323 -- these names is supposed to be a selected component name, an expanded
324 -- name, a defining program unit name or an identifier.
326 function Enclosing_CPP_Parent (Typ : Entity_Id) return Entity_Id;
327 -- Returns the closest ancestor of Typ that is a CPP type.
329 function Enclosing_Generic_Body
330 (N : Node_Id) return Node_Id;
331 -- Returns the Node_Id associated with the innermost enclosing generic
332 -- body, if any. If none, then returns Empty.
334 function Enclosing_Generic_Unit
335 (N : Node_Id) return Node_Id;
336 -- Returns the Node_Id associated with the innermost enclosing generic
337 -- unit, if any. If none, then returns Empty.
339 function Enclosing_Lib_Unit_Entity return Entity_Id;
340 -- Returns the entity of enclosing N_Compilation_Unit Node which is the
341 -- root of the current scope (which must not be Standard_Standard, and the
342 -- caller is responsible for ensuring this condition).
344 function Enclosing_Lib_Unit_Node (N : Node_Id) return Node_Id;
345 -- Returns the enclosing N_Compilation_Unit Node that is the root of a
346 -- subtree containing N.
348 function Enclosing_Package (E : Entity_Id) return Entity_Id;
349 -- Utility function to return the Ada entity of the package enclosing
350 -- the entity E, if any. Returns Empty if no enclosing package.
352 function Enclosing_Subprogram (E : Entity_Id) return Entity_Id;
353 -- Utility function to return the Ada entity of the subprogram enclosing
354 -- the entity E, if any. Returns Empty if no enclosing subprogram.
356 procedure Ensure_Freeze_Node (E : Entity_Id);
357 -- Make sure a freeze node is allocated for entity E. If necessary, build
358 -- and initialize a new freeze node and set Has_Delayed_Freeze True for E.
360 procedure Enter_Name (Def_Id : Entity_Id);
361 -- Insert new name in symbol table of current scope with check for
362 -- duplications (error message is issued if a conflict is found).
363 -- Note: Enter_Name is not used for overloadable entities, instead these
364 -- are entered using Sem_Ch6.Enter_Overloadable_Entity.
366 procedure Explain_Limited_Type (T : Entity_Id; N : Node_Id);
367 -- This procedure is called after issuing a message complaining about an
368 -- inappropriate use of limited type T. If useful, it adds additional
369 -- continuation lines to the message explaining why type T is limited.
370 -- Messages are placed at node N.
372 procedure Find_Actual
374 Formal : out Entity_Id;
376 -- Determines if the node N is an actual parameter of a function of a
377 -- procedure call. If so, then Formal points to the entity for the formal
378 -- (Ekind is E_In_Parameter, E_Out_Parameter, or E_In_Out_Parameter) and
379 -- Call is set to the node for the corresponding call. If the node N is not
380 -- an actual parameter then Formal and Call are set to Empty.
382 function Find_Corresponding_Discriminant
384 Typ : Entity_Id) return Entity_Id;
385 -- Because discriminants may have different names in a generic unit and in
386 -- an instance, they are resolved positionally when possible. A reference
387 -- to a discriminant carries the discriminant that it denotes when it is
388 -- analyzed. Subsequent uses of this id on a different type denotes the
389 -- discriminant at the same position in this new type.
391 procedure Find_Overlaid_Entity
395 -- The node N should be an address representation clause. Determines if
396 -- the target expression is the address of an entity with an optional
397 -- offset. If so, set Ent to the entity and, if there is an offset, set
398 -- Off to True, otherwise to False. If N is not an address representation
399 -- clause, or if it is not possible to determine that the address is of
400 -- this form, then set Ent to Empty.
402 function Find_Parameter_Type (Param : Node_Id) return Entity_Id;
403 -- Return the type of formal parameter Param as determined by its
406 function Find_Static_Alternative (N : Node_Id) return Node_Id;
407 -- N is a case statement whose expression is a compile-time value.
408 -- Determine the alternative chosen, so that the code of non-selected
409 -- alternatives, and the warnings that may apply to them, are removed.
411 function Find_Body_Discriminal
412 (Spec_Discriminant : Entity_Id) return Entity_Id;
413 -- Given a discriminant of the record type that implements a task or
414 -- protected type, return the discriminal of the corresponding discriminant
415 -- of the actual concurrent type.
417 function First_Actual (Node : Node_Id) return Node_Id;
418 -- Node is an N_Function_Call or N_Procedure_Call_Statement node. The
419 -- result returned is the first actual parameter in declaration order
420 -- (not the order of parameters as they appeared in the source, which
421 -- can be quite different as a result of the use of named parameters).
422 -- Empty is returned for a call with no parameters. The procedure for
423 -- iterating through the actuals in declaration order is to use this
424 -- function to find the first actual, and then use Next_Actual to obtain
425 -- the next actual in declaration order. Note that the value returned
426 -- is always the expression (not the N_Parameter_Association nodes,
427 -- even if named association is used).
429 procedure Gather_Components
432 Governed_By : List_Id;
434 Report_Errors : out Boolean);
435 -- The purpose of this procedure is to gather the valid components in a
436 -- record type according to the values of its discriminants, in order to
437 -- validate the components of a record aggregate.
439 -- Typ is the type of the aggregate when its constrained discriminants
440 -- need to be collected, otherwise it is Empty.
442 -- Comp_List is an N_Component_List node.
444 -- Governed_By is a list of N_Component_Association nodes, where each
445 -- choice list contains the name of a discriminant and the expression
446 -- field gives its value. The values of the discriminants governing
447 -- the (possibly nested) variant parts in Comp_List are found in this
448 -- Component_Association List.
450 -- Into is the list where the valid components are appended. Note that
451 -- Into need not be an Empty list. If it's not, components are attached
454 -- Report_Errors is set to True if the values of the discriminants are
457 -- This procedure is also used when building a record subtype. If the
458 -- discriminant constraint of the subtype is static, the components of the
459 -- subtype are only those of the variants selected by the values of the
460 -- discriminants. Otherwise all components of the parent must be included
461 -- in the subtype for semantic analysis.
463 function Get_Actual_Subtype (N : Node_Id) return Entity_Id;
464 -- Given a node for an expression, obtain the actual subtype of the
465 -- expression. In the case of a parameter where the formal is an
466 -- unconstrained array or discriminated type, this will be the previously
467 -- constructed subtype of the actual. Note that this is not quite the
468 -- "Actual Subtype" of the RM, since it is always a constrained type, i.e.
469 -- it is the subtype of the value of the actual. The actual subtype is also
470 -- returned in other cases where it has already been constructed for an
471 -- object. Otherwise the expression type is returned unchanged, except for
472 -- the case of an unconstrained array type, where an actual subtype is
473 -- created, using Insert_Actions if necessary to insert any associated
476 function Get_Actual_Subtype_If_Available (N : Node_Id) return Entity_Id;
477 -- This is like Get_Actual_Subtype, except that it never constructs an
478 -- actual subtype. If an actual subtype is already available, i.e. the
479 -- Actual_Subtype field of the corresponding entity is set, then it is
480 -- returned. Otherwise the Etype of the node is returned.
482 function Get_Body_From_Stub (N : Node_Id) return Node_Id;
483 -- Return the body node for a stub (subprogram or package)
485 function Get_Default_External_Name (E : Node_Or_Entity_Id) return Node_Id;
486 -- This is used to construct the string literal node representing a
487 -- default external name, i.e. one that is constructed from the name of an
488 -- entity, or (in the case of extended DEC import/export pragmas, an
489 -- identifier provided as the external name. Letters in the name are
490 -- according to the setting of Opt.External_Name_Default_Casing.
492 function Get_Enclosing_Object (N : Node_Id) return Entity_Id;
493 -- If expression N references a part of an object, return this object.
494 -- Otherwise return Empty. Expression N should have been resolved already.
496 function Get_Ensures_From_Test_Case_Pragma (N : Node_Id) return Node_Id;
497 -- Return the Ensures component of Test_Case pragma N, or Empty otherwise
499 function Get_Generic_Entity (N : Node_Id) return Entity_Id;
500 -- Returns the true generic entity in an instantiation. If the name in the
501 -- instantiation is a renaming, the function returns the renamed generic.
503 procedure Get_Index_Bounds (N : Node_Id; L, H : out Node_Id);
504 -- This procedure assigns to L and H respectively the values of the low and
505 -- high bounds of node N, which must be a range, subtype indication, or the
506 -- name of a scalar subtype. The result in L, H may be set to Error if
507 -- there was an earlier error in the range.
509 function Get_Enum_Lit_From_Pos
512 Loc : Source_Ptr) return Node_Id;
513 -- This function returns an identifier denoting the E_Enumeration_Literal
514 -- entity for the specified value from the enumeration type or subtype T.
515 -- The second argument is the Pos value, which is assumed to be in range.
516 -- The third argument supplies a source location for constructed nodes
517 -- returned by this function.
519 procedure Get_Library_Unit_Name_String (Decl_Node : Node_Id);
520 -- Retrieve the fully expanded name of the library unit declared by
521 -- Decl_Node into the name buffer.
523 function Get_Name_Entity_Id (Id : Name_Id) return Entity_Id;
524 pragma Inline (Get_Name_Entity_Id);
525 -- An entity value is associated with each name in the name table. The
526 -- Get_Name_Entity_Id function fetches the Entity_Id of this entity, which
527 -- is the innermost visible entity with the given name. See the body of
528 -- Sem_Ch8 for further details on handling of entity visibility.
530 function Get_Name_From_Test_Case_Pragma (N : Node_Id) return String_Id;
531 -- Return the Name component of Test_Case pragma N
533 function Get_Pragma_Id (N : Node_Id) return Pragma_Id;
534 pragma Inline (Get_Pragma_Id);
535 -- Obtains the Pragma_Id from the Chars field of Pragma_Identifier (N)
537 function Get_Referenced_Object (N : Node_Id) return Node_Id;
538 -- Given a node, return the renamed object if the node represents a renamed
539 -- object, otherwise return the node unchanged. The node may represent an
540 -- arbitrary expression.
542 function Get_Renamed_Entity (E : Entity_Id) return Entity_Id;
543 -- Given an entity for an exception, package, subprogram or generic unit,
544 -- returns the ultimately renamed entity if this is a renaming. If this is
545 -- not a renamed entity, returns its argument. It is an error to call this
546 -- with any other kind of entity.
548 function Get_Requires_From_Test_Case_Pragma (N : Node_Id) return Node_Id;
549 -- Return the Requires component of Test_Case pragma N, or Empty otherwise
551 function Get_Subprogram_Entity (Nod : Node_Id) return Entity_Id;
552 -- Nod is either a procedure call statement, or a function call, or an
553 -- accept statement node. This procedure finds the Entity_Id of the related
554 -- subprogram or entry and returns it, or if no subprogram can be found,
557 function Get_Subprogram_Body (E : Entity_Id) return Node_Id;
558 -- Given the entity for a subprogram (E_Function or E_Procedure), return
559 -- the corresponding N_Subprogram_Body node. If the corresponding body
560 -- is missing (as for an imported subprogram), return Empty.
562 function Get_Task_Body_Procedure (E : Entity_Id) return Node_Id;
563 pragma Inline (Get_Task_Body_Procedure);
564 -- Given an entity for a task type or subtype, retrieves the
565 -- Task_Body_Procedure field from the corresponding task type declaration.
567 function Has_Access_Values (T : Entity_Id) return Boolean;
568 -- Returns true if type or subtype T is an access type, or has a component
569 -- (at any recursive level) that is an access type. This is a conservative
570 -- predicate, if it is not known whether or not T contains access values
571 -- (happens for generic formals in some cases), then False is returned.
572 -- Note that tagged types return False. Even though the tag is implemented
573 -- as an access type internally, this function tests only for access types
574 -- known to the programmer. See also Has_Tagged_Component.
576 type Alignment_Result is (Known_Compatible, Unknown, Known_Incompatible);
577 -- Result of Has_Compatible_Alignment test, description found below. Note
578 -- that the values are arranged in increasing order of problematicness.
580 function Has_Compatible_Alignment
582 Expr : Node_Id) return Alignment_Result;
583 -- Obj is an object entity, and expr is a node for an object reference. If
584 -- the alignment of the object referenced by Expr is known to be compatible
585 -- with the alignment of Obj (i.e. is larger or the same), then the result
586 -- is Known_Compatible. If the alignment of the object referenced by Expr
587 -- is known to be less than the alignment of Obj, then Known_Incompatible
588 -- is returned. If neither condition can be reliably established at compile
589 -- time, then Unknown is returned. This is used to determine if alignment
590 -- checks are required for address clauses, and also whether copies must
591 -- be made when objects are passed by reference.
593 -- Note: Known_Incompatible does not mean that at run time the alignment
594 -- of Expr is known to be wrong for Obj, just that it can be determined
595 -- that alignments have been explicitly or implicitly specified which are
596 -- incompatible (whereas Unknown means that even this is not known). The
597 -- appropriate reaction of a caller to Known_Incompatible is to treat it as
598 -- Unknown, but issue a warning that there may be an alignment error.
600 function Has_Declarations (N : Node_Id) return Boolean;
601 -- Determines if the node can have declarations
603 function Has_Discriminant_Dependent_Constraint
604 (Comp : Entity_Id) return Boolean;
605 -- Returns True if and only if Comp has a constrained subtype that depends
606 -- on a discriminant.
608 function Has_Infinities (E : Entity_Id) return Boolean;
609 -- Determines if the range of the floating-point type E includes
610 -- infinities. Returns False if E is not a floating-point type.
612 function Has_Interfaces
614 Use_Full_View : Boolean := True) return Boolean;
615 -- Where T is a concurrent type or a record type, returns true if T covers
616 -- any abstract interface types. In case of private types the argument
617 -- Use_Full_View controls if the check is done using its full view (if
620 function Has_Null_Exclusion (N : Node_Id) return Boolean;
621 -- Determine whether node N has a null exclusion
623 function Has_Overriding_Initialize (T : Entity_Id) return Boolean;
624 -- Predicate to determine whether a controlled type has a user-defined
625 -- Initialize primitive (and, in Ada 2012, whether that primitive is
626 -- non-null), which causes the type to not have preelaborable
629 function Has_Preelaborable_Initialization (E : Entity_Id) return Boolean;
630 -- Return True iff type E has preelaborable initialization as defined in
631 -- Ada 2005 (see AI-161 for details of the definition of this attribute).
633 function Has_Private_Component (Type_Id : Entity_Id) return Boolean;
634 -- Check if a type has a (sub)component of a private type that has not
635 -- yet received a full declaration.
637 function Has_Static_Array_Bounds (Typ : Node_Id) return Boolean;
638 -- Return whether an array type has static bounds
640 function Has_Stream (T : Entity_Id) return Boolean;
641 -- Tests if type T is derived from Ada.Streams.Root_Stream_Type, or in the
642 -- case of a composite type, has a component for which this predicate is
643 -- True, and if so returns True. Otherwise a result of False means that
644 -- there is no Stream type in sight. For a private type, the test is
645 -- applied to the underlying type (or returns False if there is no
648 function Has_Suffix (E : Entity_Id; Suffix : Character) return Boolean;
649 -- Returns true if the last character of E is Suffix. Used in Assertions.
651 function Has_Tagged_Component (Typ : Entity_Id) return Boolean;
652 -- Returns True if Typ is a composite type (array or record) which is
653 -- either itself a tagged type, or has a component (recursively) which is
654 -- a tagged type. Returns False for non-composite type, or if no tagged
655 -- component is present. This function is used to check if "=" has to be
656 -- expanded into a bunch component comparisons.
658 function Implementation_Kind (Subp : Entity_Id) return Name_Id;
659 -- Subp is a subprogram marked with pragma Implemented. Return the specific
660 -- implementation requirement which the pragma imposes. The return value is
661 -- either Name_By_Any, Name_By_Entry or Name_By_Protected_Procedure.
663 function Implements_Interface
664 (Typ_Ent : Entity_Id;
665 Iface_Ent : Entity_Id;
666 Exclude_Parents : Boolean := False) return Boolean;
667 -- Returns true if the Typ_Ent implements interface Iface_Ent
669 function In_Instance return Boolean;
670 -- Returns True if the current scope is within a generic instance
672 function In_Instance_Body return Boolean;
673 -- Returns True if current scope is within the body of an instance, where
674 -- several semantic checks (e.g. accessibility checks) are relaxed.
676 function In_Instance_Not_Visible return Boolean;
677 -- Returns True if current scope is with the private part or the body of
678 -- an instance. Other semantic checks are suppressed in this context.
680 function In_Instance_Visible_Part return Boolean;
681 -- Returns True if current scope is within the visible part of a package
682 -- instance, where several additional semantic checks apply.
684 function In_Package_Body return Boolean;
685 -- Returns True if current scope is within a package body
687 function In_Parameter_Specification (N : Node_Id) return Boolean;
688 -- Returns True if node N belongs to a parameter specification
690 function In_Subprogram_Or_Concurrent_Unit return Boolean;
691 -- Determines if the current scope is within a subprogram compilation unit
692 -- (inside a subprogram declaration, subprogram body, or generic
693 -- subprogram declaration) or within a task or protected body. The test is
694 -- for appearing anywhere within such a construct (that is it does not need
695 -- to be directly within).
697 function In_Visible_Part (Scope_Id : Entity_Id) return Boolean;
698 -- Determine whether a declaration occurs within the visible part of a
699 -- package specification. The package must be on the scope stack, and the
700 -- corresponding private part must not.
702 function Incomplete_Or_Private_View (Typ : Entity_Id) return Entity_Id;
703 -- Given the entity of a type, retrieve the incomplete or private view of
704 -- the same type. Note that Typ may not have a partial view to begin with,
705 -- in that case the function returns Empty.
707 procedure Insert_Explicit_Dereference (N : Node_Id);
708 -- In a context that requires a composite or subprogram type and where a
709 -- prefix is an access type, rewrite the access type node N (which is the
710 -- prefix, e.g. of an indexed component) as an explicit dereference.
712 procedure Inspect_Deferred_Constant_Completion (Decls : List_Id);
713 -- Examine all deferred constants in the declaration list Decls and check
714 -- whether they have been completed by a full constant declaration or an
715 -- Import pragma. Emit the error message if that is not the case.
717 function Is_Actual_Out_Parameter (N : Node_Id) return Boolean;
718 -- Determines if N is an actual parameter of out mode in a subprogram call
720 function Is_Actual_Parameter (N : Node_Id) return Boolean;
721 -- Determines if N is an actual parameter in a subprogram call
723 function Is_Actual_Tagged_Parameter (N : Node_Id) return Boolean;
724 -- Determines if N is an actual parameter of a formal of tagged type in a
727 function Is_Aliased_View (Obj : Node_Id) return Boolean;
728 -- Determine if Obj is an aliased view, i.e. the name of an object to which
729 -- 'Access or 'Unchecked_Access can apply.
731 function Is_Ancestor_Package
733 E2 : Entity_Id) return Boolean;
734 -- Determine whether package E1 is an ancestor of E2
736 function Is_Atomic_Object (N : Node_Id) return Boolean;
737 -- Determines if the given node denotes an atomic object in the sense of
738 -- the legality checks described in RM C.6(12).
740 function Is_Controlling_Limited_Procedure
741 (Proc_Nam : Entity_Id) return Boolean;
742 -- Ada 2005 (AI-345): Determine whether Proc_Nam is a primitive procedure
743 -- of a limited interface with a controlling first parameter.
745 function Is_CPP_Constructor_Call (N : Node_Id) return Boolean;
746 -- Returns True if N is a call to a CPP constructor
748 function Is_Dependent_Component_Of_Mutable_Object
749 (Object : Node_Id) return Boolean;
750 -- Returns True if Object is the name of a subcomponent that depends on
751 -- discriminants of a variable whose nominal subtype is unconstrained and
752 -- not indefinite, and the variable is not aliased. Otherwise returns
753 -- False. The nodes passed to this function are assumed to denote objects.
755 function Is_Dereferenced (N : Node_Id) return Boolean;
756 -- N is a subexpression node of an access type. This function returns true
757 -- if N appears as the prefix of a node that does a dereference of the
758 -- access value (selected/indexed component, explicit dereference or a
759 -- slice), and false otherwise.
761 function Is_Descendent_Of (T1 : Entity_Id; T2 : Entity_Id) return Boolean;
762 -- Returns True if type T1 is a descendent of type T2, and false otherwise.
763 -- This is the RM definition, a type is a descendent of another type if it
764 -- is the same type or is derived from a descendent of the other type.
766 function Is_Concurrent_Interface (T : Entity_Id) return Boolean;
767 -- First determine whether type T is an interface and then check whether
768 -- it is of protected, synchronized or task kind.
770 function Is_Expression_Function (Subp : Entity_Id) return Boolean;
771 -- Predicate to determine whether a function entity comes from a rewritten
772 -- expression function, and should be inlined unconditionally.
774 function Is_False (U : Uint) return Boolean;
775 pragma Inline (Is_False);
776 -- The argument is a Uint value which is the Boolean'Pos value of a Boolean
777 -- operand (i.e. is either 0 for False, or 1 for True). This function tests
778 -- if it is False (i.e. zero).
780 function Is_Fixed_Model_Number (U : Ureal; T : Entity_Id) return Boolean;
781 -- Returns True iff the number U is a model number of the fixed-point type
782 -- T, i.e. if it is an exact multiple of Small.
784 function Is_Fully_Initialized_Type (Typ : Entity_Id) return Boolean;
785 -- Typ is a type entity. This function returns true if this type is fully
786 -- initialized, meaning that an object of the type is fully initialized.
787 -- Note that initialization resulting from use of pragma Normalized_Scalars
788 -- does not count. Note that this is only used for the purpose of issuing
789 -- warnings for objects that are potentially referenced uninitialized. This
790 -- means that the result returned is not crucial, but should err on the
791 -- side of thinking things are fully initialized if it does not know.
793 function Is_Inherited_Operation (E : Entity_Id) return Boolean;
794 -- E is a subprogram. Return True is E is an implicit operation inherited
795 -- by a derived type declaration.
797 function Is_Inherited_Operation_For_Type
798 (E : Entity_Id; Typ : Entity_Id) return Boolean;
799 -- E is a subprogram. Return True is E is an implicit operation inherited
800 -- by the derived type declaration for type Typ.
802 function Is_LHS (N : Node_Id) return Boolean;
803 -- Returns True iff N is used as Name in an assignment statement
805 function Is_Library_Level_Entity (E : Entity_Id) return Boolean;
806 -- A library-level declaration is one that is accessible from Standard,
807 -- i.e. a library unit or an entity declared in a library package.
809 function Is_Local_Variable_Reference (Expr : Node_Id) return Boolean;
810 -- Determines whether Expr is a reference to a variable or IN OUT mode
811 -- parameter of the current enclosing subprogram.
812 -- Why are OUT parameters not considered here ???
814 function Is_Object_Reference (N : Node_Id) return Boolean;
815 -- Determines if the tree referenced by N represents an object. Both
816 -- variable and constant objects return True (compare Is_Variable).
818 function Is_OK_Variable_For_Out_Formal (AV : Node_Id) return Boolean;
819 -- Used to test if AV is an acceptable formal for an OUT or IN OUT formal.
820 -- Note that the Is_Variable function is not quite the right test because
821 -- this is a case in which conversions whose expression is a variable (in
822 -- the Is_Variable sense) with a non-tagged type target are considered view
823 -- conversions and hence variables.
825 function Is_Partially_Initialized_Type
827 Include_Implicit : Boolean := True) return Boolean;
828 -- Typ is a type entity. This function returns true if this type is partly
829 -- initialized, meaning that an object of the type is at least partly
830 -- initialized (in particular in the record case, that at least one
831 -- component has an initialization expression). Note that initialization
832 -- resulting from the use of pragma Normalized_Scalars does not count.
833 -- Include_Implicit controls whether implicit initialization of access
834 -- values to null, and of discriminant values, is counted as making the
835 -- type be partially initialized. For the default setting of True, these
836 -- implicit cases do count, and discriminated types or types containing
837 -- access values not explicitly initialized will return True. Otherwise
838 -- if Include_Implicit is False, these cases do not count as making the
839 -- type be partially initialized.
841 function Is_Potentially_Persistent_Type (T : Entity_Id) return Boolean;
842 -- Determines if type T is a potentially persistent type. A potentially
843 -- persistent type is defined (recursively) as a scalar type, a non-tagged
844 -- record whose components are all of a potentially persistent type, or an
845 -- array with all static constraints whose component type is potentially
846 -- persistent. A private type is potentially persistent if the full type
847 -- is potentially persistent.
849 function Is_Protected_Self_Reference (N : Node_Id) return Boolean;
850 -- Return True if node N denotes a protected type name which represents
851 -- the current instance of a protected object according to RM 9.4(21/2).
853 function Is_RCI_Pkg_Spec_Or_Body (Cunit : Node_Id) return Boolean;
854 -- Return True if a compilation unit is the specification or the
855 -- body of a remote call interface package.
857 function Is_Remote_Access_To_Class_Wide_Type (E : Entity_Id) return Boolean;
858 -- Return True if E is a remote access-to-class-wide type
860 function Is_Remote_Access_To_Subprogram_Type (E : Entity_Id) return Boolean;
861 -- Return True if E is a remote access to subprogram type
863 function Is_Remote_Call (N : Node_Id) return Boolean;
864 -- Return True if N denotes a potentially remote call
866 function Is_Renamed_Entry (Proc_Nam : Entity_Id) return Boolean;
867 -- Return True if Proc_Nam is a procedure renaming of an entry
869 function Is_Selector_Name (N : Node_Id) return Boolean;
870 -- Given an N_Identifier node N, determines if it is a Selector_Name.
871 -- As described in Sinfo, Selector_Names are special because they
872 -- represent use of the N_Identifier node for a true identifier, when
873 -- normally such nodes represent a direct name.
875 function Is_SPARK_Initialization_Expr (N : Node_Id) return Boolean;
876 -- Determines if the tree referenced by N represents an initialization
877 -- expression in SPARK, suitable for initializing an object in an object
880 function Is_SPARK_Object_Reference (N : Node_Id) return Boolean;
881 -- Determines if the tree referenced by N represents an object in SPARK
883 function Is_Statement (N : Node_Id) return Boolean;
884 pragma Inline (Is_Statement);
885 -- Check if the node N is a statement node. Note that this includes
886 -- the case of procedure call statements (unlike the direct use of
887 -- the N_Statement_Other_Than_Procedure_Call subtype from Sinfo).
888 -- Note that a label is *not* a statement, and will return False.
890 function Is_Subprogram_Stub_Without_Prior_Declaration
891 (N : Node_Id) return Boolean;
892 -- Return True if N is a subprogram stub with no prior subprogram
895 function Is_Synchronized_Tagged_Type (E : Entity_Id) return Boolean;
896 -- Returns True if E is a synchronized tagged type (AARM 3.9.4 (6/2))
898 function Is_Transfer (N : Node_Id) return Boolean;
899 -- Returns True if the node N is a statement which is known to cause an
900 -- unconditional transfer of control at runtime, i.e. the following
901 -- statement definitely will not be executed.
903 function Is_True (U : Uint) return Boolean;
904 pragma Inline (Is_True);
905 -- The argument is a Uint value which is the Boolean'Pos value of a Boolean
906 -- operand (i.e. is either 0 for False, or 1 for True). This function tests
907 -- if it is True (i.e. non-zero).
909 function Is_Universal_Numeric_Type (T : Entity_Id) return Boolean;
910 pragma Inline (Is_Universal_Numeric_Type);
911 -- True if T is Universal_Integer or Universal_Real
913 function Is_Value_Type (T : Entity_Id) return Boolean;
914 -- Returns true if type T represents a value type. This is only relevant to
915 -- CIL, will always return false for other targets. A value type is a CIL
916 -- object that is accessed directly, as opposed to the other CIL objects
917 -- that are accessed through managed pointers.
919 function Is_VMS_Operator (Op : Entity_Id) return Boolean;
920 -- Determine whether an operator is one of the intrinsics defined
921 -- in the DEC system extension.
923 function Is_Delegate (T : Entity_Id) return Boolean;
924 -- Returns true if type T represents a delegate. A Delegate is the CIL
925 -- object used to represent access-to-subprogram types. This is only
926 -- relevant to CIL, will always return false for other targets.
930 Use_Original_Node : Boolean := True) return Boolean;
931 -- Determines if the tree referenced by N represents a variable, i.e. can
932 -- appear on the left side of an assignment. There is one situation (formal
933 -- parameters) in which non-tagged type conversions are also considered
934 -- variables, but Is_Variable returns False for such cases, since it has
935 -- no knowledge of the context. Note that this is the point at which
936 -- Assignment_OK is checked, and True is returned for any tree thus marked.
937 -- Use_Original_Node is used to perform the test on Original_Node (N). By
938 -- default is True since this routine is commonly invoked as part of the
939 -- semantic analysis and it must not be disturbed by the rewriten nodes.
941 function Is_Visibly_Controlled (T : Entity_Id) return Boolean;
942 -- Check whether T is derived from a visibly controlled type. This is true
943 -- if the root type is declared in Ada.Finalization. If T is derived
944 -- instead from a private type whose full view is controlled, an explicit
945 -- Initialize/Adjust/Finalize subprogram does not override the inherited
948 function Is_Volatile_Object (N : Node_Id) return Boolean;
949 -- Determines if the given node denotes an volatile object in the sense of
950 -- the legality checks described in RM C.6(12). Note that the test here is
951 -- for something actually declared as volatile, not for an object that gets
952 -- treated as volatile (see Einfo.Treat_As_Volatile).
954 procedure Kill_Current_Values (Last_Assignment_Only : Boolean := False);
955 -- This procedure is called to clear all constant indications from all
956 -- entities in the current scope and in any parent scopes if the current
957 -- scope is a block or a package (and that recursion continues to the top
958 -- scope that is not a block or a package). This is used when the
959 -- sequential flow-of-control assumption is violated (occurrence of a
960 -- label, head of a loop, or start of an exception handler). The effect of
961 -- the call is to clear the Constant_Value field (but we do not need to
962 -- clear the Is_True_Constant flag, since that only gets reset if there
963 -- really is an assignment somewhere in the entity scope). This procedure
964 -- also calls Kill_All_Checks, since this is a special case of needing to
965 -- forget saved values. This procedure also clears the Is_Known_Null and
966 -- Is_Known_Non_Null and Is_Known_Valid flags in variables, constants or
967 -- parameters since these are also not known to be trustable any more.
969 -- The Last_Assignment_Only flag is set True to clear only Last_Assignment
970 -- fields and leave other fields unchanged. This is used when we encounter
971 -- an unconditional flow of control change (return, goto, raise). In such
972 -- cases we don't need to clear the current values, since it may be that
973 -- the flow of control change occurs in a conditional context, and if it
974 -- is not taken, then it is just fine to keep the current values. But the
975 -- Last_Assignment field is different, if we have a sequence assign-to-v,
976 -- conditional-return, assign-to-v, we do not want to complain that the
977 -- second assignment clobbers the first.
979 procedure Kill_Current_Values
981 Last_Assignment_Only : Boolean := False);
982 -- This performs the same processing as described above for the form with
983 -- no argument, but for the specific entity given. The call has no effect
984 -- if the entity Ent is not for an object. Last_Assignment_Only has the
985 -- same meaning as for the call with no Ent.
987 procedure Kill_Size_Check_Code (E : Entity_Id);
988 -- Called when an address clause or pragma Import is applied to an entity.
989 -- If the entity is a variable or a constant, and size check code is
990 -- present, this size check code is killed, since the object will not be
991 -- allocated by the program.
993 function Known_To_Be_Assigned (N : Node_Id) return Boolean;
994 -- The node N is an entity reference. This function determines whether the
995 -- reference is for sure an assignment of the entity, returning True if
996 -- so. This differs from May_Be_Lvalue in that it defaults in the other
997 -- direction. Cases which may possibly be assignments but are not known to
998 -- be may return True from May_Be_Lvalue, but False from this function.
1000 function Last_Source_Statement (HSS : Node_Id) return Node_Id;
1001 -- HSS is a handled statement sequence. This function returns the last
1002 -- statement in Statements (HSS) that has Comes_From_Source set. If no
1003 -- such statement exists, Empty is returned.
1005 function Make_Simple_Return_Statement
1007 Expression : Node_Id := Empty) return Node_Id
1008 renames Make_Return_Statement;
1009 -- See Sinfo. We rename Make_Return_Statement to the correct Ada 2005
1010 -- terminology here. Clients should use Make_Simple_Return_Statement.
1012 function Matching_Static_Array_Bounds
1014 R_Typ : Node_Id) return Boolean;
1015 -- L_Typ and R_Typ are two array types. Returns True when they have the
1016 -- same number of dimensions, and the same static bounds for each index
1019 Make_Return_Statement : constant := -2 ** 33;
1020 -- Attempt to prevent accidental uses of Make_Return_Statement. If this
1021 -- and the one in Nmake are both potentially use-visible, it will cause
1022 -- a compilation error. Note that type and value are irrelevant.
1024 N_Return_Statement : constant := -2**33;
1025 -- Attempt to prevent accidental uses of N_Return_Statement; similar to
1026 -- Make_Return_Statement above.
1028 procedure Mark_Coextensions (Context_Nod : Node_Id; Root_Nod : Node_Id);
1029 -- Given a node which designates the context of analysis and an origin in
1030 -- the tree, traverse from Root_Nod and mark all allocators as either
1031 -- dynamic or static depending on Context_Nod. Any erroneous marking is
1032 -- cleaned up during resolution.
1034 function May_Be_Lvalue (N : Node_Id) return Boolean;
1035 -- Determines if N could be an lvalue (e.g. an assignment left hand side).
1036 -- An lvalue is defined as any expression which appears in a context where
1037 -- a name is required by the syntax, and the identity, rather than merely
1038 -- the value of the node is needed (for example, the prefix of an Access
1039 -- attribute is in this category). Note that, as implied by the name, this
1040 -- test is conservative. If it cannot be sure that N is NOT an lvalue, then
1041 -- it returns True. It tries hard to get the answer right, but it is hard
1042 -- to guarantee this in all cases. Note that it is more possible to give
1043 -- correct answer if the tree is fully analyzed.
1045 function Needs_One_Actual (E : Entity_Id) return Boolean;
1046 -- Returns True if a function has defaults for all but its first
1047 -- formal. Used in Ada 2005 mode to solve the syntactic ambiguity that
1048 -- results from an indexing of a function call written in prefix form.
1050 function New_Copy_List_Tree (List : List_Id) return List_Id;
1051 -- Copy recursively an analyzed list of nodes. Uses New_Copy_Tree defined
1052 -- below. As for New_Copy_Tree, it is illegal to attempt to copy extended
1053 -- nodes (entities) either directly or indirectly using this function.
1055 function New_Copy_Tree
1057 Map : Elist_Id := No_Elist;
1058 New_Sloc : Source_Ptr := No_Location;
1059 New_Scope : Entity_Id := Empty) return Node_Id;
1060 -- Given a node that is the root of a subtree, Copy_Tree copies the entire
1061 -- syntactic subtree, including recursively any descendents whose parent
1062 -- field references a copied node (descendents not linked to a copied node
1063 -- by the parent field are not copied, instead the copied tree references
1064 -- the same descendent as the original in this case, which is appropriate
1065 -- for non-syntactic fields such as Etype). The parent pointers in the
1066 -- copy are properly set. Copy_Tree (Empty/Error) returns Empty/Error.
1067 -- The one exception to the rule of not copying semantic fields is that
1068 -- any implicit types attached to the subtree are duplicated, so that
1069 -- the copy contains a distinct set of implicit type entities. Thus this
1070 -- function is used when it is necessary to duplicate an analyzed tree,
1071 -- declared in the same or some other compilation unit. This function is
1072 -- declared here rather than in atree because it uses semantic information
1073 -- in particular concerning the structure of itypes and the generation of
1076 -- The Map argument, if set to a non-empty Elist, specifies a set of
1077 -- mappings to be applied to entities in the tree. The map has the form:
1080 -- new entity to replace references to entity 1
1082 -- new entity to replace references to entity 2
1085 -- The call destroys the contents of Map in this case
1087 -- The parameter New_Sloc, if set to a value other than No_Location, is
1088 -- used as the Sloc value for all nodes in the new copy. If New_Sloc is
1089 -- set to its default value No_Location, then the Sloc values of the
1090 -- nodes in the copy are simply copied from the corresponding original.
1092 -- The Comes_From_Source indication is unchanged if New_Sloc is set to
1093 -- the default No_Location value, but is reset if New_Sloc is given, since
1094 -- in this case the result clearly is neither a source node or an exact
1095 -- copy of a source node.
1097 -- The parameter New_Scope, if set to a value other than Empty, is the
1098 -- value to use as the Scope for any Itypes that are copied. The most
1099 -- typical value for this parameter, if given, is Current_Scope.
1101 function New_External_Entity
1102 (Kind : Entity_Kind;
1103 Scope_Id : Entity_Id;
1104 Sloc_Value : Source_Ptr;
1105 Related_Id : Entity_Id;
1107 Suffix_Index : Nat := 0;
1108 Prefix : Character := ' ') return Entity_Id;
1109 -- This function creates an N_Defining_Identifier node for an internal
1110 -- created entity, such as an implicit type or subtype, or a record
1111 -- initialization procedure. The entity name is constructed with a call
1112 -- to New_External_Name (Related_Id, Suffix, Suffix_Index, Prefix), so
1113 -- that the generated name may be referenced as a public entry, and the
1114 -- Is_Public flag is set if needed (using Set_Public_Status). If the
1115 -- entity is for a type or subtype, the size/align fields are initialized
1116 -- to unknown (Uint_0).
1118 function New_Internal_Entity
1119 (Kind : Entity_Kind;
1120 Scope_Id : Entity_Id;
1121 Sloc_Value : Source_Ptr;
1122 Id_Char : Character) return Entity_Id;
1123 -- This function is similar to New_External_Entity, except that the
1124 -- name is constructed by New_Internal_Name (Id_Char). This is used
1125 -- when the resulting entity does not have to be referenced as a
1126 -- public entity (and in this case Is_Public is not set).
1128 procedure Next_Actual (Actual_Id : in out Node_Id);
1129 pragma Inline (Next_Actual);
1130 -- Next_Actual (N) is equivalent to N := Next_Actual (N). Note that we
1131 -- inline this procedural form, but not the functional form that follows.
1133 function Next_Actual (Actual_Id : Node_Id) return Node_Id;
1134 -- Find next actual parameter in declaration order. As described for
1135 -- First_Actual, this is the next actual in the declaration order, not
1136 -- the call order, so this does not correspond to simply taking the
1137 -- next entry of the Parameter_Associations list. The argument is an
1138 -- actual previously returned by a call to First_Actual or Next_Actual.
1139 -- Note that the result produced is always an expression, not a parameter
1140 -- association node, even if named notation was used.
1142 procedure Normalize_Actuals
1146 Success : out Boolean);
1147 -- Reorders lists of actuals according to names of formals, value returned
1148 -- in Success indicates success of reordering. For more details, see body.
1149 -- Errors are reported only if Report is set to True.
1151 procedure Note_Possible_Modification (N : Node_Id; Sure : Boolean);
1152 -- This routine is called if the sub-expression N maybe the target of
1153 -- an assignment (e.g. it is the left side of an assignment, used as
1154 -- an out parameters, or used as prefixes of access attributes). It
1155 -- sets May_Be_Modified in the associated entity if there is one,
1156 -- taking into account the rule that in the case of renamed objects,
1157 -- it is the flag in the renamed object that must be set.
1159 -- The parameter Sure is set True if the modification is sure to occur
1160 -- (e.g. target of assignment, or out parameter), and to False if the
1161 -- modification is only potential (e.g. address of entity taken).
1163 function Original_Corresponding_Operation (S : Entity_Id) return Entity_Id;
1164 -- [Ada 2012: AI05-0125-1]: If S is an inherited dispatching primitive S2,
1165 -- or overrides an inherited dispatching primitive S2, the original
1166 -- corresponding operation of S is the original corresponding operation of
1167 -- S2. Otherwise, it is S itself.
1169 function Object_Access_Level (Obj : Node_Id) return Uint;
1170 -- Return the accessibility level of the view of the object Obj.
1171 -- For convenience, qualified expressions applied to object names
1172 -- are also allowed as actuals for this function.
1174 function Primitive_Names_Match (E1, E2 : Entity_Id) return Boolean;
1175 -- Returns True if the names of both entities correspond with matching
1176 -- primitives. This routine includes support for the case in which one
1177 -- or both entities correspond with entities built by Derive_Subprogram
1178 -- with a special name to avoid being overridden (i.e. return true in case
1179 -- of entities with names "nameP" and "name" or vice versa).
1181 function Private_Component (Type_Id : Entity_Id) return Entity_Id;
1182 -- Returns some private component (if any) of the given Type_Id.
1183 -- Used to enforce the rules on visibility of operations on composite
1184 -- types, that depend on the full view of the component type. For a
1185 -- record type there may be several such components, we just return
1188 procedure Process_End_Label
1192 -- N is a node whose End_Label is to be processed, generating all
1193 -- appropriate cross-reference entries, and performing style checks
1194 -- for any identifier references in the end label. Typ is either
1195 -- 'e' or 't indicating the type of the cross-reference entity
1196 -- (e for spec, t for body, see Lib.Xref spec for details). The
1197 -- parameter Ent gives the entity to which the End_Label refers,
1198 -- and to which cross-references are to be generated.
1200 function References_Generic_Formal_Type (N : Node_Id) return Boolean;
1201 -- Returns True if the expression Expr contains any references to a
1202 -- generic type. This can only happen within a generic template.
1204 procedure Remove_Homonym (E : Entity_Id);
1205 -- Removes E from the homonym chain
1207 function Rep_To_Pos_Flag (E : Entity_Id; Loc : Source_Ptr) return Node_Id;
1208 -- This is used to construct the second argument in a call to Rep_To_Pos
1209 -- which is Standard_True if range checks are enabled (E is an entity to
1210 -- which the Range_Checks_Suppressed test is applied), and Standard_False
1211 -- if range checks are suppressed. Loc is the location for the node that
1212 -- is returned (which is a New_Occurrence of the appropriate entity).
1214 -- Note: one might think that it would be fine to always use True and
1215 -- to ignore the suppress in this case, but it is generally better to
1216 -- believe a request to suppress exceptions if possible, and further
1217 -- more there is at least one case in the generated code (the code for
1218 -- array assignment in a loop) that depends on this suppression.
1220 procedure Require_Entity (N : Node_Id);
1221 -- N is a node which should have an entity value if it is an entity name.
1222 -- If not, then check if there were previous errors. If so, just fill
1223 -- in with Any_Id and ignore. Otherwise signal a program error exception.
1224 -- This is used as a defense mechanism against ill-formed trees caused by
1225 -- previous errors (particularly in -gnatq mode).
1227 function Requires_Transient_Scope (Id : Entity_Id) return Boolean;
1228 -- Id is a type entity. The result is True when temporaries of this type
1229 -- need to be wrapped in a transient scope to be reclaimed properly when a
1230 -- secondary stack is in use. Examples of types requiring such wrapping are
1231 -- controlled types and variable-sized types including unconstrained
1234 procedure Reset_Analyzed_Flags (N : Node_Id);
1235 -- Reset the Analyzed flags in all nodes of the tree whose root is N
1237 function Safe_To_Capture_Value
1240 Cond : Boolean := False) return Boolean;
1241 -- The caller is interested in capturing a value (either the current value,
1242 -- or an indication that the value is non-null) for the given entity Ent.
1243 -- This value can only be captured if sequential execution semantics can be
1244 -- properly guaranteed so that a subsequent reference will indeed be sure
1245 -- that this current value indication is correct. The node N is the
1246 -- construct which resulted in the possible capture of the value (this
1247 -- is used to check if we are in a conditional).
1249 -- Cond is used to skip the test for being inside a conditional. It is used
1250 -- in the case of capturing values from if/while tests, which already do a
1251 -- proper job of handling scoping issues without this help.
1253 -- The only entities whose values can be captured are OUT and IN OUT formal
1254 -- parameters, and variables unless Cond is True, in which case we also
1255 -- allow IN formals, loop parameters and constants, where we cannot ever
1256 -- capture actual value information, but we can capture conditional tests.
1258 function Same_Name (N1, N2 : Node_Id) return Boolean;
1259 -- Determine if two (possibly expanded) names are the same name. This is
1260 -- a purely syntactic test, and N1 and N2 need not be analyzed.
1262 function Same_Object (Node1, Node2 : Node_Id) return Boolean;
1263 -- Determine if Node1 and Node2 are known to designate the same object.
1264 -- This is a semantic test and both nodes must be fully analyzed. A result
1265 -- of True is decisively correct. A result of False does not necessarily
1266 -- mean that different objects are designated, just that this could not
1267 -- be reliably determined at compile time.
1269 function Same_Type (T1, T2 : Entity_Id) return Boolean;
1270 -- Determines if T1 and T2 represent exactly the same type. Two types
1271 -- are the same if they are identical, or if one is an unconstrained
1272 -- subtype of the other, or they are both common subtypes of the same
1273 -- type with identical constraints. The result returned is conservative.
1274 -- It is True if the types are known to be the same, but a result of
1275 -- False is indecisive (e.g. the compiler may not be able to tell that
1276 -- two constraints are identical).
1278 function Same_Value (Node1, Node2 : Node_Id) return Boolean;
1279 -- Determines if Node1 and Node2 are known to be the same value, which is
1280 -- true if they are both compile time known values and have the same value,
1281 -- or if they are the same object (in the sense of function Same_Object).
1282 -- A result of False does not necessarily mean they have different values,
1283 -- just that it is not possible to determine they have the same value.
1285 function Scope_Within_Or_Same (Scope1, Scope2 : Entity_Id) return Boolean;
1286 -- Determines if the entity Scope1 is the same as Scope2, or if it is
1287 -- inside it, where both entities represent scopes. Note that scopes
1288 -- are only partially ordered, so Scope_Within_Or_Same (A,B) and
1289 -- Scope_Within_Or_Same (B,A) can both be False for a given pair A,B.
1291 procedure Save_Actual (N : Node_Id; Writable : Boolean := False);
1292 -- Enter an actual in a call in a table global, for subsequent check of
1293 -- possible order dependence in the presence of IN OUT parameters for
1294 -- functions in Ada 2012 (or access parameters in older language versions).
1296 function Scope_Within (Scope1, Scope2 : Entity_Id) return Boolean;
1297 -- Like Scope_Within_Or_Same, except that this function returns
1298 -- False in the case where Scope1 and Scope2 are the same scope.
1300 procedure Set_Convention (E : Entity_Id; Val : Convention_Id);
1301 -- Same as Basic_Set_Convention, but with an extra check for access types.
1302 -- In particular, if E is an access-to-subprogram type, and Val is a
1303 -- foreign convention, then we set Can_Use_Internal_Rep to False on E.
1305 procedure Set_Current_Entity (E : Entity_Id);
1306 pragma Inline (Set_Current_Entity);
1307 -- Establish the entity E as the currently visible definition of its
1308 -- associated name (i.e. the Node_Id associated with its name).
1310 procedure Set_Debug_Info_Needed (T : Entity_Id);
1311 -- Sets the Debug_Info_Needed flag on entity T , and also on any entities
1312 -- that are needed by T (for an object, the type of the object is needed,
1313 -- and for a type, various subsidiary types are needed -- see body for
1314 -- details). Never has any effect on T if the Debug_Info_Off flag is set.
1315 -- This routine should always be used instead of Set_Needs_Debug_Info to
1316 -- ensure that subsidiary entities are properly handled.
1318 procedure Set_Entity_With_Style_Check (N : Node_Id; Val : Entity_Id);
1319 -- This procedure has the same calling sequence as Set_Entity, but
1320 -- if Style_Check is set, then it calls a style checking routine which
1321 -- can check identifier spelling style.
1323 procedure Set_Name_Entity_Id (Id : Name_Id; Val : Entity_Id);
1324 pragma Inline (Set_Name_Entity_Id);
1325 -- Sets the Entity_Id value associated with the given name, which is the
1326 -- Id of the innermost visible entity with the given name. See the body
1327 -- of package Sem_Ch8 for further details on the handling of visibility.
1329 procedure Set_Next_Actual (Ass1_Id : Node_Id; Ass2_Id : Node_Id);
1330 -- The arguments may be parameter associations, whose descendants
1331 -- are the optional formal name and the actual parameter. Positional
1332 -- parameters are already members of a list, and do not need to be
1333 -- chained separately. See also First_Actual and Next_Actual.
1335 procedure Set_Optimize_Alignment_Flags (E : Entity_Id);
1336 pragma Inline (Set_Optimize_Alignment_Flags);
1337 -- Sets Optimize_Alignment_Space/Time flags in E from current settings
1339 procedure Set_Public_Status (Id : Entity_Id);
1340 -- If an entity (visible or otherwise) is defined in a library
1341 -- package, or a package that is itself public, then this subprogram
1342 -- labels the entity public as well.
1344 procedure Set_Referenced_Modified (N : Node_Id; Out_Param : Boolean);
1345 -- N is the node for either a left hand side (Out_Param set to False),
1346 -- or an Out or In_Out parameter (Out_Param set to True). If there is
1347 -- an assignable entity being referenced, then the appropriate flag
1348 -- (Referenced_As_LHS if Out_Param is False, Referenced_As_Out_Parameter
1349 -- if Out_Param is True) is set True, and the other flag set False.
1351 procedure Set_Scope_Is_Transient (V : Boolean := True);
1352 -- Set the flag Is_Transient of the current scope
1354 procedure Set_Size_Info (T1, T2 : Entity_Id);
1355 pragma Inline (Set_Size_Info);
1356 -- Copies the Esize field and Has_Biased_Representation flag from sub(type)
1357 -- entity T2 to (sub)type entity T1. Also copies the Is_Unsigned_Type flag
1358 -- in the fixed-point and discrete cases, and also copies the alignment
1359 -- value from T2 to T1. It does NOT copy the RM_Size field, which must be
1360 -- separately set if this is required to be copied also.
1362 function Scope_Is_Transient return Boolean;
1363 -- True if the current scope is transient
1365 function Static_Boolean (N : Node_Id) return Uint;
1366 -- This function analyzes the given expression node and then resolves it
1367 -- as Standard.Boolean. If the result is static, then Uint_1 or Uint_0 is
1368 -- returned corresponding to the value, otherwise an error message is
1369 -- output and No_Uint is returned.
1371 function Static_Integer (N : Node_Id) return Uint;
1372 -- This function analyzes the given expression node and then resolves it
1373 -- as any integer type. If the result is static, then the value of the
1374 -- universal expression is returned, otherwise an error message is output
1375 -- and a value of No_Uint is returned.
1377 function Statically_Different (E1, E2 : Node_Id) return Boolean;
1378 -- Return True if it can be statically determined that the Expressions
1379 -- E1 and E2 refer to different objects
1381 function Subprogram_Access_Level (Subp : Entity_Id) return Uint;
1382 -- Return the accessibility level of the view denoted by Subp
1384 procedure Trace_Scope (N : Node_Id; E : Entity_Id; Msg : String);
1385 -- Print debugging information on entry to each unit being analyzed
1387 procedure Transfer_Entities (From : Entity_Id; To : Entity_Id);
1388 -- Move a list of entities from one scope to another, and recompute
1389 -- Is_Public based upon the new scope.
1391 function Type_Access_Level (Typ : Entity_Id) return Uint;
1392 -- Return the accessibility level of Typ
1394 function Type_Without_Stream_Operation
1396 Op : TSS_Name_Type := TSS_Null) return Entity_Id;
1397 -- AI05-0161: In Ada 2012, if the restriction No_Default_Stream_Attributes
1398 -- is active then we cannot generate stream subprograms for composite types
1399 -- with elementary subcomponents that lack user-defined stream subprograms.
1400 -- This predicate determines whether a type has such an elementary
1401 -- subcomponent. If Op is TSS_Null, a type that lacks either Read or Write
1402 -- prevents the construction of a composite stream operation. If Op is
1403 -- specified we check only for the given stream operation.
1405 function Unique_Defining_Entity (N : Node_Id) return Entity_Id;
1406 -- Return the entity which represents declaration N, so that matching
1407 -- declaration and body have the same entity.
1409 function Unique_Name (E : Entity_Id) return String;
1410 -- Return a unique name for entity E, which could be used to identify E
1411 -- across compilation units.
1413 function Unit_Declaration_Node (Unit_Id : Entity_Id) return Node_Id;
1414 -- Unit_Id is the simple name of a program unit, this function returns the
1415 -- corresponding xxx_Declaration node for the entity. Also applies to the
1416 -- body entities for subprograms, tasks and protected units, in which case
1417 -- it returns the subprogram, task or protected body node for it. The unit
1418 -- may be a child unit with any number of ancestors.
1420 function Unit_Is_Visible (U : Entity_Id) return Boolean;
1421 -- Determine whether a compilation unit is visible in the current context,
1422 -- because there is a with_clause that makes the unit available. Used to
1423 -- provide better messages on common visiblity errors on operators.
1425 function Universal_Interpretation (Opnd : Node_Id) return Entity_Id;
1426 -- Yields Universal_Integer or Universal_Real if this is a candidate
1428 function Unqualify (Expr : Node_Id) return Node_Id;
1429 pragma Inline (Unqualify);
1430 -- Removes any qualifications from Expr. For example, for T1'(T2'(X)), this
1431 -- returns X. If Expr is not a qualified expression, returns Expr.
1433 function Visible_Ancestors (Typ : Entity_Id) return Elist_Id;
1434 -- [Ada 2012:AI-0125-1]: Collect all the visible parents and progenitors
1435 -- of a type extension or private extension declaration. If the full-view
1436 -- of private parents and progenitors is available then it is used to
1437 -- generate the list of visible ancestors; otherwise their partial
1438 -- view is added to the resulting list.
1440 function Within_Init_Proc return Boolean;
1441 -- Determines if Current_Scope is within an init proc
1443 procedure Wrong_Type (Expr : Node_Id; Expected_Type : Entity_Id);
1444 -- Output error message for incorrectly typed expression. Expr is the node
1445 -- for the incorrectly typed construct (Etype (Expr) is the type found),
1446 -- and Expected_Type is the entity for the expected type. Note that Expr
1447 -- does not have to be a subexpression, anything with an Etype field may