File : sem_util.ads
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- S E M _ U T I L --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 1992-2016, Free Software Foundation, Inc. --
10 -- --
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. --
20 -- --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
23 -- --
24 ------------------------------------------------------------------------------
25
26 -- Package containing utility procedures used throughout the semantics
27
28 with Einfo; use Einfo;
29 with Exp_Tss; use Exp_Tss;
30 with Namet; use Namet;
31 with Opt; use Opt;
32 with Snames; use Snames;
33 with Types; use Types;
34 with Uintp; use Uintp;
35 with Urealp; use Urealp;
36
37 package Sem_Util is
38
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.
42
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
45 -- freeze node of E.
46
47 procedure Add_Block_Identifier (N : Node_Id; Id : out Entity_Id);
48 -- Given a block statement N, generate an internal E_Block label and make
49 -- it the identifier of the block. Id denotes the generated entity. If the
50 -- block already has an identifier, Id returns the entity of its label.
51
52 procedure Add_Global_Declaration (N : Node_Id);
53 -- These procedures adds a declaration N at the library level, to be
54 -- elaborated before any other code in the unit. It is used for example
55 -- for the entity that marks whether a unit has been elaborated. The
56 -- declaration is added to the Declarations list of the Aux_Decls_Node
57 -- for the current unit. The declarations are added in the current scope,
58 -- so the caller should push a new scope as required before the call.
59
60 function Add_Suffix (E : Entity_Id; Suffix : Character) return Name_Id;
61 -- Returns the name of E adding Suffix
62
63 function Address_Integer_Convert_OK (T1, T2 : Entity_Id) return Boolean;
64 -- Given two types, returns True if we are in Allow_Integer_Address mode
65 -- and one of the types is (a descendant of) System.Address (and this type
66 -- is private), and the other type is any integer type.
67
68 function Address_Value (N : Node_Id) return Node_Id;
69 -- Return the underlying value of the expression N of an address clause
70
71 function Addressable (V : Uint) return Boolean;
72 function Addressable (V : Int) return Boolean;
73 pragma Inline (Addressable);
74 -- Returns True if the value of V is the word size or an addressable factor
75 -- of the word size (typically 8, 16, 32 or 64).
76
77 procedure Aggregate_Constraint_Checks
78 (Exp : Node_Id;
79 Check_Typ : Entity_Id);
80 -- Checks expression Exp against subtype Check_Typ. If Exp is an aggregate
81 -- and Check_Typ a constrained record type with discriminants, we generate
82 -- the appropriate discriminant checks. If Exp is an array aggregate then
83 -- emit the appropriate length checks. If Exp is a scalar type, or a string
84 -- literal, Exp is changed into Check_Typ'(Exp) to ensure that range checks
85 -- are performed at run time. Also used for expressions in the argument of
86 -- 'Update, which shares some of the features of an aggregate.
87
88 function Alignment_In_Bits (E : Entity_Id) return Uint;
89 -- If the alignment of the type or object E is currently known to the
90 -- compiler, then this function returns the alignment value in bits.
91 -- Otherwise Uint_0 is returned, indicating that the alignment of the
92 -- entity is not yet known to the compiler.
93
94 function All_Composite_Constraints_Static (Constr : Node_Id) return Boolean;
95 -- Used to implement pragma Restrictions (No_Dynamic_Sized_Objects).
96 -- Given a constraint or subtree of a constraint on a composite
97 -- subtype/object, returns True if there are no nonstatic constraints,
98 -- which might cause objects to be created with dynamic size.
99 -- Called for subtype declarations (including implicit ones created for
100 -- subtype indications in object declarations, as well as discriminated
101 -- record aggregate cases). For record aggregates, only records containing
102 -- discriminant-dependent arrays matter, because the discriminants must be
103 -- static when governing a variant part. Access discriminants are
104 -- irrelevant. Also called for array aggregates, but only named notation,
105 -- because those are the only dynamic cases.
106
107 procedure Append_Inherited_Subprogram (S : Entity_Id);
108 -- If the parent of the operation is declared in the visible part of
109 -- the current scope, the inherited operation is visible even though the
110 -- derived type that inherits the operation may be completed in the private
111 -- part of the current package.
112
113 procedure Apply_Compile_Time_Constraint_Error
114 (N : Node_Id;
115 Msg : String;
116 Reason : RT_Exception_Code;
117 Ent : Entity_Id := Empty;
118 Typ : Entity_Id := Empty;
119 Loc : Source_Ptr := No_Location;
120 Rep : Boolean := True;
121 Warn : Boolean := False);
122 -- N is a subexpression which will raise constraint error when evaluated
123 -- at runtime. Msg is a message that explains the reason for raising the
124 -- exception. The last character is ? if the message is always a warning,
125 -- even in Ada 95, and is not a ? if the message represents an illegality
126 -- (because of violation of static expression rules) in Ada 95 (but not
127 -- in Ada 83). Typically this routine posts all messages at the Sloc of
128 -- node N. However, if Loc /= No_Location, Loc is the Sloc used to output
129 -- the message. After posting the appropriate message, and if the flag
130 -- Rep is set, this routine replaces the expression with an appropriate
131 -- N_Raise_Constraint_Error node using the given Reason code. This node
132 -- is then marked as being static if the original node is static, but
133 -- sets the flag Raises_Constraint_Error, preventing further evaluation.
134 -- The error message may contain a } or & insertion character. This
135 -- normally references Etype (N), unless the Ent argument is given
136 -- explicitly, in which case it is used instead. The type of the raise
137 -- node that is built is normally Etype (N), but if the Typ parameter
138 -- is present, this is used instead. Warn is normally False. If it is
139 -- True then the message is treated as a warning even though it does
140 -- not end with a ? (this is used when the caller wants to parameterize
141 -- whether an error or warning is given), or when the message should be
142 -- treated as a warning even when SPARK_Mode is On (which otherwise would
143 -- force an error).
144
145 function Async_Readers_Enabled (Id : Entity_Id) return Boolean;
146 -- Given the entity of an abstract state or a variable, determine whether
147 -- Id is subject to external property Async_Readers and if it is, the
148 -- related expression evaluates to True.
149
150 function Async_Writers_Enabled (Id : Entity_Id) return Boolean;
151 -- Given the entity of an abstract state or a variable, determine whether
152 -- Id is subject to external property Async_Writers and if it is, the
153 -- related expression evaluates to True.
154
155 function Available_Full_View_Of_Component (T : Entity_Id) return Boolean;
156 -- If at the point of declaration an array type has a private or limited
157 -- component, several array operations are not avaiable on the type, and
158 -- the array type is flagged accordingly. If in the immediate scope of
159 -- the array type the component becomes non-private or non-limited, these
160 -- operations become avaiable. This can happen if the scopes of both types
161 -- are open, and the scope of the array is not outside the scope of the
162 -- component.
163
164 procedure Bad_Attribute
165 (N : Node_Id;
166 Nam : Name_Id;
167 Warn : Boolean := False);
168 -- Called when node N is expected to contain a valid attribute name, and
169 -- Nam is found instead. If Warn is set True this is a warning, else this
170 -- is an error.
171
172 procedure Bad_Predicated_Subtype_Use
173 (Msg : String;
174 N : Node_Id;
175 Typ : Entity_Id;
176 Suggest_Static : Boolean := False);
177 -- This is called when Typ, a predicated subtype, is used in a context
178 -- which does not allow the use of a predicated subtype. Msg is passed to
179 -- Error_Msg_FE to output an appropriate message using N as the location,
180 -- and Typ as the entity. The caller must set up any insertions other than
181 -- the & for the type itself. Note that if Typ is a generic actual type,
182 -- then the message will be output as a warning, and a raise Program_Error
183 -- is inserted using Insert_Action with node N as the insertion point. Node
184 -- N also supplies the source location for construction of the raise node.
185 -- If Typ does not have any predicates, the call has no effect. Set flag
186 -- Suggest_Static when the context warrants an advice on how to avoid the
187 -- use error.
188
189 function Bad_Unordered_Enumeration_Reference
190 (N : Node_Id;
191 T : Entity_Id) return Boolean;
192 -- Node N contains a potentially dubious reference to type T, either an
193 -- explicit comparison, or an explicit range. This function returns True
194 -- if the type T is an enumeration type for which No pragma Order has been
195 -- given, and the reference N is not in the same extended source unit as
196 -- the declaration of T.
197
198 function Build_Actual_Subtype
199 (T : Entity_Id;
200 N : Node_Or_Entity_Id) return Node_Id;
201 -- Build an anonymous subtype for an entity or expression, using the
202 -- bounds of the entity or the discriminants of the enclosing record.
203 -- T is the type for which the actual subtype is required, and N is either
204 -- a defining identifier, or any subexpression.
205
206 function Build_Actual_Subtype_Of_Component
207 (T : Entity_Id;
208 N : Node_Id) return Node_Id;
209 -- Determine whether a selected component has a type that depends on
210 -- discriminants, and build actual subtype for it if so.
211
212 function Build_Default_Init_Cond_Call
213 (Loc : Source_Ptr;
214 Obj_Id : Entity_Id;
215 Typ : Entity_Id) return Node_Id;
216 -- Build a call to the default initial condition procedure of type Typ with
217 -- Obj_Id as the actual parameter.
218
219 procedure Build_Default_Init_Cond_Procedure_Bodies (Priv_Decls : List_Id);
220 -- Inspect the contents of private declarations Priv_Decls and build the
221 -- bodies the default initial condition procedures for all types subject
222 -- to pragma Default_Initial_Condition.
223
224 procedure Build_Default_Init_Cond_Procedure_Declaration (Typ : Entity_Id);
225 -- If private type Typ is subject to pragma Default_Initial_Condition,
226 -- build the declaration of the procedure which verifies the assumption
227 -- of the pragma at runtime. The declaration is inserted after the related
228 -- pragma.
229
230 function Build_Default_Subtype
231 (T : Entity_Id;
232 N : Node_Id) return Entity_Id;
233 -- If T is an unconstrained type with defaulted discriminants, build a
234 -- subtype constrained by the default values, insert the subtype
235 -- declaration in the tree before N, and return the entity of that
236 -- subtype. Otherwise, simply return T.
237
238 function Build_Discriminal_Subtype_Of_Component
239 (T : Entity_Id) return Node_Id;
240 -- Determine whether a record component has a type that depends on
241 -- discriminants, and build actual subtype for it if so.
242
243 procedure Build_Elaboration_Entity (N : Node_Id; Spec_Id : Entity_Id);
244 -- Given a compilation unit node N, allocate an elaboration counter for
245 -- the compilation unit, and install it in the Elaboration_Entity field
246 -- of Spec_Id, the entity for the compilation unit.
247
248 procedure Build_Explicit_Dereference
249 (Expr : Node_Id;
250 Disc : Entity_Id);
251 -- AI05-139: Names with implicit dereference. If the expression N is a
252 -- reference type and the context imposes the corresponding designated
253 -- type, convert N into N.Disc.all. Such expressions are always over-
254 -- loaded with both interpretations, and the dereference interpretation
255 -- carries the name of the reference discriminant.
256
257 function Cannot_Raise_Constraint_Error (Expr : Node_Id) return Boolean;
258 -- Returns True if the expression cannot possibly raise Constraint_Error.
259 -- The response is conservative in the sense that a result of False does
260 -- not necessarily mean that CE could be raised, but a response of True
261 -- means that for sure CE cannot be raised.
262
263 procedure Check_Dynamically_Tagged_Expression
264 (Expr : Node_Id;
265 Typ : Entity_Id;
266 Related_Nod : Node_Id);
267 -- Check wrong use of dynamically tagged expression
268
269 procedure Check_Fully_Declared (T : Entity_Id; N : Node_Id);
270 -- Verify that the full declaration of type T has been seen. If not, place
271 -- error message on node N. Used in object declarations, type conversions
272 -- and qualified expressions.
273
274 procedure Check_Function_With_Address_Parameter (Subp_Id : Entity_Id);
275 -- A subprogram that has an Address parameter and is declared in a Pure
276 -- package is not considered Pure, because the parameter may be used as a
277 -- pointer and the referenced data may change even if the address value
278 -- itself does not.
279 -- If the programmer gave an explicit Pure_Function pragma, then we respect
280 -- the pragma and leave the subprogram Pure.
281
282 procedure Check_Function_Writable_Actuals (N : Node_Id);
283 -- (Ada 2012): If the construct N has two or more direct constituents that
284 -- are names or expressions whose evaluation may occur in an arbitrary
285 -- order, at least one of which contains a function call with an in out or
286 -- out parameter, then the construct is legal only if: for each name that
287 -- is passed as a parameter of mode in out or out to some inner function
288 -- call C2 (not including the construct N itself), there is no other name
289 -- anywhere within a direct constituent of the construct C other than
290 -- the one containing C2, that is known to refer to the same object (RM
291 -- 6.4.1(6.17/3)).
292
293 procedure Check_Implicit_Dereference (N : Node_Id; Typ : Entity_Id);
294 -- AI05-139-2: Accessors and iterators for containers. This procedure
295 -- checks whether T is a reference type, and if so it adds an interprettion
296 -- to N whose type is the designated type of the reference_discriminant.
297 -- If N is a generalized indexing operation, the interpretation is added
298 -- both to the corresponding function call, and to the indexing node.
299
300 procedure Check_Internal_Protected_Use (N : Node_Id; Nam : Entity_Id);
301 -- Within a protected function, the current object is a constant, and
302 -- internal calls to a procedure or entry are illegal. Similarly, other
303 -- uses of a protected procedure in a renaming or a generic instantiation
304 -- in the context of a protected function are illegal (AI05-0225).
305
306 procedure Check_Later_Vs_Basic_Declarations
307 (Decls : List_Id;
308 During_Parsing : Boolean);
309 -- If During_Parsing is True, check for misplacement of later vs basic
310 -- declarations in Ada 83. If During_Parsing is False, and the SPARK
311 -- restriction is set, do the same: although SPARK 95 removes the
312 -- distinction between initial and later declarative items, the distinction
313 -- remains in the Examiner (JB01-005). Note that the Examiner does not
314 -- count package declarations in later declarative items.
315
316 procedure Check_No_Hidden_State (Id : Entity_Id);
317 -- Determine whether object or state Id introduces a hidden state. If this
318 -- is the case, emit an error.
319
320 procedure Check_Nonvolatile_Function_Profile (Func_Id : Entity_Id);
321 -- Verify that the profile of nonvolatile function Func_Id does not contain
322 -- effectively volatile parameters or return type.
323
324 procedure Check_Part_Of_Reference (Var_Id : Entity_Id; Ref : Node_Id);
325 -- Verify the legality of reference Ref to variable Var_Id when the
326 -- variable is a constituent of a single protected/task type.
327
328 procedure Check_Potentially_Blocking_Operation (N : Node_Id);
329 -- N is one of the statement forms that is a potentially blocking
330 -- operation. If it appears within a protected action, emit warning.
331
332 procedure Check_Result_And_Post_State (Subp_Id : Entity_Id);
333 -- Determine whether the contract of subprogram Subp_Id mentions attribute
334 -- 'Result and it contains an expression that evaluates differently in pre-
335 -- and post-state.
336
337 procedure Check_State_Refinements
338 (Context : Node_Id;
339 Is_Main_Unit : Boolean := False);
340 -- Verify that all abstract states declared in a block statement, entry
341 -- body, package body, protected body, subprogram body, task body, or a
342 -- package declaration denoted by Context have proper refinement. Emit an
343 -- error if this is not the case. Flag Is_Main_Unit should be set when
344 -- Context denotes the main compilation unit.
345
346 procedure Check_Unused_Body_States (Body_Id : Entity_Id);
347 -- Verify that all abstract states and objects declared in the state space
348 -- of package body Body_Id are used as constituents. Emit an error if this
349 -- is not the case.
350
351 procedure Check_Unprotected_Access
352 (Context : Node_Id;
353 Expr : Node_Id);
354 -- Check whether the expression is a pointer to a protected component,
355 -- and the context is external to the protected operation, to warn against
356 -- a possible unlocked access to data.
357
358 function Collect_Body_States (Body_Id : Entity_Id) return Elist_Id;
359 -- Gather the entities of all abstract states and objects declared in the
360 -- body state space of package body Body_Id.
361
362 procedure Collect_Interfaces
363 (T : Entity_Id;
364 Ifaces_List : out Elist_Id;
365 Exclude_Parents : Boolean := False;
366 Use_Full_View : Boolean := True);
367 -- Ada 2005 (AI-251): Collect whole list of abstract interfaces that are
368 -- directly or indirectly implemented by T. Exclude_Parents is used to
369 -- avoid the addition of inherited interfaces to the generated list.
370 -- Use_Full_View is used to collect the interfaces using the full-view
371 -- (if available).
372
373 procedure Collect_Interface_Components
374 (Tagged_Type : Entity_Id;
375 Components_List : out Elist_Id);
376 -- Ada 2005 (AI-251): Collect all the tag components associated with the
377 -- secondary dispatch tables of a tagged type.
378
379 procedure Collect_Interfaces_Info
380 (T : Entity_Id;
381 Ifaces_List : out Elist_Id;
382 Components_List : out Elist_Id;
383 Tags_List : out Elist_Id);
384 -- Ada 2005 (AI-251): Collect all the interfaces associated with T plus
385 -- the record component and tag associated with each of these interfaces.
386 -- On exit Ifaces_List, Components_List and Tags_List have the same number
387 -- of elements, and elements at the same position on these tables provide
388 -- information on the same interface type.
389
390 procedure Collect_Parents
391 (T : Entity_Id;
392 List : out Elist_Id;
393 Use_Full_View : Boolean := True);
394 -- Collect all the parents of Typ. Use_Full_View is used to collect them
395 -- using the full-view of private parents (if available).
396
397 function Collect_Primitive_Operations (T : Entity_Id) return Elist_Id;
398 -- Called upon type derivation and extension. We scan the declarative part
399 -- in which the type appears, and collect subprograms that have one
400 -- subsidiary subtype of the type. These subprograms can only appear after
401 -- the type itself.
402
403 function Compile_Time_Constraint_Error
404 (N : Node_Id;
405 Msg : String;
406 Ent : Entity_Id := Empty;
407 Loc : Source_Ptr := No_Location;
408 Warn : Boolean := False) return Node_Id;
409 -- This is similar to Apply_Compile_Time_Constraint_Error in that it
410 -- generates a warning (or error) message in the same manner, but it does
411 -- not replace any nodes. For convenience, the function always returns its
412 -- first argument. The message is a warning if the message ends with ?, or
413 -- we are operating in Ada 83 mode, or the Warn parameter is set to True.
414
415 procedure Conditional_Delay (New_Ent, Old_Ent : Entity_Id);
416 -- Sets the Has_Delayed_Freeze flag of New if the Delayed_Freeze flag of
417 -- Old is set and Old has no yet been Frozen (i.e. Is_Frozen is false).
418
419 function Contains_Refined_State (Prag : Node_Id) return Boolean;
420 -- Determine whether pragma Prag contains a reference to the entity of an
421 -- abstract state with a visible refinement. Prag must denote one of the
422 -- following pragmas:
423 -- Depends
424 -- Global
425
426 function Copy_Component_List
427 (R_Typ : Entity_Id;
428 Loc : Source_Ptr) return List_Id;
429 -- Copy components from record type R_Typ that come from source. Used to
430 -- create a new compatible record type. Loc is the source location assigned
431 -- to the created nodes.
432
433 function Copy_Parameter_List (Subp_Id : Entity_Id) return List_Id;
434 -- Utility to create a parameter profile for a new subprogram spec, when
435 -- the subprogram has a body that acts as spec. This is done for some cases
436 -- of inlining, and for private protected ops. Also used to create bodies
437 -- for stubbed subprograms.
438
439 function Copy_Subprogram_Spec (Spec : Node_Id) return Node_Id;
440 -- Replicate a function or a procedure specification denoted by Spec. The
441 -- resulting tree is an exact duplicate of the original tree. New entities
442 -- are created for the unit name and the formal parameters.
443
444 function Corresponding_Generic_Type (T : Entity_Id) return Entity_Id;
445 -- If a type is a generic actual type, return the corresponding formal in
446 -- the generic parent unit. There is no direct link in the tree for this
447 -- attribute, except in the case of formal private and derived types.
448 -- Possible optimization???
449
450 function Current_Entity (N : Node_Id) return Entity_Id;
451 pragma Inline (Current_Entity);
452 -- Find the currently visible definition for a given identifier, that is to
453 -- say the first entry in the visibility chain for the Chars of N.
454
455 function Current_Entity_In_Scope (N : Node_Id) return Entity_Id;
456 -- Find whether there is a previous definition for identifier N in the
457 -- current scope. Because declarations for a scope are not necessarily
458 -- contiguous (e.g. for packages) the first entry on the visibility chain
459 -- for N is not necessarily in the current scope.
460
461 function Current_Scope return Entity_Id;
462 -- Get entity representing current scope
463
464 function Current_Scope_No_Loops return Entity_Id;
465 -- Return the current scope ignoring internally generated loops
466
467 function Current_Subprogram return Entity_Id;
468 -- Returns current enclosing subprogram. If Current_Scope is a subprogram,
469 -- then that is what is returned, otherwise the Enclosing_Subprogram of the
470 -- Current_Scope is returned. The returned value is Empty if this is called
471 -- from a library package which is not within any subprogram.
472
473 function Deepest_Type_Access_Level (Typ : Entity_Id) return Uint;
474 -- Same as Type_Access_Level, except that if the type is the type of an Ada
475 -- 2012 stand-alone object of an anonymous access type, then return the
476 -- static accesssibility level of the object. In that case, the dynamic
477 -- accessibility level of the object may take on values in a range. The low
478 -- bound of that range is returned by Type_Access_Level; this function
479 -- yields the high bound of that range. Also differs from Type_Access_Level
480 -- in the case of a descendant of a generic formal type (returns Int'Last
481 -- instead of 0).
482
483 function Defining_Entity
484 (N : Node_Id;
485 Empty_On_Errors : Boolean := False) return Entity_Id;
486 -- Given a declaration N, returns the associated defining entity. If the
487 -- declaration has a specification, the entity is obtained from the
488 -- specification. If the declaration has a defining unit name, then the
489 -- defining entity is obtained from the defining unit name ignoring any
490 -- child unit prefixes.
491 --
492 -- Iterator loops also have a defining entity, which holds the list of
493 -- local entities declared during loop expansion. These entities need
494 -- debugging information, generated through Qualify_Entity_Names, and
495 -- the loop declaration must be placed in the table Name_Qualify_Units.
496 --
497 -- Set flag Empty_On_Error to change the behavior of this routine as
498 -- follows:
499 --
500 -- * True - A declaration that lacks a defining entity returns Empty.
501 -- A node that does not allow for a defining entity returns Empty.
502 --
503 -- * False - A declaration that lacks a defining entity is given a new
504 -- internally generated entity which is subsequently returned. A node
505 -- that does not allow for a defining entity raises Program_Error.
506 --
507 -- The former semantics is appropriate for the back end; the latter
508 -- semantics is appropriate for the front end.
509
510 function Denotes_Discriminant
511 (N : Node_Id;
512 Check_Concurrent : Boolean := False) return Boolean;
513 -- Returns True if node N is an Entity_Name node for a discriminant. If the
514 -- flag Check_Concurrent is true, function also returns true when N denotes
515 -- the discriminal of the discriminant of a concurrent type. This is needed
516 -- to disable some optimizations on private components of protected types,
517 -- and constraint checks on entry families constrained by discriminants.
518
519 function Denotes_Same_Object (A1, A2 : Node_Id) return Boolean;
520 -- Detect suspicious overlapping between actuals in a call, when both are
521 -- writable (RM 2012 6.4.1(6.4/3))
522
523 function Denotes_Same_Prefix (A1, A2 : Node_Id) return Boolean;
524 -- Functions to detect suspicious overlapping between actuals in a call,
525 -- when one of them is writable. The predicates are those proposed in
526 -- AI05-0144, to detect dangerous order dependence in complex calls.
527 -- I would add a parameter Warn which enables more extensive testing of
528 -- cases as we find appropriate when we are only warning ??? Or perhaps
529 -- return an indication of (Error, Warn, OK) ???
530
531 function Denotes_Variable (N : Node_Id) return Boolean;
532 -- Returns True if node N denotes a single variable without parentheses
533
534 function Depends_On_Discriminant (N : Node_Id) return Boolean;
535 -- Returns True if N denotes a discriminant or if N is a range, a subtype
536 -- indication or a scalar subtype where one of the bounds is a
537 -- discriminant.
538
539 function Designate_Same_Unit
540 (Name1 : Node_Id;
541 Name2 : Node_Id) return Boolean;
542 -- Returns True if Name1 and Name2 designate the same unit name; each of
543 -- these names is supposed to be a selected component name, an expanded
544 -- name, a defining program unit name or an identifier.
545
546 function Dynamic_Accessibility_Level (Expr : Node_Id) return Node_Id;
547 -- Expr should be an expression of an access type. Builds an integer
548 -- literal except in cases involving anonymous access types where
549 -- accessibility levels are tracked at runtime (access parameters and Ada
550 -- 2012 stand-alone objects).
551
552 function Effective_Extra_Accessibility (Id : Entity_Id) return Entity_Id;
553 -- Same as Einfo.Extra_Accessibility except thtat object renames
554 -- are looked through.
555
556 function Effective_Reads_Enabled (Id : Entity_Id) return Boolean;
557 -- Given the entity of an abstract state or a variable, determine whether
558 -- Id is subject to external property Effective_Reads and if it is, the
559 -- related expression evaluates to True.
560
561 function Effective_Writes_Enabled (Id : Entity_Id) return Boolean;
562 -- Given the entity of an abstract state or a variable, determine whether
563 -- Id is subject to external property Effective_Writes and if it is, the
564 -- related expression evaluates to True.
565
566 function Enclosing_Comp_Unit_Node (N : Node_Id) return Node_Id;
567 -- Returns the enclosing N_Compilation_Unit node that is the root of a
568 -- subtree containing N.
569
570 function Enclosing_CPP_Parent (Typ : Entity_Id) return Entity_Id;
571 -- Returns the closest ancestor of Typ that is a CPP type.
572
573 function Enclosing_Declaration (N : Node_Id) return Node_Id;
574 -- Returns the declaration node enclosing N (including possibly N itself),
575 -- if any, or Empty otherwise.
576
577 function Enclosing_Generic_Body
578 (N : Node_Id) return Node_Id;
579 -- Returns the Node_Id associated with the innermost enclosing generic
580 -- body, if any. If none, then returns Empty.
581
582 function Enclosing_Generic_Unit
583 (N : Node_Id) return Node_Id;
584 -- Returns the Node_Id associated with the innermost enclosing generic
585 -- unit, if any. If none, then returns Empty.
586
587 function Enclosing_Lib_Unit_Entity
588 (E : Entity_Id := Current_Scope) return Entity_Id;
589 -- Returns the entity of enclosing library unit node which is the root of
590 -- the current scope (which must not be Standard_Standard, and the caller
591 -- is responsible for ensuring this condition) or other specified entity.
592
593 function Enclosing_Lib_Unit_Node (N : Node_Id) return Node_Id;
594 -- Returns the N_Compilation_Unit node of the library unit that is directly
595 -- or indirectly (through a subunit) at the root of a subtree containing
596 -- N. This may be either the same as Enclosing_Comp_Unit_Node, or if
597 -- Enclosing_Comp_Unit_Node returns a subunit, then the corresponding
598 -- library unit. If no such item is found, returns Empty.
599
600 function Enclosing_Package (E : Entity_Id) return Entity_Id;
601 -- Utility function to return the Ada entity of the package enclosing
602 -- the entity E, if any. Returns Empty if no enclosing package.
603
604 function Enclosing_Package_Or_Subprogram (E : Entity_Id) return Entity_Id;
605 -- Returns the entity of the package or subprogram enclosing E, if any.
606 -- Returns Empty if no enclosing package or subprogram.
607
608 function Enclosing_Subprogram (E : Entity_Id) return Entity_Id;
609 -- Utility function to return the Ada entity of the subprogram enclosing
610 -- the entity E, if any. Returns Empty if no enclosing subprogram.
611
612 procedure Ensure_Freeze_Node (E : Entity_Id);
613 -- Make sure a freeze node is allocated for entity E. If necessary, build
614 -- and initialize a new freeze node and set Has_Delayed_Freeze True for E.
615
616 procedure Enter_Name (Def_Id : Entity_Id);
617 -- Insert new name in symbol table of current scope with check for
618 -- duplications (error message is issued if a conflict is found).
619 -- Note: Enter_Name is not used for overloadable entities, instead these
620 -- are entered using Sem_Ch6.Enter_Overloadable_Entity.
621
622 function Entity_Of (N : Node_Id) return Entity_Id;
623 -- Return the entity of N or Empty. If N is a renaming, return the entity
624 -- of the root renamed object.
625
626 procedure Explain_Limited_Type (T : Entity_Id; N : Node_Id);
627 -- This procedure is called after issuing a message complaining about an
628 -- inappropriate use of limited type T. If useful, it adds additional
629 -- continuation lines to the message explaining why type T is limited.
630 -- Messages are placed at node N.
631
632 type Extensions_Visible_Mode is
633 (Extensions_Visible_None,
634 -- Extensions_Visible does not yield a mode when SPARK_Mode is off. This
635 -- value acts as a default in a non-SPARK compilation.
636
637 Extensions_Visible_False,
638 -- A value of "False" signifies that Extensions_Visible is either
639 -- missing or the pragma is present and the value of its Boolean
640 -- expression is False.
641
642 Extensions_Visible_True);
643 -- A value of "True" signifies that Extensions_Visible is present and
644 -- the value of its Boolean expression is True.
645
646 function Extensions_Visible_Status
647 (Id : Entity_Id) return Extensions_Visible_Mode;
648 -- Given the entity of a subprogram or formal parameter subject to pragma
649 -- Extensions_Visible, return the Boolean value denoted by the expression
650 -- of the pragma.
651
652 procedure Find_Actual
653 (N : Node_Id;
654 Formal : out Entity_Id;
655 Call : out Node_Id);
656 -- Determines if the node N is an actual parameter of a function or a
657 -- procedure call. If so, then Formal points to the entity for the formal
658 -- (Ekind is E_In_Parameter, E_Out_Parameter, or E_In_Out_Parameter) and
659 -- Call is set to the node for the corresponding call. If the node N is not
660 -- an actual parameter then Formal and Call are set to Empty.
661
662 function Find_Specific_Type (CW : Entity_Id) return Entity_Id;
663 -- Find specific type of a class-wide type, and handle the case of an
664 -- incomplete type coming either from a limited_with clause or from an
665 -- incomplete type declaration. If resulting type is private return its
666 -- full view.
667
668 function Find_Body_Discriminal
669 (Spec_Discriminant : Entity_Id) return Entity_Id;
670 -- Given a discriminant of the record type that implements a task or
671 -- protected type, return the discriminal of the corresponding discriminant
672 -- of the actual concurrent type.
673
674 function Find_Corresponding_Discriminant
675 (Id : Node_Id;
676 Typ : Entity_Id) return Entity_Id;
677 -- Because discriminants may have different names in a generic unit and in
678 -- an instance, they are resolved positionally when possible. A reference
679 -- to a discriminant carries the discriminant that it denotes when it is
680 -- analyzed. Subsequent uses of this id on a different type denotes the
681 -- discriminant at the same position in this new type.
682
683 function Find_Enclosing_Iterator_Loop (Id : Entity_Id) return Entity_Id;
684 -- Given an arbitrary entity, try to find the nearest enclosing iterator
685 -- loop. If such a loop is found, return the entity of its identifier (the
686 -- E_Loop scope), otherwise return Empty.
687
688 function Find_Loop_In_Conditional_Block (N : Node_Id) return Node_Id;
689 -- Find the nested loop statement in a conditional block. Loops subject to
690 -- attribute 'Loop_Entry are transformed into blocks. Parts of the original
691 -- loop are nested within the block.
692
693 procedure Find_Overlaid_Entity
694 (N : Node_Id;
695 Ent : out Entity_Id;
696 Off : out Boolean);
697 -- The node N should be an address representation clause. Determines if
698 -- the target expression is the address of an entity with an optional
699 -- offset. If so, set Ent to the entity and, if there is an offset, set
700 -- Off to True, otherwise to False. If N is not an address representation
701 -- clause, or if it is not possible to determine that the address is of
702 -- this form, then set Ent to Empty.
703
704 function Find_Parameter_Type (Param : Node_Id) return Entity_Id;
705 -- Return the type of formal parameter Param as determined by its
706 -- specification.
707
708 -- The following type describes the placement of an arbitrary entity with
709 -- respect to SPARK visible / hidden state space.
710
711 type State_Space_Kind is
712 (Not_In_Package,
713 -- An entity is not in the visible, private or body state space when
714 -- the immediate enclosing construct is not a package.
715
716 Visible_State_Space,
717 -- An entity is in the visible state space when it appears immediately
718 -- within the visible declarations of a package or when it appears in
719 -- the visible state space of a nested package which in turn is declared
720 -- in the visible declarations of an enclosing package:
721
722 -- package Pack is
723 -- Visible_Variable : ...
724 -- package Nested
725 -- with Abstract_State => Visible_State
726 -- is
727 -- Visible_Nested_Variable : ...
728 -- end Nested;
729 -- end Pack;
730
731 -- Entities associated with a package instantiation inherit the state
732 -- space from the instance placement:
733
734 -- generic
735 -- package Gen is
736 -- Generic_Variable : ...
737 -- end Gen;
738
739 -- with Gen;
740 -- package Pack is
741 -- package Inst is new Gen;
742 -- -- Generic_Variable is in the visible state space of Pack
743 -- end Pack;
744
745 Private_State_Space,
746 -- An entity is in the private state space when it appears immediately
747 -- within the private declarations of a package or when it appears in
748 -- the visible state space of a nested package which in turn is declared
749 -- in the private declarations of an enclosing package:
750
751 -- package Pack is
752 -- private
753 -- Private_Variable : ...
754 -- package Nested
755 -- with Abstract_State => Private_State
756 -- is
757 -- Private_Nested_Variable : ...
758 -- end Nested;
759 -- end Pack;
760
761 -- The same placement principle applies to package instantiations
762
763 Body_State_Space);
764 -- An entity is in the body state space when it appears immediately
765 -- within the declarations of a package body or when it appears in the
766 -- visible state space of a nested package which in turn is declared in
767 -- the declarations of an enclosing package body:
768
769 -- package body Pack is
770 -- Body_Variable : ...
771 -- package Nested
772 -- with Abstract_State => Body_State
773 -- is
774 -- Body_Nested_Variable : ...
775 -- end Nested;
776 -- end Pack;
777
778 -- The same placement principle applies to package instantiations
779
780 procedure Find_Placement_In_State_Space
781 (Item_Id : Entity_Id;
782 Placement : out State_Space_Kind;
783 Pack_Id : out Entity_Id);
784 -- Determine the state space placement of an item. Item_Id denotes the
785 -- entity of an abstract state, object or package instantiation. Placement
786 -- captures the precise placement of the item in the enclosing state space.
787 -- If the state space is that of a package, Pack_Id denotes its entity,
788 -- otherwise Pack_Id is Empty.
789
790 function Find_Static_Alternative (N : Node_Id) return Node_Id;
791 -- N is a case statement whose expression is a compile-time value.
792 -- Determine the alternative chosen, so that the code of non-selected
793 -- alternatives, and the warnings that may apply to them, are removed.
794
795 function First_Actual (Node : Node_Id) return Node_Id;
796 -- Node is an N_Function_Call, N_Procedure_Call_Statement or
797 -- N_Entry_Call_Statement node. The result returned is the first actual
798 -- parameter in declaration order (not the order of parameters as they
799 -- appeared in the source, which can be quite different as a result of the
800 -- use of named parameters). Empty is returned for a call with no
801 -- parameters. The procedure for iterating through the actuals in
802 -- declaration order is to use this function to find the first actual, and
803 -- then use Next_Actual to obtain the next actual in declaration order.
804 -- Note that the value returned is always the expression (not the
805 -- N_Parameter_Association nodes, even if named association is used).
806
807 function Fix_Msg (Id : Entity_Id; Msg : String) return String;
808 -- Replace all occurrences of a particular word in string Msg depending on
809 -- the Ekind of Id as follows:
810 -- * Replace "subprogram" with
811 -- - "entry" when Id is an entry [family]
812 -- - "task type" when Id is a single task object, task type or task
813 -- body.
814 -- * Replace "protected" with
815 -- - "task" when Id is a single task object, task type or task body
816 -- All other non-matching words remain as is
817
818 procedure Gather_Components
819 (Typ : Entity_Id;
820 Comp_List : Node_Id;
821 Governed_By : List_Id;
822 Into : Elist_Id;
823 Report_Errors : out Boolean);
824 -- The purpose of this procedure is to gather the valid components in a
825 -- record type according to the values of its discriminants, in order to
826 -- validate the components of a record aggregate.
827 --
828 -- Typ is the type of the aggregate when its constrained discriminants
829 -- need to be collected, otherwise it is Empty.
830 --
831 -- Comp_List is an N_Component_List node.
832 --
833 -- Governed_By is a list of N_Component_Association nodes, where each
834 -- choice list contains the name of a discriminant and the expression
835 -- field gives its value. The values of the discriminants governing
836 -- the (possibly nested) variant parts in Comp_List are found in this
837 -- Component_Association List.
838 --
839 -- Into is the list where the valid components are appended. Note that
840 -- Into need not be an Empty list. If it's not, components are attached
841 -- to its tail.
842 --
843 -- Report_Errors is set to True if the values of the discriminants are
844 -- non-static.
845 --
846 -- This procedure is also used when building a record subtype. If the
847 -- discriminant constraint of the subtype is static, the components of the
848 -- subtype are only those of the variants selected by the values of the
849 -- discriminants. Otherwise all components of the parent must be included
850 -- in the subtype for semantic analysis.
851
852 function Get_Actual_Subtype (N : Node_Id) return Entity_Id;
853 -- Given a node for an expression, obtain the actual subtype of the
854 -- expression. In the case of a parameter where the formal is an
855 -- unconstrained array or discriminated type, this will be the previously
856 -- constructed subtype of the actual. Note that this is not quite the
857 -- "Actual Subtype" of the RM, since it is always a constrained type, i.e.
858 -- it is the subtype of the value of the actual. The actual subtype is also
859 -- returned in other cases where it has already been constructed for an
860 -- object. Otherwise the expression type is returned unchanged, except for
861 -- the case of an unconstrained array type, where an actual subtype is
862 -- created, using Insert_Actions if necessary to insert any associated
863 -- actions.
864
865 function Get_Actual_Subtype_If_Available (N : Node_Id) return Entity_Id;
866 -- This is like Get_Actual_Subtype, except that it never constructs an
867 -- actual subtype. If an actual subtype is already available, i.e. the
868 -- Actual_Subtype field of the corresponding entity is set, then it is
869 -- returned. Otherwise the Etype of the node is returned.
870
871 function Get_Body_From_Stub (N : Node_Id) return Node_Id;
872 -- Return the body node for a stub
873
874 function Get_Cursor_Type
875 (Aspect : Node_Id;
876 Typ : Entity_Id) return Entity_Id;
877 -- Find Cursor type in scope of type Typ with Iterable aspect, by locating
878 -- primitive operation First. For use in resolving the other primitive
879 -- operations of an Iterable type and expanding loops and quantified
880 -- expressions over formal containers.
881
882 function Get_Cursor_Type (Typ : Entity_Id) return Entity_Id;
883 -- Find Cursor type in scope of type Typ with Iterable aspect, by locating
884 -- primitive operation First. For use after resolving the primitive
885 -- operations of an Iterable type.
886
887 function Get_Default_External_Name (E : Node_Or_Entity_Id) return Node_Id;
888 -- This is used to construct the string literal node representing a
889 -- default external name, i.e. one that is constructed from the name of an
890 -- entity, or (in the case of extended DEC import/export pragmas, an
891 -- identifier provided as the external name. Letters in the name are
892 -- according to the setting of Opt.External_Name_Default_Casing.
893
894 function Get_Enclosing_Object (N : Node_Id) return Entity_Id;
895 -- If expression N references a part of an object, return this object.
896 -- Otherwise return Empty. Expression N should have been resolved already.
897
898 function Get_Generic_Entity (N : Node_Id) return Entity_Id;
899 -- Returns the true generic entity in an instantiation. If the name in the
900 -- instantiation is a renaming, the function returns the renamed generic.
901
902 function Get_Incomplete_View_Of_Ancestor (E : Entity_Id) return Entity_Id;
903 -- Implements the notion introduced ever-so briefly in RM 7.3.1 (5.2/3):
904 -- in a child unit a derived type is within the derivation class of an
905 -- ancestor declared in a parent unit, even if there is an intermediate
906 -- derivation that does not see the full view of that ancestor.
907
908 procedure Get_Index_Bounds (N : Node_Id; L, H : out Node_Id);
909 -- This procedure assigns to L and H respectively the values of the low and
910 -- high bounds of node N, which must be a range, subtype indication, or the
911 -- name of a scalar subtype. The result in L, H may be set to Error if
912 -- there was an earlier error in the range.
913
914 function Get_Enum_Lit_From_Pos
915 (T : Entity_Id;
916 Pos : Uint;
917 Loc : Source_Ptr) return Node_Id;
918 -- This function returns an identifier denoting the E_Enumeration_Literal
919 -- entity for the specified value from the enumeration type or subtype T.
920 -- The second argument is the Pos value, which is assumed to be in range.
921 -- The third argument supplies a source location for constructed nodes
922 -- returned by this function.
923
924 function Get_Iterable_Type_Primitive
925 (Typ : Entity_Id;
926 Nam : Name_Id) return Entity_Id;
927 -- Retrieve one of the primitives First, Next, Has_Element, Element from
928 -- the value of the Iterable aspect of a formal type.
929
930 procedure Get_Library_Unit_Name_String (Decl_Node : Node_Id);
931 -- Retrieve the fully expanded name of the library unit declared by
932 -- Decl_Node into the name buffer.
933
934 function Get_Name_Entity_Id (Id : Name_Id) return Entity_Id;
935 pragma Inline (Get_Name_Entity_Id);
936 -- An entity value is associated with each name in the name table. The
937 -- Get_Name_Entity_Id function fetches the Entity_Id of this entity, which
938 -- is the innermost visible entity with the given name. See the body of
939 -- Sem_Ch8 for further details on handling of entity visibility.
940
941 function Get_Name_From_CTC_Pragma (N : Node_Id) return String_Id;
942 -- Return the Name component of Test_Case pragma N
943 -- Bad name now that this no longer applies to Contract_Case ???
944
945 function Get_Parent_Entity (Unit : Node_Id) return Entity_Id;
946 -- Get defining entity of parent unit of a child unit. In most cases this
947 -- is the defining entity of the unit, but for a child instance whose
948 -- parent needs a body for inlining, the instantiation node of the parent
949 -- has not yet been rewritten as a package declaration, and the entity has
950 -- to be retrieved from the Instance_Spec of the unit.
951
952 function Get_Pragma_Id (N : Node_Id) return Pragma_Id;
953 pragma Inline (Get_Pragma_Id);
954 -- Obtains the Pragma_Id from the Chars field of Pragma_Identifier (N)
955
956 function Get_Qualified_Name
957 (Id : Entity_Id;
958 Suffix : Entity_Id := Empty) return Name_Id;
959 -- Obtain the fully qualified form of entity Id. The format is:
960 -- scope_of_id-1__scope_of_id__chars_of_id__chars_of_suffix
961
962 function Get_Qualified_Name
963 (Nam : Name_Id;
964 Suffix : Name_Id := No_Name;
965 Scop : Entity_Id := Current_Scope) return Name_Id;
966 -- Obtain the fully qualified form of name Nam assuming it appears in scope
967 -- Scop. The format is:
968 -- scop-1__scop__nam__suffix
969
970 procedure Get_Reason_String (N : Node_Id);
971 -- Recursive routine to analyze reason argument for pragma Warnings. The
972 -- value of the reason argument is appended to the current string using
973 -- Store_String_Chars. The reason argument is expected to be a string
974 -- literal or concatenation of string literals. An error is given for
975 -- any other form.
976
977 function Get_Reference_Discriminant (Typ : Entity_Id) return Entity_Id;
978 -- If Typ has Implicit_Dereference, return discriminant specified in the
979 -- corresponding aspect.
980
981 function Get_Referenced_Object (N : Node_Id) return Node_Id;
982 -- Given a node, return the renamed object if the node represents a renamed
983 -- object, otherwise return the node unchanged. The node may represent an
984 -- arbitrary expression.
985
986 function Get_Renamed_Entity (E : Entity_Id) return Entity_Id;
987 -- Given an entity for an exception, package, subprogram or generic unit,
988 -- returns the ultimately renamed entity if this is a renaming. If this is
989 -- not a renamed entity, returns its argument. It is an error to call this
990 -- with any other kind of entity.
991
992 function Get_Return_Object (N : Node_Id) return Entity_Id;
993 -- Given an extended return statement, return the corresponding return
994 -- object, identified as the one for which Is_Return_Object = True.
995
996 function Get_Subprogram_Entity (Nod : Node_Id) return Entity_Id;
997 -- Nod is either a procedure call statement, or a function call, or an
998 -- accept statement node. This procedure finds the Entity_Id of the related
999 -- subprogram or entry and returns it, or if no subprogram can be found,
1000 -- returns Empty.
1001
1002 function Get_Task_Body_Procedure (E : Entity_Id) return Node_Id;
1003 pragma Inline (Get_Task_Body_Procedure);
1004 -- Given an entity for a task type or subtype, retrieves the
1005 -- Task_Body_Procedure field from the corresponding task type declaration.
1006
1007 function Get_User_Defined_Eq (E : Entity_Id) return Entity_Id;
1008 -- For a type entity, return the entity of the primitive equality function
1009 -- for the type if it exists, otherwise return Empty.
1010
1011 procedure Get_Views
1012 (Typ : Entity_Id;
1013 Priv_Typ : out Entity_Id;
1014 Full_Typ : out Entity_Id;
1015 Full_Base : out Entity_Id;
1016 CRec_Typ : out Entity_Id);
1017 -- Obtain the partial and full view of type Typ and in addition any extra
1018 -- types the full view may have. The return entities are as follows:
1019 --
1020 -- Priv_Typ - the partial view (a private type)
1021 -- Full_Typ - the full view
1022 -- Full_Base - the base type of the full view
1023 -- CRec_Typ - the corresponding record type of the full view
1024
1025 function Has_Access_Values (T : Entity_Id) return Boolean;
1026 -- Returns true if type or subtype T is an access type, or has a component
1027 -- (at any recursive level) that is an access type. This is a conservative
1028 -- predicate, if it is not known whether or not T contains access values
1029 -- (happens for generic formals in some cases), then False is returned.
1030 -- Note that tagged types return False. Even though the tag is implemented
1031 -- as an access type internally, this function tests only for access types
1032 -- known to the programmer. See also Has_Tagged_Component.
1033
1034 type Alignment_Result is (Known_Compatible, Unknown, Known_Incompatible);
1035 -- Result of Has_Compatible_Alignment test, description found below. Note
1036 -- that the values are arranged in increasing order of problematicness.
1037
1038 function Has_Compatible_Alignment
1039 (Obj : Entity_Id;
1040 Expr : Node_Id;
1041 Layout_Done : Boolean) return Alignment_Result;
1042 -- Obj is an object entity, and expr is a node for an object reference. If
1043 -- the alignment of the object referenced by Expr is known to be compatible
1044 -- with the alignment of Obj (i.e. is larger or the same), then the result
1045 -- is Known_Compatible. If the alignment of the object referenced by Expr
1046 -- is known to be less than the alignment of Obj, then Known_Incompatible
1047 -- is returned. If neither condition can be reliably established at compile
1048 -- time, then Unknown is returned. If Layout_Done is True, the function can
1049 -- assume that the information on size and alignment of types and objects
1050 -- is present in the tree. This is used to determine if alignment checks
1051 -- are required for address clauses (Layout_Done is False in this case) as
1052 -- well as to issue appropriate warnings for them in the post compilation
1053 -- phase (Layout_Done is True in this case).
1054 --
1055 -- Note: Known_Incompatible does not mean that at run time the alignment
1056 -- of Expr is known to be wrong for Obj, just that it can be determined
1057 -- that alignments have been explicitly or implicitly specified which are
1058 -- incompatible (whereas Unknown means that even this is not known). The
1059 -- appropriate reaction of a caller to Known_Incompatible is to treat it as
1060 -- Unknown, but issue a warning that there may be an alignment error.
1061
1062 function Has_Declarations (N : Node_Id) return Boolean;
1063 -- Determines if the node can have declarations
1064
1065 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean;
1066 -- Simple predicate to test for defaulted discriminants
1067
1068 function Has_Denormals (E : Entity_Id) return Boolean;
1069 -- Determines if the floating-point type E supports denormal numbers.
1070 -- Returns False if E is not a floating-point type.
1071
1072 function Has_Discriminant_Dependent_Constraint
1073 (Comp : Entity_Id) return Boolean;
1074 -- Returns True if and only if Comp has a constrained subtype that depends
1075 -- on a discriminant.
1076
1077 function Has_Effectively_Volatile_Profile
1078 (Subp_Id : Entity_Id) return Boolean;
1079 -- Determine whether subprogram Subp_Id has an effectively volatile formal
1080 -- parameter or returns an effectively volatile value.
1081
1082 function Has_Full_Default_Initialization (Typ : Entity_Id) return Boolean;
1083 -- Determine whether type Typ defines "full default initialization" as
1084 -- specified by SPARK RM 3.1. To qualify as such, the type must be
1085 -- * A scalar type with specified Default_Value
1086 -- * An array-of-scalar type with specified Default_Component_Value
1087 -- * An array type whose element type defines full default initialization
1088 -- * A protected type, record type or type extension whose components
1089 -- either include a default expression or have a type which defines
1090 -- full default initialization. In the case of type extensions, the
1091 -- parent type defines full default initialization.
1092 -- * A task type
1093 -- * A private type whose Default_Initial_Condition is non-null
1094
1095 function Has_Infinities (E : Entity_Id) return Boolean;
1096 -- Determines if the range of the floating-point type E includes
1097 -- infinities. Returns False if E is not a floating-point type.
1098
1099 function Has_Interfaces
1100 (T : Entity_Id;
1101 Use_Full_View : Boolean := True) return Boolean;
1102 -- Where T is a concurrent type or a record type, returns true if T covers
1103 -- any abstract interface types. In case of private types the argument
1104 -- Use_Full_View controls if the check is done using its full view (if
1105 -- available).
1106
1107 function Has_No_Obvious_Side_Effects (N : Node_Id) return Boolean;
1108 -- This is a simple minded function for determining whether an expression
1109 -- has no obvious side effects. It is used only for determining whether
1110 -- warnings are needed in certain situations, and is not guaranteed to
1111 -- be accurate in either direction. Exceptions may mean an expression
1112 -- does in fact have side effects, but this may be ignored and True is
1113 -- returned, or a complex expression may in fact be side effect free
1114 -- but we don't recognize it here and return False. The Side_Effect_Free
1115 -- routine in Remove_Side_Effects is much more extensive and perhaps could
1116 -- be shared, so that this routine would be more accurate.
1117
1118 function Has_Non_Null_Refinement (Id : Entity_Id) return Boolean;
1119 -- Determine whether abstract state Id has at least one nonnull constituent
1120 -- as expressed in pragma Refined_State. This function does not take into
1121 -- account the visible refinement region of abstract state Id.
1122
1123 function Has_Null_Body (Proc_Id : Entity_Id) return Boolean;
1124 -- Determine whether the body of procedure Proc_Id contains a sole
1125 -- null statement, possibly followed by an optional return. Used to
1126 -- optimize useless calls to assertion checks.
1127
1128 function Has_Null_Exclusion (N : Node_Id) return Boolean;
1129 -- Determine whether node N has a null exclusion
1130
1131 function Has_Null_Refinement (Id : Entity_Id) return Boolean;
1132 -- Determine whether abstract state Id has a null refinement as expressed
1133 -- in pragma Refined_State. This function does not take into account the
1134 -- visible refinement region of abstract state Id.
1135
1136 function Has_Overriding_Initialize (T : Entity_Id) return Boolean;
1137 -- Predicate to determine whether a controlled type has a user-defined
1138 -- Initialize primitive (and, in Ada 2012, whether that primitive is
1139 -- non-null), which causes the type to not have preelaborable
1140 -- initialization.
1141
1142 function Has_Preelaborable_Initialization (E : Entity_Id) return Boolean;
1143 -- Return True iff type E has preelaborable initialization as defined in
1144 -- Ada 2005 (see AI-161 for details of the definition of this attribute).
1145
1146 function Has_Private_Component (Type_Id : Entity_Id) return Boolean;
1147 -- Check if a type has a (sub)component of a private type that has not
1148 -- yet received a full declaration.
1149
1150 function Has_Signed_Zeros (E : Entity_Id) return Boolean;
1151 -- Determines if the floating-point type E supports signed zeros.
1152 -- Returns False if E is not a floating-point type.
1153
1154 function Has_Significant_Contract (Subp_Id : Entity_Id) return Boolean;
1155 -- Determine whether subprogram [body] Subp_Id has a significant contract.
1156 -- All subprograms have a N_Contract node, but this does not mean that the
1157 -- contract is useful.
1158
1159 function Has_Static_Array_Bounds (Typ : Node_Id) return Boolean;
1160 -- Return whether an array type has static bounds
1161
1162 function Has_Stream (T : Entity_Id) return Boolean;
1163 -- Tests if type T is derived from Ada.Streams.Root_Stream_Type, or in the
1164 -- case of a composite type, has a component for which this predicate is
1165 -- True, and if so returns True. Otherwise a result of False means that
1166 -- there is no Stream type in sight. For a private type, the test is
1167 -- applied to the underlying type (or returns False if there is no
1168 -- underlying type).
1169
1170 function Has_Suffix (E : Entity_Id; Suffix : Character) return Boolean;
1171 -- Returns true if the last character of E is Suffix. Used in Assertions.
1172
1173 function Has_Tagged_Component (Typ : Entity_Id) return Boolean;
1174 -- Returns True if Typ is a composite type (array or record) which is
1175 -- either itself a tagged type, or has a component (recursively) which is
1176 -- a tagged type. Returns False for non-composite type, or if no tagged
1177 -- component is present. This function is used to check if "=" has to be
1178 -- expanded into a bunch component comparisons.
1179
1180 function Has_Undefined_Reference (Expr : Node_Id) return Boolean;
1181 -- Given arbitrary expression Expr, determine whether it contains at
1182 -- least one name whose entity is Any_Id.
1183
1184 function Has_Volatile_Component (Typ : Entity_Id) return Boolean;
1185 -- Given arbitrary type Typ, determine whether it contains at least one
1186 -- volatile component.
1187
1188 function Implementation_Kind (Subp : Entity_Id) return Name_Id;
1189 -- Subp is a subprogram marked with pragma Implemented. Return the specific
1190 -- implementation requirement which the pragma imposes. The return value is
1191 -- either Name_By_Any, Name_By_Entry or Name_By_Protected_Procedure.
1192
1193 function Implements_Interface
1194 (Typ_Ent : Entity_Id;
1195 Iface_Ent : Entity_Id;
1196 Exclude_Parents : Boolean := False) return Boolean;
1197 -- Returns true if the Typ_Ent implements interface Iface_Ent
1198
1199 function In_Assertion_Expression_Pragma (N : Node_Id) return Boolean;
1200 -- Returns True if node N appears within a pragma that acts as an assertion
1201 -- expression. See Sem_Prag for the list of qualifying pragmas.
1202
1203 function In_Instance return Boolean;
1204 -- Returns True if the current scope is within a generic instance
1205
1206 function In_Instance_Body return Boolean;
1207 -- Returns True if current scope is within the body of an instance, where
1208 -- several semantic checks (e.g. accessibility checks) are relaxed.
1209
1210 function In_Instance_Not_Visible return Boolean;
1211 -- Returns True if current scope is with the private part or the body of
1212 -- an instance. Other semantic checks are suppressed in this context.
1213
1214 function In_Instance_Visible_Part return Boolean;
1215 -- Returns True if current scope is within the visible part of a package
1216 -- instance, where several additional semantic checks apply.
1217
1218 function In_Package_Body return Boolean;
1219 -- Returns True if current scope is within a package body
1220
1221 function In_Parameter_Specification (N : Node_Id) return Boolean;
1222 -- Returns True if node N belongs to a parameter specification
1223
1224 function In_Pragma_Expression (N : Node_Id; Nam : Name_Id) return Boolean;
1225 -- Returns true if the expression N occurs within a pragma with name Nam
1226
1227 function In_Pre_Post_Condition (N : Node_Id) return Boolean;
1228 -- Returns True if node N appears within a pre/postcondition pragma. Note
1229 -- the pragma Check equivalents are NOT considered.
1230
1231 function In_Reverse_Storage_Order_Object (N : Node_Id) return Boolean;
1232 -- Returns True if N denotes a component or subcomponent in a record or
1233 -- array that has Reverse_Storage_Order.
1234
1235 function In_Subprogram_Or_Concurrent_Unit return Boolean;
1236 -- Determines if the current scope is within a subprogram compilation unit
1237 -- (inside a subprogram declaration, subprogram body, or generic subprogram
1238 -- declaration) or within a task or protected body. The test is for
1239 -- appearing anywhere within such a construct (that is it does not need
1240 -- to be directly within).
1241
1242 function In_Visible_Part (Scope_Id : Entity_Id) return Boolean;
1243 -- Determine whether a declaration occurs within the visible part of a
1244 -- package specification. The package must be on the scope stack, and the
1245 -- corresponding private part must not.
1246
1247 function Incomplete_Or_Partial_View (Id : Entity_Id) return Entity_Id;
1248 -- Given the entity of a constant or a type, retrieve the incomplete or
1249 -- partial view of the same entity. Note that Id may not have a partial
1250 -- view in which case the function returns Empty.
1251
1252 function Indexed_Component_Bit_Offset (N : Node_Id) return Uint;
1253 -- Given an N_Indexed_Component node, return the first bit position of the
1254 -- component if it is known at compile time. A value of No_Uint means that
1255 -- either the value is not yet known before back-end processing or it is
1256 -- not known at compile time after back-end processing.
1257
1258 procedure Inherit_Default_Init_Cond_Procedure (Typ : Entity_Id);
1259 -- Inherit the default initial condition procedure from the parent type of
1260 -- derived type Typ.
1261
1262 procedure Inherit_Rep_Item_Chain (Typ : Entity_Id; From_Typ : Entity_Id);
1263 -- Inherit the rep item chain of type From_Typ without clobbering any
1264 -- existing rep items on Typ's chain. Typ is the destination type.
1265
1266 procedure Insert_Explicit_Dereference (N : Node_Id);
1267 -- In a context that requires a composite or subprogram type and where a
1268 -- prefix is an access type, rewrite the access type node N (which is the
1269 -- prefix, e.g. of an indexed component) as an explicit dereference.
1270
1271 procedure Inspect_Deferred_Constant_Completion (Decls : List_Id);
1272 -- Examine all deferred constants in the declaration list Decls and check
1273 -- whether they have been completed by a full constant declaration or an
1274 -- Import pragma. Emit the error message if that is not the case.
1275
1276 procedure Install_Generic_Formals (Subp_Id : Entity_Id);
1277 -- Install both the generic formal parameters and the formal parameters of
1278 -- generic subprogram Subp_Id into visibility.
1279
1280 function Is_Actual_Out_Parameter (N : Node_Id) return Boolean;
1281 -- Determines if N is an actual parameter of out mode in a subprogram call
1282
1283 function Is_Actual_Parameter (N : Node_Id) return Boolean;
1284 -- Determines if N is an actual parameter in a subprogram call
1285
1286 function Is_Actual_Tagged_Parameter (N : Node_Id) return Boolean;
1287 -- Determines if N is an actual parameter of a formal of tagged type in a
1288 -- subprogram call.
1289
1290 function Is_Aliased_View (Obj : Node_Id) return Boolean;
1291 -- Determine if Obj is an aliased view, i.e. the name of an object to which
1292 -- 'Access or 'Unchecked_Access can apply. Note that this routine uses the
1293 -- rules of the language, it does not take into account the restriction
1294 -- No_Implicit_Aliasing, so it can return True if the restriction is active
1295 -- and Obj violates the restriction. The caller is responsible for calling
1296 -- Restrict.Check_No_Implicit_Aliasing if True is returned, but there is a
1297 -- requirement for obeying the restriction in the call context.
1298
1299 function Is_Ancestor_Package
1300 (E1 : Entity_Id;
1301 E2 : Entity_Id) return Boolean;
1302 -- Determine whether package E1 is an ancestor of E2
1303
1304 function Is_Atomic_Object (N : Node_Id) return Boolean;
1305 -- Determines if the given node denotes an atomic object in the sense of
1306 -- the legality checks described in RM C.6(12).
1307
1308 function Is_Atomic_Or_VFA_Object (N : Node_Id) return Boolean;
1309 -- Determines if the given node is an atomic object (Is_Atomic_Object true)
1310 -- or else is an object for which VFA is present.
1311
1312 function Is_Attribute_Result (N : Node_Id) return Boolean;
1313 -- Determine whether node N denotes attribute 'Result
1314
1315 function Is_Attribute_Update (N : Node_Id) return Boolean;
1316 -- Determine whether node N denotes attribute 'Update
1317
1318 function Is_Body_Or_Package_Declaration (N : Node_Id) return Boolean;
1319 -- Determine whether node N denotes a body or a package declaration
1320
1321 function Is_Bounded_String (T : Entity_Id) return Boolean;
1322 -- True if T is a bounded string type. Used to make sure "=" composes
1323 -- properly for bounded string types.
1324
1325 function Is_Constant_Bound (Exp : Node_Id) return Boolean;
1326 -- Exp is the expression for an array bound. Determines whether the
1327 -- bound is a compile-time known value, or a constant entity, or an
1328 -- enumeration literal, or an expression composed of constant-bound
1329 -- subexpressions which are evaluated by means of standard operators.
1330
1331 function Is_Container_Element (Exp : Node_Id) return Boolean;
1332 -- This routine recognizes expressions that denote an element of one of
1333 -- the predefined containers, when the source only contains an indexing
1334 -- operation and an implicit dereference is inserted by the compiler.
1335 -- In the absence of this optimization, the indexing creates a temporary
1336 -- controlled cursor that sets the tampering bit of the container, and
1337 -- restricts the use of the convenient notation C (X) to contexts that
1338 -- do not check the tampering bit (e.g. C.Include (X, C (Y)). Exp is an
1339 -- explicit dereference. The transformation applies when it has the form
1340 -- F (X).Discr.all.
1341
1342 function Is_Contract_Annotation (Item : Node_Id) return Boolean;
1343 -- Determine whether aspect specification or pragma Item is a contract
1344 -- annotation.
1345
1346 function Is_Controlling_Limited_Procedure
1347 (Proc_Nam : Entity_Id) return Boolean;
1348 -- Ada 2005 (AI-345): Determine whether Proc_Nam is a primitive procedure
1349 -- of a limited interface with a controlling first parameter.
1350
1351 function Is_CPP_Constructor_Call (N : Node_Id) return Boolean;
1352 -- Returns True if N is a call to a CPP constructor
1353
1354 function Is_Child_Or_Sibling
1355 (Pack_1 : Entity_Id;
1356 Pack_2 : Entity_Id) return Boolean;
1357 -- Determine the following relations between two arbitrary packages:
1358 -- 1) One package is the parent of a child package
1359 -- 2) Both packages are siblings and share a common parent
1360
1361 function Is_Concurrent_Interface (T : Entity_Id) return Boolean;
1362 -- First determine whether type T is an interface and then check whether
1363 -- it is of protected, synchronized or task kind.
1364
1365 function Is_Current_Instance (N : Node_Id) return Boolean;
1366 -- Predicate is true if N legally denotes a type name within its own
1367 -- declaration. Prior to Ada 2012 this covered only synchronized type
1368 -- declarations. In Ada 2012 it also covers type and subtype declarations
1369 -- with aspects: Invariant, Predicate, and Default_Initial_Condition.
1370
1371 function Is_Declaration (N : Node_Id) return Boolean;
1372 -- Determine whether arbitrary node N denotes a declaration
1373
1374 function Is_Declared_Within_Variant (Comp : Entity_Id) return Boolean;
1375 -- Returns True iff component Comp is declared within a variant part
1376
1377 function Is_Dependent_Component_Of_Mutable_Object
1378 (Object : Node_Id) return Boolean;
1379 -- Returns True if Object is the name of a subcomponent that depends on
1380 -- discriminants of a variable whose nominal subtype is unconstrained and
1381 -- not indefinite, and the variable is not aliased. Otherwise returns
1382 -- False. The nodes passed to this function are assumed to denote objects.
1383
1384 function Is_Dereferenced (N : Node_Id) return Boolean;
1385 -- N is a subexpression node of an access type. This function returns true
1386 -- if N appears as the prefix of a node that does a dereference of the
1387 -- access value (selected/indexed component, explicit dereference or a
1388 -- slice), and false otherwise.
1389
1390 function Is_Descendant_Of (T1 : Entity_Id; T2 : Entity_Id) return Boolean;
1391 -- Returns True if type T1 is a descendant of type T2, and false otherwise.
1392 -- This is the RM definition, a type is a descendant of another type if it
1393 -- is the same type or is derived from a descendant of the other type.
1394
1395 function Is_Descendant_Of_Suspension_Object
1396 (Typ : Entity_Id) return Boolean;
1397 -- Determine whether type Typ is a descendant of type Suspension_Object
1398 -- defined in Ada.Synchronous_Task_Control. This version is different from
1399 -- Is_Descendant_Of as the detection of Suspension_Object does not involve
1400 -- an entity and by extension a call to RTSfind.
1401
1402 function Is_Double_Precision_Floating_Point_Type
1403 (E : Entity_Id) return Boolean;
1404 -- Return whether E is a double precision floating point type,
1405 -- characterized by:
1406 -- . machine_radix = 2
1407 -- . machine_mantissa = 53
1408 -- . machine_emax = 2**10
1409 -- . machine_emin = 3 - machine_emax
1410
1411 function Is_Effectively_Volatile (Id : Entity_Id) return Boolean;
1412 -- Determine whether a type or object denoted by entity Id is effectively
1413 -- volatile (SPARK RM 7.1.2). To qualify as such, the entity must be either
1414 -- * Volatile
1415 -- * An array type subject to aspect Volatile_Components
1416 -- * An array type whose component type is effectively volatile
1417 -- * A protected type
1418 -- * Descendant of type Ada.Synchronous_Task_Control.Suspension_Object
1419
1420 function Is_Effectively_Volatile_Object (N : Node_Id) return Boolean;
1421 -- Determine whether an arbitrary node denotes an effectively volatile
1422 -- object (SPARK RM 7.1.2).
1423
1424 function Is_Entry_Body (Id : Entity_Id) return Boolean;
1425 -- Determine whether entity Id is the body entity of an entry [family]
1426
1427 function Is_Entry_Declaration (Id : Entity_Id) return Boolean;
1428 -- Determine whether entity Id is the spec entity of an entry [family]
1429
1430 function Is_Expanded_Priority_Attribute (E : Entity_Id) return Boolean;
1431 -- Check whether a function in a call is an expanded priority attribute,
1432 -- which is transformed into an Rtsfind call to Get_Ceiling. This expansion
1433 -- does not take place in a configurable runtime.
1434
1435 function Is_Expression_Function (Subp : Entity_Id) return Boolean;
1436 -- Determine whether subprogram [body] Subp denotes an expression function
1437
1438 function Is_Expression_Function_Or_Completion
1439 (Subp : Entity_Id) return Boolean;
1440 -- Determine whether subprogram [body] Subp denotes an expression function
1441 -- or is completed by an expression function body.
1442
1443 function Is_EVF_Expression (N : Node_Id) return Boolean;
1444 -- Determine whether node N denotes a reference to a formal parameter of
1445 -- a specific tagged type whose related subprogram is subject to pragma
1446 -- Extensions_Visible with value "False" (SPARK RM 6.1.7). Several other
1447 -- constructs fall under this category:
1448 -- 1) A qualified expression whose operand is EVF
1449 -- 2) A type conversion whose operand is EVF
1450 -- 3) An if expression with at least one EVF dependent_expression
1451 -- 4) A case expression with at least one EVF dependent_expression
1452
1453 function Is_False (U : Uint) return Boolean;
1454 pragma Inline (Is_False);
1455 -- The argument is a Uint value which is the Boolean'Pos value of a Boolean
1456 -- operand (i.e. is either 0 for False, or 1 for True). This function tests
1457 -- if it is False (i.e. zero).
1458
1459 function Is_Fixed_Model_Number (U : Ureal; T : Entity_Id) return Boolean;
1460 -- Returns True iff the number U is a model number of the fixed-point type
1461 -- T, i.e. if it is an exact multiple of Small.
1462
1463 function Is_Fully_Initialized_Type (Typ : Entity_Id) return Boolean;
1464 -- Typ is a type entity. This function returns true if this type is fully
1465 -- initialized, meaning that an object of the type is fully initialized.
1466 -- Note that initialization resulting from use of pragma Normalize_Scalars
1467 -- does not count. Note that this is only used for the purpose of issuing
1468 -- warnings for objects that are potentially referenced uninitialized. This
1469 -- means that the result returned is not crucial, but should err on the
1470 -- side of thinking things are fully initialized if it does not know.
1471
1472 function Is_Generic_Declaration_Or_Body (Decl : Node_Id) return Boolean;
1473 -- Determine whether arbitrary declaration Decl denotes a generic package,
1474 -- a generic subprogram or a generic body.
1475
1476 function Is_Inherited_Operation (E : Entity_Id) return Boolean;
1477 -- E is a subprogram. Return True is E is an implicit operation inherited
1478 -- by a derived type declaration.
1479
1480 function Is_Inherited_Operation_For_Type
1481 (E : Entity_Id;
1482 Typ : Entity_Id) return Boolean;
1483 -- E is a subprogram. Return True is E is an implicit operation inherited
1484 -- by the derived type declaration for type Typ.
1485
1486 function Is_Iterator (Typ : Entity_Id) return Boolean;
1487 -- AI05-0139-2: Check whether Typ is one of the predefined interfaces in
1488 -- Ada.Iterator_Interfaces, or it is derived from one.
1489
1490 function Is_Iterator_Over_Array (N : Node_Id) return Boolean;
1491 -- N is an iterator specification. Returns True iff N is an iterator over
1492 -- an array, either inside a loop of the form 'for X of A' or a quantified
1493 -- expression of the form 'for all/some X of A' where A is of array type.
1494
1495 type Is_LHS_Result is (Yes, No, Unknown);
1496 function Is_LHS (N : Node_Id) return Is_LHS_Result;
1497 -- Returns Yes if N is definitely used as Name in an assignment statement.
1498 -- Returns No if N is definitely NOT used as a Name in an assignment
1499 -- statement. Returns Unknown if we can't tell at this stage (happens in
1500 -- the case where we don't know the type of N yet, and we have something
1501 -- like N.A := 3, where this counts as N being used on the left side of
1502 -- an assignment only if N is not an access type. If it is an access type
1503 -- then it is N.all.A that is assigned, not N.
1504
1505 function Is_Library_Level_Entity (E : Entity_Id) return Boolean;
1506 -- A library-level declaration is one that is accessible from Standard,
1507 -- i.e. a library unit or an entity declared in a library package.
1508
1509 function Is_Limited_Class_Wide_Type (Typ : Entity_Id) return Boolean;
1510 -- Determine whether a given type is a limited class-wide type, in which
1511 -- case it needs a Master_Id, because extensions of its designated type
1512 -- may include task components. A class-wide type that comes from a
1513 -- limited view must be treated in the same way.
1514
1515 function Is_Local_Variable_Reference (Expr : Node_Id) return Boolean;
1516 -- Determines whether Expr is a reference to a variable or IN OUT mode
1517 -- parameter of the current enclosing subprogram.
1518 -- Why are OUT parameters not considered here ???
1519
1520 function Is_Nontrivial_Default_Init_Cond_Procedure
1521 (Id : Entity_Id) return Boolean;
1522 -- Determine whether entity Id denotes the procedure that verifies the
1523 -- assertion expression of pragma Default_Initial_Condition and if it does,
1524 -- the encapsulated expression is nontrivial.
1525
1526 function Is_Null_Record_Type (T : Entity_Id) return Boolean;
1527 -- Determine whether T is declared with a null record definition or a
1528 -- null component list.
1529
1530 function Is_Object_Reference (N : Node_Id) return Boolean;
1531 -- Determines if the tree referenced by N represents an object. Both
1532 -- variable and constant objects return True (compare Is_Variable).
1533
1534 function Is_OK_Variable_For_Out_Formal (AV : Node_Id) return Boolean;
1535 -- Used to test if AV is an acceptable formal for an OUT or IN OUT formal.
1536 -- Note that the Is_Variable function is not quite the right test because
1537 -- this is a case in which conversions whose expression is a variable (in
1538 -- the Is_Variable sense) with an untagged type target are considered view
1539 -- conversions and hence variables.
1540
1541 function Is_OK_Volatile_Context
1542 (Context : Node_Id;
1543 Obj_Ref : Node_Id) return Boolean;
1544 -- Determine whether node Context denotes a "non-interfering context" (as
1545 -- defined in SPARK RM 7.1.3(12)) where volatile reference Obj_Ref can
1546 -- safely reside.
1547
1548 function Is_Package_Contract_Annotation (Item : Node_Id) return Boolean;
1549 -- Determine whether aspect specification or pragma Item is one of the
1550 -- following package contract annotations:
1551 -- Abstract_State
1552 -- Initial_Condition
1553 -- Initializes
1554 -- Refined_State
1555
1556 function Is_Partially_Initialized_Type
1557 (Typ : Entity_Id;
1558 Include_Implicit : Boolean := True) return Boolean;
1559 -- Typ is a type entity. This function returns true if this type is partly
1560 -- initialized, meaning that an object of the type is at least partly
1561 -- initialized (in particular in the record case, that at least one
1562 -- component has an initialization expression). Note that initialization
1563 -- resulting from the use of pragma Normalize_Scalars does not count.
1564 -- Include_Implicit controls whether implicit initialization of access
1565 -- values to null, and of discriminant values, is counted as making the
1566 -- type be partially initialized. For the default setting of True, these
1567 -- implicit cases do count, and discriminated types or types containing
1568 -- access values not explicitly initialized will return True. Otherwise
1569 -- if Include_Implicit is False, these cases do not count as making the
1570 -- type be partially initialized.
1571
1572 function Is_Potentially_Unevaluated (N : Node_Id) return Boolean;
1573 -- Predicate to implement definition given in RM 6.1.1 (20/3)
1574
1575 function Is_Potentially_Persistent_Type (T : Entity_Id) return Boolean;
1576 -- Determines if type T is a potentially persistent type. A potentially
1577 -- persistent type is defined (recursively) as a scalar type, an untagged
1578 -- record whose components are all of a potentially persistent type, or an
1579 -- array with all static constraints whose component type is potentially
1580 -- persistent. A private type is potentially persistent if the full type
1581 -- is potentially persistent.
1582
1583 function Is_Protected_Self_Reference (N : Node_Id) return Boolean;
1584 -- Return True if node N denotes a protected type name which represents
1585 -- the current instance of a protected object according to RM 9.4(21/2).
1586
1587 function Is_RCI_Pkg_Spec_Or_Body (Cunit : Node_Id) return Boolean;
1588 -- Return True if a compilation unit is the specification or the
1589 -- body of a remote call interface package.
1590
1591 function Is_Remote_Access_To_Class_Wide_Type (E : Entity_Id) return Boolean;
1592 -- Return True if E is a remote access-to-class-wide type
1593
1594 function Is_Remote_Access_To_Subprogram_Type (E : Entity_Id) return Boolean;
1595 -- Return True if E is a remote access to subprogram type
1596
1597 function Is_Remote_Call (N : Node_Id) return Boolean;
1598 -- Return True if N denotes a potentially remote call
1599
1600 function Is_Renamed_Entry (Proc_Nam : Entity_Id) return Boolean;
1601 -- Return True if Proc_Nam is a procedure renaming of an entry
1602
1603 function Is_Renaming_Declaration (N : Node_Id) return Boolean;
1604 -- Determine whether arbitrary node N denotes a renaming declaration
1605
1606 function Is_Reversible_Iterator (Typ : Entity_Id) return Boolean;
1607 -- AI05-0139-2: Check whether Typ is derived from the predefined interface
1608 -- Ada.Iterator_Interfaces.Reversible_Iterator.
1609
1610 function Is_Selector_Name (N : Node_Id) return Boolean;
1611 -- Given an N_Identifier node N, determines if it is a Selector_Name.
1612 -- As described in Sinfo, Selector_Names are special because they
1613 -- represent use of the N_Identifier node for a true identifier, when
1614 -- normally such nodes represent a direct name.
1615
1616 function Is_Single_Concurrent_Object (Id : Entity_Id) return Boolean;
1617 -- Determine whether arbitrary entity Id denotes the anonymous object
1618 -- created for a single protected or single task type.
1619
1620 function Is_Single_Concurrent_Type (Id : Entity_Id) return Boolean;
1621 -- Determine whether arbitrary entity Id denotes a single protected or
1622 -- single task type.
1623
1624 function Is_Single_Concurrent_Type_Declaration (N : Node_Id) return Boolean;
1625 -- Determine whether arbitrary node N denotes the declaration of a single
1626 -- protected type or single task type.
1627
1628 function Is_Single_Precision_Floating_Point_Type
1629 (E : Entity_Id) return Boolean;
1630 -- Return whether E is a single precision floating point type,
1631 -- characterized by:
1632 -- . machine_radix = 2
1633 -- . machine_mantissa = 24
1634 -- . machine_emax = 2**7
1635 -- . machine_emin = 3 - machine_emax
1636
1637 function Is_Single_Protected_Object (Id : Entity_Id) return Boolean;
1638 -- Determine whether arbitrary entity Id denotes the anonymous object
1639 -- created for a single protected type.
1640
1641 function Is_Single_Task_Object (Id : Entity_Id) return Boolean;
1642 -- Determine whether arbitrary entity Id denotes the anonymous object
1643 -- created for a single task type.
1644
1645 function Is_SPARK_05_Initialization_Expr (N : Node_Id) return Boolean;
1646 -- Determines if the tree referenced by N represents an initialization
1647 -- expression in SPARK 2005, suitable for initializing an object in an
1648 -- object declaration.
1649
1650 function Is_SPARK_05_Object_Reference (N : Node_Id) return Boolean;
1651 -- Determines if the tree referenced by N represents an object in SPARK
1652 -- 2005. This differs from Is_Object_Reference in that only variables,
1653 -- constants, formal parameters, and selected_components of those are
1654 -- valid objects in SPARK 2005.
1655
1656 function Is_Specific_Tagged_Type (Typ : Entity_Id) return Boolean;
1657 -- Determine whether an arbitrary [private] type is specifically tagged
1658
1659 function Is_Statement (N : Node_Id) return Boolean;
1660 pragma Inline (Is_Statement);
1661 -- Check if the node N is a statement node. Note that this includes
1662 -- the case of procedure call statements (unlike the direct use of
1663 -- the N_Statement_Other_Than_Procedure_Call subtype from Sinfo).
1664 -- Note that a label is *not* a statement, and will return False.
1665
1666 function Is_Subprogram_Contract_Annotation (Item : Node_Id) return Boolean;
1667 -- Determine whether aspect specification or pragma Item is one of the
1668 -- following subprogram contract annotations:
1669 -- Contract_Cases
1670 -- Depends
1671 -- Extensions_Visible
1672 -- Global
1673 -- Post
1674 -- Post_Class
1675 -- Postcondition
1676 -- Pre
1677 -- Pre_Class
1678 -- Precondition
1679 -- Refined_Depends
1680 -- Refined_Global
1681 -- Refined_Post
1682 -- Test_Case
1683
1684 function Is_Subprogram_Stub_Without_Prior_Declaration
1685 (N : Node_Id) return Boolean;
1686 -- Return True if N is a subprogram stub with no prior subprogram
1687 -- declaration.
1688
1689 function Is_Suspension_Object (Id : Entity_Id) return Boolean;
1690 -- Determine whether arbitrary entity Id denotes Suspension_Object defined
1691 -- in Ada.Synchronous_Task_Control.
1692
1693 function Is_Synchronized_Object (Id : Entity_Id) return Boolean;
1694 -- Determine whether entity Id denotes an object and if it does, whether
1695 -- this object is synchronized as specified in SPARK RM 9.1. To qualify as
1696 -- such, the object must be
1697 -- * Of a type that yields a synchronized object
1698 -- * An atomic object with enabled Async_Writers
1699 -- * A constant
1700 -- * A variable subject to pragma Constant_After_Elaboration
1701
1702 function Is_Synchronized_Tagged_Type (E : Entity_Id) return Boolean;
1703 -- Returns True if E is a synchronized tagged type (AARM 3.9.4 (6/2))
1704
1705 function Is_Transfer (N : Node_Id) return Boolean;
1706 -- Returns True if the node N is a statement which is known to cause an
1707 -- unconditional transfer of control at runtime, i.e. the following
1708 -- statement definitely will not be executed.
1709
1710 function Is_True (U : Uint) return Boolean;
1711 pragma Inline (Is_True);
1712 -- The argument is a Uint value which is the Boolean'Pos value of a Boolean
1713 -- operand (i.e. is either 0 for False, or 1 for True). This function tests
1714 -- if it is True (i.e. non-zero).
1715
1716 function Is_Unchecked_Conversion_Instance (Id : Entity_Id) return Boolean;
1717 -- Determine whether an arbitrary entity denotes an instance of function
1718 -- Ada.Unchecked_Conversion.
1719
1720 function Is_Universal_Numeric_Type (T : Entity_Id) return Boolean;
1721 pragma Inline (Is_Universal_Numeric_Type);
1722 -- True if T is Universal_Integer or Universal_Real
1723
1724 function Is_Variable_Size_Array (E : Entity_Id) return Boolean;
1725 -- Returns true if E has variable size components
1726
1727 function Is_Variable_Size_Record (E : Entity_Id) return Boolean;
1728 -- Returns true if E has variable size components
1729
1730 function Is_Variable
1731 (N : Node_Id;
1732 Use_Original_Node : Boolean := True) return Boolean;
1733 -- Determines if the tree referenced by N represents a variable, i.e. can
1734 -- appear on the left side of an assignment. There is one situation (formal
1735 -- parameters) in which untagged type conversions are also considered
1736 -- variables, but Is_Variable returns False for such cases, since it has
1737 -- no knowledge of the context. Note that this is the point at which
1738 -- Assignment_OK is checked, and True is returned for any tree thus marked.
1739 -- Use_Original_Node is used to perform the test on Original_Node (N). By
1740 -- default is True since this routine is commonly invoked as part of the
1741 -- semantic analysis and it must not be disturbed by the rewriten nodes.
1742
1743 function Is_Visibly_Controlled (T : Entity_Id) return Boolean;
1744 -- Check whether T is derived from a visibly controlled type. This is true
1745 -- if the root type is declared in Ada.Finalization. If T is derived
1746 -- instead from a private type whose full view is controlled, an explicit
1747 -- Initialize/Adjust/Finalize subprogram does not override the inherited
1748 -- one.
1749
1750 function Is_Volatile_Function (Func_Id : Entity_Id) return Boolean;
1751 -- Determine whether [generic] function Func_Id is subject to enabled
1752 -- pragma Volatile_Function. Protected functions are treated as volatile
1753 -- (SPARK RM 7.1.2).
1754
1755 function Is_Volatile_Object (N : Node_Id) return Boolean;
1756 -- Determines if the given node denotes an volatile object in the sense of
1757 -- the legality checks described in RM C.6(12). Note that the test here is
1758 -- for something actually declared as volatile, not for an object that gets
1759 -- treated as volatile (see Einfo.Treat_As_Volatile).
1760
1761 function Itype_Has_Declaration (Id : Entity_Id) return Boolean;
1762 -- Applies to Itypes. True if the Itype is attached to a declaration for
1763 -- the type through its Parent field, which may or not be present in the
1764 -- tree.
1765
1766 procedure Kill_Current_Values (Last_Assignment_Only : Boolean := False);
1767 -- This procedure is called to clear all constant indications from all
1768 -- entities in the current scope and in any parent scopes if the current
1769 -- scope is a block or a package (and that recursion continues to the top
1770 -- scope that is not a block or a package). This is used when the
1771 -- sequential flow-of-control assumption is violated (occurrence of a
1772 -- label, head of a loop, or start of an exception handler). The effect of
1773 -- the call is to clear the Current_Value field (but we do not need to
1774 -- clear the Is_True_Constant flag, since that only gets reset if there
1775 -- really is an assignment somewhere in the entity scope). This procedure
1776 -- also calls Kill_All_Checks, since this is a special case of needing to
1777 -- forget saved values. This procedure also clears the Is_Known_Null and
1778 -- Is_Known_Non_Null and Is_Known_Valid flags in variables, constants or
1779 -- parameters since these are also not known to be trustable any more.
1780 --
1781 -- The Last_Assignment_Only flag is set True to clear only Last_Assignment
1782 -- fields and leave other fields unchanged. This is used when we encounter
1783 -- an unconditional flow of control change (return, goto, raise). In such
1784 -- cases we don't need to clear the current values, since it may be that
1785 -- the flow of control change occurs in a conditional context, and if it
1786 -- is not taken, then it is just fine to keep the current values. But the
1787 -- Last_Assignment field is different, if we have a sequence assign-to-v,
1788 -- conditional-return, assign-to-v, we do not want to complain that the
1789 -- second assignment clobbers the first.
1790
1791 procedure Kill_Current_Values
1792 (Ent : Entity_Id;
1793 Last_Assignment_Only : Boolean := False);
1794 -- This performs the same processing as described above for the form with
1795 -- no argument, but for the specific entity given. The call has no effect
1796 -- if the entity Ent is not for an object. Last_Assignment_Only has the
1797 -- same meaning as for the call with no Ent.
1798
1799 procedure Kill_Size_Check_Code (E : Entity_Id);
1800 -- Called when an address clause or pragma Import is applied to an entity.
1801 -- If the entity is a variable or a constant, and size check code is
1802 -- present, this size check code is killed, since the object will not be
1803 -- allocated by the program.
1804
1805 function Known_To_Be_Assigned (N : Node_Id) return Boolean;
1806 -- The node N is an entity reference. This function determines whether the
1807 -- reference is for sure an assignment of the entity, returning True if
1808 -- so. This differs from May_Be_Lvalue in that it defaults in the other
1809 -- direction. Cases which may possibly be assignments but are not known to
1810 -- be may return True from May_Be_Lvalue, but False from this function.
1811
1812 function Last_Source_Statement (HSS : Node_Id) return Node_Id;
1813 -- HSS is a handled statement sequence. This function returns the last
1814 -- statement in Statements (HSS) that has Comes_From_Source set. If no
1815 -- such statement exists, Empty is returned.
1816
1817 function Matching_Static_Array_Bounds
1818 (L_Typ : Node_Id;
1819 R_Typ : Node_Id) return Boolean;
1820 -- L_Typ and R_Typ are two array types. Returns True when they have the
1821 -- same number of dimensions, and the same static bounds for each index
1822 -- position.
1823
1824 procedure Mark_Coextensions (Context_Nod : Node_Id; Root_Nod : Node_Id);
1825 -- Given a node which designates the context of analysis and an origin in
1826 -- the tree, traverse from Root_Nod and mark all allocators as either
1827 -- dynamic or static depending on Context_Nod. Any incorrect marking is
1828 -- cleaned up during resolution.
1829
1830 function May_Be_Lvalue (N : Node_Id) return Boolean;
1831 -- Determines if N could be an lvalue (e.g. an assignment left hand side).
1832 -- An lvalue is defined as any expression which appears in a context where
1833 -- a name is required by the syntax, and the identity, rather than merely
1834 -- the value of the node is needed (for example, the prefix of an Access
1835 -- attribute is in this category). Note that, as implied by the name, this
1836 -- test is conservative. If it cannot be sure that N is NOT an lvalue, then
1837 -- it returns True. It tries hard to get the answer right, but it is hard
1838 -- to guarantee this in all cases. Note that it is more possible to give
1839 -- correct answer if the tree is fully analyzed.
1840
1841 function Needs_One_Actual (E : Entity_Id) return Boolean;
1842 -- Returns True if a function has defaults for all but its first
1843 -- formal. Used in Ada 2005 mode to solve the syntactic ambiguity that
1844 -- results from an indexing of a function call written in prefix form.
1845
1846 function New_Copy_List_Tree (List : List_Id) return List_Id;
1847 -- Copy recursively an analyzed list of nodes. Uses New_Copy_Tree defined
1848 -- below. As for New_Copy_Tree, it is illegal to attempt to copy extended
1849 -- nodes (entities) either directly or indirectly using this function.
1850
1851 function New_Copy_Tree
1852 (Source : Node_Id;
1853 Map : Elist_Id := No_Elist;
1854 New_Sloc : Source_Ptr := No_Location;
1855 New_Scope : Entity_Id := Empty) return Node_Id;
1856 -- Given a node that is the root of a subtree, Copy_Tree copies the entire
1857 -- syntactic subtree, including recursively any descendants whose parent
1858 -- field references a copied node (descendants not linked to a copied node
1859 -- by the parent field are not copied, instead the copied tree references
1860 -- the same descendant as the original in this case, which is appropriate
1861 -- for non-syntactic fields such as Etype). The parent pointers in the
1862 -- copy are properly set. Copy_Tree (Empty/Error) returns Empty/Error.
1863 -- The one exception to the rule of not copying semantic fields is that
1864 -- any implicit types attached to the subtree are duplicated, so that
1865 -- the copy contains a distinct set of implicit type entities. Thus this
1866 -- function is used when it is necessary to duplicate an analyzed tree,
1867 -- declared in the same or some other compilation unit. This function is
1868 -- declared here rather than in atree because it uses semantic information
1869 -- in particular concerning the structure of itypes and the generation of
1870 -- public symbols.
1871
1872 -- The Map argument, if set to a non-empty Elist, specifies a set of
1873 -- mappings to be applied to entities in the tree. The map has the form:
1874 --
1875 -- old entity 1
1876 -- new entity to replace references to entity 1
1877 -- old entity 2
1878 -- new entity to replace references to entity 2
1879 -- ...
1880 --
1881 -- The call destroys the contents of Map in this case
1882 --
1883 -- The parameter New_Sloc, if set to a value other than No_Location, is
1884 -- used as the Sloc value for all nodes in the new copy. If New_Sloc is
1885 -- set to its default value No_Location, then the Sloc values of the
1886 -- nodes in the copy are simply copied from the corresponding original.
1887 --
1888 -- The Comes_From_Source indication is unchanged if New_Sloc is set to
1889 -- the default No_Location value, but is reset if New_Sloc is given, since
1890 -- in this case the result clearly is neither a source node or an exact
1891 -- copy of a source node.
1892 --
1893 -- The parameter New_Scope, if set to a value other than Empty, is the
1894 -- value to use as the Scope for any Itypes that are copied. The most
1895 -- typical value for this parameter, if given, is Current_Scope.
1896
1897 function New_External_Entity
1898 (Kind : Entity_Kind;
1899 Scope_Id : Entity_Id;
1900 Sloc_Value : Source_Ptr;
1901 Related_Id : Entity_Id;
1902 Suffix : Character;
1903 Suffix_Index : Nat := 0;
1904 Prefix : Character := ' ') return Entity_Id;
1905 -- This function creates an N_Defining_Identifier node for an internal
1906 -- created entity, such as an implicit type or subtype, or a record
1907 -- initialization procedure. The entity name is constructed with a call
1908 -- to New_External_Name (Related_Id, Suffix, Suffix_Index, Prefix), so
1909 -- that the generated name may be referenced as a public entry, and the
1910 -- Is_Public flag is set if needed (using Set_Public_Status). If the
1911 -- entity is for a type or subtype, the size/align fields are initialized
1912 -- to unknown (Uint_0).
1913
1914 function New_Internal_Entity
1915 (Kind : Entity_Kind;
1916 Scope_Id : Entity_Id;
1917 Sloc_Value : Source_Ptr;
1918 Id_Char : Character) return Entity_Id;
1919 -- This function is similar to New_External_Entity, except that the
1920 -- name is constructed by New_Internal_Name (Id_Char). This is used
1921 -- when the resulting entity does not have to be referenced as a
1922 -- public entity (and in this case Is_Public is not set).
1923
1924 procedure Next_Actual (Actual_Id : in out Node_Id);
1925 pragma Inline (Next_Actual);
1926 -- Next_Actual (N) is equivalent to N := Next_Actual (N). Note that we
1927 -- inline this procedural form, but not the functional form that follows.
1928
1929 function Next_Actual (Actual_Id : Node_Id) return Node_Id;
1930 -- Find next actual parameter in declaration order. As described for
1931 -- First_Actual, this is the next actual in the declaration order, not
1932 -- the call order, so this does not correspond to simply taking the
1933 -- next entry of the Parameter_Associations list. The argument is an
1934 -- actual previously returned by a call to First_Actual or Next_Actual.
1935 -- Note that the result produced is always an expression, not a parameter
1936 -- association node, even if named notation was used.
1937
1938 procedure Normalize_Actuals
1939 (N : Node_Id;
1940 S : Entity_Id;
1941 Report : Boolean;
1942 Success : out Boolean);
1943 -- Reorders lists of actuals according to names of formals, value returned
1944 -- in Success indicates success of reordering. For more details, see body.
1945 -- Errors are reported only if Report is set to True.
1946
1947 procedure Note_Possible_Modification (N : Node_Id; Sure : Boolean);
1948 -- This routine is called if the sub-expression N maybe the target of
1949 -- an assignment (e.g. it is the left side of an assignment, used as
1950 -- an out parameters, or used as prefixes of access attributes). It
1951 -- sets May_Be_Modified in the associated entity if there is one,
1952 -- taking into account the rule that in the case of renamed objects,
1953 -- it is the flag in the renamed object that must be set.
1954 --
1955 -- The parameter Sure is set True if the modification is sure to occur
1956 -- (e.g. target of assignment, or out parameter), and to False if the
1957 -- modification is only potential (e.g. address of entity taken).
1958
1959 function Null_To_Null_Address_Convert_OK
1960 (N : Node_Id;
1961 Typ : Entity_Id := Empty) return Boolean;
1962 -- Return True if we are compiling in relaxed RM semantics mode and:
1963 -- 1) N is a N_Null node and Typ is a descendant of System.Address, or
1964 -- 2) N is a comparison operator, one of the operands is null, and the
1965 -- type of the other operand is a descendant of System.Address.
1966
1967 function Object_Access_Level (Obj : Node_Id) return Uint;
1968 -- Return the accessibility level of the view of the object Obj. For
1969 -- convenience, qualified expressions applied to object names are also
1970 -- allowed as actuals for this function.
1971
1972 function Original_Aspect_Pragma_Name (N : Node_Id) return Name_Id;
1973 -- Retrieve the name of aspect or pragma N taking into account a possible
1974 -- rewrite and whether the pragma is generated from an aspect as the names
1975 -- may be different. The routine also deals with 'Class in which case it
1976 -- returns the following values:
1977 --
1978 -- Invariant -> Name_uInvariant
1979 -- Post'Class -> Name_uPost
1980 -- Pre'Class -> Name_uPre
1981 -- Type_Invariant -> Name_uType_Invariant
1982 -- Type_Invariant'Class -> Name_uType_Invariant
1983
1984 function Original_Corresponding_Operation (S : Entity_Id) return Entity_Id;
1985 -- [Ada 2012: AI05-0125-1]: If S is an inherited dispatching primitive S2,
1986 -- or overrides an inherited dispatching primitive S2, the original
1987 -- corresponding operation of S is the original corresponding operation of
1988 -- S2. Otherwise, it is S itself.
1989
1990 procedure Output_Entity (Id : Entity_Id);
1991 -- Print entity Id to standard output. The name of the entity appears in
1992 -- fully qualified form.
1993 --
1994 -- WARNING: this routine should be used in debugging scenarios such as
1995 -- tracking down undefined symbols as it is fairly low level.
1996
1997 procedure Output_Name (Nam : Name_Id; Scop : Entity_Id := Current_Scope);
1998 -- Print name Nam to standard output. The name appears in fully qualified
1999 -- form assuming it appears in scope Scop. Note that this may not reflect
2000 -- the final qualification as the entity which carries the name may be
2001 -- relocated to a different scope.
2002 --
2003 -- WARNING: this routine should be used in debugging scenarios such as
2004 -- tracking down undefined symbols as it is fairly low level.
2005
2006 function Policy_In_Effect (Policy : Name_Id) return Name_Id;
2007 -- Given a policy, return the policy identifier associated with it. If no
2008 -- such policy is in effect, the value returned is No_Name.
2009
2010 function Predicate_Tests_On_Arguments (Subp : Entity_Id) return Boolean;
2011 -- Subp is the entity for a subprogram call. This function returns True if
2012 -- predicate tests are required for the arguments in this call (this is the
2013 -- normal case). It returns False for special cases where these predicate
2014 -- tests should be skipped (see body for details).
2015
2016 function Primitive_Names_Match (E1, E2 : Entity_Id) return Boolean;
2017 -- Returns True if the names of both entities correspond with matching
2018 -- primitives. This routine includes support for the case in which one
2019 -- or both entities correspond with entities built by Derive_Subprogram
2020 -- with a special name to avoid being overridden (i.e. return true in case
2021 -- of entities with names "nameP" and "name" or vice versa).
2022
2023 function Private_Component (Type_Id : Entity_Id) return Entity_Id;
2024 -- Returns some private component (if any) of the given Type_Id.
2025 -- Used to enforce the rules on visibility of operations on composite
2026 -- types, that depend on the full view of the component type. For a
2027 -- record type there may be several such components, we just return
2028 -- the first one.
2029
2030 procedure Process_End_Label
2031 (N : Node_Id;
2032 Typ : Character;
2033 Ent : Entity_Id);
2034 -- N is a node whose End_Label is to be processed, generating all
2035 -- appropriate cross-reference entries, and performing style checks
2036 -- for any identifier references in the end label. Typ is either
2037 -- 'e' or 't indicating the type of the cross-reference entity
2038 -- (e for spec, t for body, see Lib.Xref spec for details). The
2039 -- parameter Ent gives the entity to which the End_Label refers,
2040 -- and to which cross-references are to be generated.
2041
2042 procedure Propagate_Invariant_Attributes
2043 (Typ : Entity_Id;
2044 From_Typ : Entity_Id);
2045 -- Inherit all invariant-related attributes form type From_Typ. Typ is the
2046 -- destination type.
2047
2048 procedure Propagate_Concurrent_Flags
2049 (Typ : Entity_Id;
2050 Comp_Typ : Entity_Id);
2051 -- Set Has_Task, Has_Protected and Has_Timing_Event on Typ when the flags
2052 -- are set on Comp_Typ. This follows the definition of these flags which
2053 -- are set (recursively) on any composite type which has a component marked
2054 -- by one of these flags. This procedure can only set flags for Typ, and
2055 -- never clear them. Comp_Typ is the type of a component or a parent.
2056
2057 procedure Record_Possible_Part_Of_Reference
2058 (Var_Id : Entity_Id;
2059 Ref : Node_Id);
2060 -- Save reference Ref to variable Var_Id when the variable is subject to
2061 -- pragma Part_Of. If the variable is known to be a constituent of a single
2062 -- protected/task type, the legality of the reference is verified and the
2063 -- save does not take place.
2064
2065 function Referenced (Id : Entity_Id; Expr : Node_Id) return Boolean;
2066 -- Determine whether entity Id is referenced within expression Expr
2067
2068 function References_Generic_Formal_Type (N : Node_Id) return Boolean;
2069 -- Returns True if the expression Expr contains any references to a generic
2070 -- type. This can only happen within a generic template.
2071
2072 procedure Remove_Homonym (E : Entity_Id);
2073 -- Removes E from the homonym chain
2074
2075 procedure Remove_Overloaded_Entity (Id : Entity_Id);
2076 -- Remove arbitrary entity Id from the homonym chain, the scope chain and
2077 -- the primitive operations list of the associated controlling type. NOTE:
2078 -- the removal performed by this routine does not affect the visibility of
2079 -- existing homonyms.
2080
2081 function Remove_Suffix (E : Entity_Id; Suffix : Character) return Name_Id;
2082 -- Returns the name of E without Suffix
2083
2084 procedure Replace_Null_By_Null_Address (N : Node_Id);
2085 -- N is N_Null or a binary comparison operator, we are compiling in relaxed
2086 -- RM semantics mode, and one of the operands is null. Replace null with
2087 -- System.Null_Address.
2088
2089 function Rep_To_Pos_Flag (E : Entity_Id; Loc : Source_Ptr) return Node_Id;
2090 -- This is used to construct the second argument in a call to Rep_To_Pos
2091 -- which is Standard_True if range checks are enabled (E is an entity to
2092 -- which the Range_Checks_Suppressed test is applied), and Standard_False
2093 -- if range checks are suppressed. Loc is the location for the node that
2094 -- is returned (which is a New_Occurrence of the appropriate entity).
2095 --
2096 -- Note: one might think that it would be fine to always use True and
2097 -- to ignore the suppress in this case, but it is generally better to
2098 -- believe a request to suppress exceptions if possible, and further
2099 -- more there is at least one case in the generated code (the code for
2100 -- array assignment in a loop) that depends on this suppression.
2101
2102 procedure Require_Entity (N : Node_Id);
2103 -- N is a node which should have an entity value if it is an entity name.
2104 -- If not, then check if there were previous errors. If so, just fill
2105 -- in with Any_Id and ignore. Otherwise signal a program error exception.
2106 -- This is used as a defense mechanism against ill-formed trees caused by
2107 -- previous errors (particularly in -gnatq mode).
2108
2109 function Requires_Transient_Scope (Id : Entity_Id) return Boolean;
2110 -- Id is a type entity. The result is True when temporaries of this type
2111 -- need to be wrapped in a transient scope to be reclaimed properly when a
2112 -- secondary stack is in use. Examples of types requiring such wrapping are
2113 -- controlled types and variable-sized types including unconstrained
2114 -- arrays.
2115
2116 procedure Reset_Analyzed_Flags (N : Node_Id);
2117 -- Reset the Analyzed flags in all nodes of the tree whose root is N
2118
2119 procedure Restore_SPARK_Mode (Mode : SPARK_Mode_Type);
2120 -- Set the current SPARK_Mode to whatever Mode denotes. This routime must
2121 -- be used in tandem with Save_SPARK_Mode_And_Set.
2122
2123 function Returns_Unconstrained_Type (Subp : Entity_Id) return Boolean;
2124 -- Return true if Subp is a function that returns an unconstrained type
2125
2126 function Root_Type_Of_Full_View (T : Entity_Id) return Entity_Id;
2127 -- Similar to attribute Root_Type, but this version always follows the
2128 -- Full_View of a private type (if available) while searching for the
2129 -- ultimate derivation ancestor.
2130
2131 function Safe_To_Capture_Value
2132 (N : Node_Id;
2133 Ent : Entity_Id;
2134 Cond : Boolean := False) return Boolean;
2135 -- The caller is interested in capturing a value (either the current value,
2136 -- or an indication that the value is non-null) for the given entity Ent.
2137 -- This value can only be captured if sequential execution semantics can be
2138 -- properly guaranteed so that a subsequent reference will indeed be sure
2139 -- that this current value indication is correct. The node N is the
2140 -- construct which resulted in the possible capture of the value (this
2141 -- is used to check if we are in a conditional).
2142 --
2143 -- Cond is used to skip the test for being inside a conditional. It is used
2144 -- in the case of capturing values from if/while tests, which already do a
2145 -- proper job of handling scoping issues without this help.
2146 --
2147 -- The only entities whose values can be captured are OUT and IN OUT formal
2148 -- parameters, and variables unless Cond is True, in which case we also
2149 -- allow IN formals, loop parameters and constants, where we cannot ever
2150 -- capture actual value information, but we can capture conditional tests.
2151
2152 function Same_Name (N1, N2 : Node_Id) return Boolean;
2153 -- Determine if two (possibly expanded) names are the same name. This is
2154 -- a purely syntactic test, and N1 and N2 need not be analyzed.
2155
2156 function Same_Object (Node1, Node2 : Node_Id) return Boolean;
2157 -- Determine if Node1 and Node2 are known to designate the same object.
2158 -- This is a semantic test and both nodes must be fully analyzed. A result
2159 -- of True is decisively correct. A result of False does not necessarily
2160 -- mean that different objects are designated, just that this could not
2161 -- be reliably determined at compile time.
2162
2163 function Same_Type (T1, T2 : Entity_Id) return Boolean;
2164 -- Determines if T1 and T2 represent exactly the same type. Two types
2165 -- are the same if they are identical, or if one is an unconstrained
2166 -- subtype of the other, or they are both common subtypes of the same
2167 -- type with identical constraints. The result returned is conservative.
2168 -- It is True if the types are known to be the same, but a result of
2169 -- False is indecisive (e.g. the compiler may not be able to tell that
2170 -- two constraints are identical).
2171
2172 function Same_Value (Node1, Node2 : Node_Id) return Boolean;
2173 -- Determines if Node1 and Node2 are known to be the same value, which is
2174 -- true if they are both compile time known values and have the same value,
2175 -- or if they are the same object (in the sense of function Same_Object).
2176 -- A result of False does not necessarily mean they have different values,
2177 -- just that it is not possible to determine they have the same value.
2178
2179 procedure Save_SPARK_Mode_And_Set
2180 (Context : Entity_Id;
2181 Mode : out SPARK_Mode_Type);
2182 -- Save the current SPARK_Mode in effect in Mode. Establish the SPARK_Mode
2183 -- (if any) of a package or a subprogram denoted by Context. This routine
2184 -- must be used in tandem with Restore_SPARK_Mode.
2185
2186 function Scalar_Part_Present (T : Entity_Id) return Boolean;
2187 -- Tests if type T can be determined at compile time to have at least one
2188 -- scalar part in the sense of the Valid_Scalars attribute. Returns True if
2189 -- this is the case, and False if no scalar parts are present (meaning that
2190 -- the result of Valid_Scalars applied to T is always vacuously True).
2191
2192 function Scope_Within_Or_Same (Scope1, Scope2 : Entity_Id) return Boolean;
2193 -- Determines if the entity Scope1 is the same as Scope2, or if it is
2194 -- inside it, where both entities represent scopes. Note that scopes
2195 -- are only partially ordered, so Scope_Within_Or_Same (A,B) and
2196 -- Scope_Within_Or_Same (B,A) can both be False for a given pair A,B.
2197
2198 function Scope_Within (Scope1, Scope2 : Entity_Id) return Boolean;
2199 -- Like Scope_Within_Or_Same, except that this function returns
2200 -- False in the case where Scope1 and Scope2 are the same scope.
2201
2202 procedure Set_Convention (E : Entity_Id; Val : Convention_Id);
2203 -- Same as Basic_Set_Convention, but with an extra check for access types.
2204 -- In particular, if E is an access-to-subprogram type, and Val is a
2205 -- foreign convention, then we set Can_Use_Internal_Rep to False on E.
2206 -- Also, if the Etype of E is set and is an anonymous access type with
2207 -- no convention set, this anonymous type inherits the convention of E.
2208
2209 procedure Set_Current_Entity (E : Entity_Id);
2210 pragma Inline (Set_Current_Entity);
2211 -- Establish the entity E as the currently visible definition of its
2212 -- associated name (i.e. the Node_Id associated with its name).
2213
2214 procedure Set_Debug_Info_Needed (T : Entity_Id);
2215 -- Sets the Debug_Info_Needed flag on entity T , and also on any entities
2216 -- that are needed by T (for an object, the type of the object is needed,
2217 -- and for a type, various subsidiary types are needed -- see body for
2218 -- details). Never has any effect on T if the Debug_Info_Off flag is set.
2219 -- This routine should always be used instead of Set_Needs_Debug_Info to
2220 -- ensure that subsidiary entities are properly handled.
2221
2222 procedure Set_Entity_With_Checks (N : Node_Id; Val : Entity_Id);
2223 -- This procedure has the same calling sequence as Set_Entity, but it
2224 -- performs additional checks as follows:
2225 --
2226 -- If Style_Check is set, then it calls a style checking routine which
2227 -- can check identifier spelling style. This procedure also takes care
2228 -- of checking the restriction No_Implementation_Identifiers.
2229 --
2230 -- If restriction No_Abort_Statements is set, then it checks that the
2231 -- entity is not Ada.Task_Identification.Abort_Task.
2232 --
2233 -- If restriction No_Dynamic_Attachment is set, then it checks that the
2234 -- entity is not one of the restricted names for this restriction.
2235 --
2236 -- If restriction No_Long_Long_Integers is set, then it checks that the
2237 -- entity is not Standard.Long_Long_Integer.
2238 --
2239 -- If restriction No_Implementation_Identifiers is set, then it checks
2240 -- that the entity is not implementation defined.
2241
2242 procedure Set_Name_Entity_Id (Id : Name_Id; Val : Entity_Id);
2243 pragma Inline (Set_Name_Entity_Id);
2244 -- Sets the Entity_Id value associated with the given name, which is the
2245 -- Id of the innermost visible entity with the given name. See the body
2246 -- of package Sem_Ch8 for further details on the handling of visibility.
2247
2248 procedure Set_Next_Actual (Ass1_Id : Node_Id; Ass2_Id : Node_Id);
2249 -- The arguments may be parameter associations, whose descendants
2250 -- are the optional formal name and the actual parameter. Positional
2251 -- parameters are already members of a list, and do not need to be
2252 -- chained separately. See also First_Actual and Next_Actual.
2253
2254 procedure Set_Optimize_Alignment_Flags (E : Entity_Id);
2255 pragma Inline (Set_Optimize_Alignment_Flags);
2256 -- Sets Optimize_Alignment_Space/Time flags in E from current settings
2257
2258 procedure Set_Public_Status (Id : Entity_Id);
2259 -- If an entity (visible or otherwise) is defined in a library
2260 -- package, or a package that is itself public, then this subprogram
2261 -- labels the entity public as well.
2262
2263 procedure Set_Referenced_Modified (N : Node_Id; Out_Param : Boolean);
2264 -- N is the node for either a left hand side (Out_Param set to False),
2265 -- or an Out or In_Out parameter (Out_Param set to True). If there is
2266 -- an assignable entity being referenced, then the appropriate flag
2267 -- (Referenced_As_LHS if Out_Param is False, Referenced_As_Out_Parameter
2268 -- if Out_Param is True) is set True, and the other flag set False.
2269
2270 procedure Set_Scope_Is_Transient (V : Boolean := True);
2271 -- Set the flag Is_Transient of the current scope
2272
2273 procedure Set_Size_Info (T1, T2 : Entity_Id);
2274 pragma Inline (Set_Size_Info);
2275 -- Copies the Esize field and Has_Biased_Representation flag from sub(type)
2276 -- entity T2 to (sub)type entity T1. Also copies the Is_Unsigned_Type flag
2277 -- in the fixed-point and discrete cases, and also copies the alignment
2278 -- value from T2 to T1. It does NOT copy the RM_Size field, which must be
2279 -- separately set if this is required to be copied also.
2280
2281 function Scope_Is_Transient return Boolean;
2282 -- True if the current scope is transient
2283
2284 function Static_Boolean (N : Node_Id) return Uint;
2285 -- This function analyzes the given expression node and then resolves it
2286 -- as Standard.Boolean. If the result is static, then Uint_1 or Uint_0 is
2287 -- returned corresponding to the value, otherwise an error message is
2288 -- output and No_Uint is returned.
2289
2290 function Static_Integer (N : Node_Id) return Uint;
2291 -- This function analyzes the given expression node and then resolves it
2292 -- as any integer type. If the result is static, then the value of the
2293 -- universal expression is returned, otherwise an error message is output
2294 -- and a value of No_Uint is returned.
2295
2296 function Statically_Different (E1, E2 : Node_Id) return Boolean;
2297 -- Return True if it can be statically determined that the Expressions
2298 -- E1 and E2 refer to different objects
2299
2300 function Subject_To_Loop_Entry_Attributes (N : Node_Id) return Boolean;
2301 -- Determine whether node N is a loop statement subject to at least one
2302 -- 'Loop_Entry attribute.
2303
2304 function Subprogram_Access_Level (Subp : Entity_Id) return Uint;
2305 -- Return the accessibility level of the view denoted by Subp
2306
2307 function Support_Atomic_Primitives (Typ : Entity_Id) return Boolean;
2308 -- Return True if Typ supports the GCC built-in atomic operations (i.e. if
2309 -- Typ is properly sized and aligned).
2310
2311 procedure Trace_Scope (N : Node_Id; E : Entity_Id; Msg : String);
2312 -- Print debugging information on entry to each unit being analyzed
2313
2314 procedure Transfer_Entities (From : Entity_Id; To : Entity_Id);
2315 -- Move a list of entities from one scope to another, and recompute
2316 -- Is_Public based upon the new scope.
2317
2318 function Type_Access_Level (Typ : Entity_Id) return Uint;
2319 -- Return the accessibility level of Typ
2320
2321 function Type_Without_Stream_Operation
2322 (T : Entity_Id;
2323 Op : TSS_Name_Type := TSS_Null) return Entity_Id;
2324 -- AI05-0161: In Ada 2012, if the restriction No_Default_Stream_Attributes
2325 -- is active then we cannot generate stream subprograms for composite types
2326 -- with elementary subcomponents that lack user-defined stream subprograms.
2327 -- This predicate determines whether a type has such an elementary
2328 -- subcomponent. If Op is TSS_Null, a type that lacks either Read or Write
2329 -- prevents the construction of a composite stream operation. If Op is
2330 -- specified we check only for the given stream operation.
2331
2332 function Unique_Defining_Entity (N : Node_Id) return Entity_Id;
2333 -- Return the entity which represents declaration N, so that different
2334 -- views of the same entity have the same unique defining entity:
2335 -- * entry declaration and entry body
2336 -- * package spec and body
2337 -- * protected type declaration, protected body stub and protected body
2338 -- * private view and full view of a deferred constant
2339 -- * private view and full view of a type
2340 -- * subprogram declaration, subprogram stub and subprogram body
2341 -- * task type declaration, task body stub and task body
2342 -- In other cases, return the defining entity for N.
2343
2344 function Unique_Entity (E : Entity_Id) return Entity_Id;
2345 -- Return the unique entity for entity E, which would be returned by
2346 -- Unique_Defining_Entity if applied to the enclosing declaration of E.
2347
2348 function Unique_Name (E : Entity_Id) return String;
2349 -- Return a unique name for entity E, which could be used to identify E
2350 -- across compilation units.
2351
2352 function Unit_Is_Visible (U : Entity_Id) return Boolean;
2353 -- Determine whether a compilation unit is visible in the current context,
2354 -- because there is a with_clause that makes the unit available. Used to
2355 -- provide better messages on common visiblity errors on operators.
2356
2357 function Universal_Interpretation (Opnd : Node_Id) return Entity_Id;
2358 -- Yields Universal_Integer or Universal_Real if this is a candidate
2359
2360 function Unqualify (Expr : Node_Id) return Node_Id;
2361 pragma Inline (Unqualify);
2362 -- Removes any qualifications from Expr. For example, for T1'(T2'(X)), this
2363 -- returns X. If Expr is not a qualified expression, returns Expr.
2364
2365 function Visible_Ancestors (Typ : Entity_Id) return Elist_Id;
2366 -- [Ada 2012:AI-0125-1]: Collect all the visible parents and progenitors
2367 -- of a type extension or private extension declaration. If the full-view
2368 -- of private parents and progenitors is available then it is used to
2369 -- generate the list of visible ancestors; otherwise their partial
2370 -- view is added to the resulting list.
2371
2372 function Within_Init_Proc return Boolean;
2373 -- Determines if Current_Scope is within an init proc
2374
2375 function Within_Scope (E : Entity_Id; S : Entity_Id) return Boolean;
2376 -- Returns True if entity E is declared within scope S
2377
2378 procedure Wrong_Type (Expr : Node_Id; Expected_Type : Entity_Id);
2379 -- Output error message for incorrectly typed expression. Expr is the node
2380 -- for the incorrectly typed construct (Etype (Expr) is the type found),
2381 -- and Expected_Type is the entity for the expected type. Note that Expr
2382 -- does not have to be a subexpression, anything with an Etype field may
2383 -- be used.
2384
2385 function Yields_Synchronized_Object (Typ : Entity_Id) return Boolean;
2386 -- Determine whether type Typ "yields synchronized object" as specified by
2387 -- SPARK RM 9.1. To qualify as such, a type must be
2388 -- * An array type whose element type yields a synchronized object
2389 -- * A descendant of type Ada.Synchronous_Task_Control.Suspension_Object
2390 -- * A protected type
2391 -- * A record type or type extension without defaulted discriminants
2392 -- whose components are of a type that yields a synchronized object.
2393 -- * A synchronized interface type
2394 -- * A task type
2395
2396 function Yields_Universal_Type (N : Node_Id) return Boolean;
2397 -- Determine whether unanalyzed node N yields a universal type
2398
2399 end Sem_Util;