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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S E M _ U T I L --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2015, Free Software Foundation, Inc. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNAT; see file COPYING3. If not, go to --
-- http://www.gnu.org/licenses for a complete copy of the license. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- Package containing utility procedures used throughout the semantics
with Einfo; use Einfo;
with Exp_Tss; use Exp_Tss;
with Namet; use Namet;
with Opt; use Opt;
with Snames; use Snames;
with Types; use Types;
with Uintp; use Uintp;
with Urealp; use Urealp;
package Sem_Util is
function Abstract_Interface_List (Typ : Entity_Id) return List_Id;
-- Given a type that implements interfaces look for its associated
-- definition node and return its list of interfaces.
procedure Add_Access_Type_To_Process (E : Entity_Id; A : Entity_Id);
-- Add A to the list of access types to process when expanding the
-- freeze node of E.
procedure Add_Block_Identifier (N : Node_Id; Id : out Entity_Id);
-- Given a block statement N, generate an internal E_Block label and make
-- it the identifier of the block. Id denotes the generated entity. If the
-- block already has an identifier, Id returns the entity of its label.
procedure Add_Contract_Item (Prag : Node_Id; Id : Entity_Id);
-- Add pragma Prag to the contract of an entry, a package [body], a
-- subprogram [body] or variable denoted by Id. The following are valid
-- pragmas:
-- Abstract_States
-- Async_Readers
-- Async_Writers
-- Contract_Cases
-- Depends
-- Effective_Reads
-- Effective_Writes
-- Extensions_Visible
-- Global
-- Initial_Condition
-- Initializes
-- Part_Of
-- Postcondition
-- Precondition
-- Refined_Depends
-- Refined_Global
-- Refined_Post
-- Refined_States
-- Test_Case
procedure Add_Global_Declaration (N : Node_Id);
-- These procedures adds a declaration N at the library level, to be
-- elaborated before any other code in the unit. It is used for example
-- for the entity that marks whether a unit has been elaborated. The
-- declaration is added to the Declarations list of the Aux_Decls_Node
-- for the current unit. The declarations are added in the current scope,
-- so the caller should push a new scope as required before the call.
function Address_Integer_Convert_OK (T1, T2 : Entity_Id) return Boolean;
-- Given two types, returns True if we are in Allow_Integer_Address mode
-- and one of the types is (a descendent of) System.Address (and this type
-- is private), and the other type is any integer type.
function Addressable (V : Uint) return Boolean;
function Addressable (V : Int) return Boolean;
pragma Inline (Addressable);
-- Returns True if the value of V is the word size or an addressable factor
-- of the word size (typically 8, 16, 32 or 64).
procedure Aggregate_Constraint_Checks
(Exp : Node_Id;
Check_Typ : Entity_Id);
-- Checks expression Exp against subtype Check_Typ. If Exp is an aggregate
-- and Check_Typ a constrained record type with discriminants, we generate
-- the appropriate discriminant checks. If Exp is an array aggregate then
-- emit the appropriate length checks. If Exp is a scalar type, or a string
-- literal, Exp is changed into Check_Typ'(Exp) to ensure that range checks
-- are performed at run time. Also used for expressions in the argument of
-- 'Update, which shares some of the features of an aggregate.
function Alignment_In_Bits (E : Entity_Id) return Uint;
-- If the alignment of the type or object E is currently known to the
-- compiler, then this function returns the alignment value in bits.
-- Otherwise Uint_0 is returned, indicating that the alignment of the
-- entity is not yet known to the compiler.
procedure Append_Inherited_Subprogram (S : Entity_Id);
-- If the parent of the operation is declared in the visible part of
-- the current scope, the inherited operation is visible even though the
-- derived type that inherits the operation may be completed in the private
-- part of the current package.
procedure Apply_Compile_Time_Constraint_Error
(N : Node_Id;
Msg : String;
Reason : RT_Exception_Code;
Ent : Entity_Id := Empty;
Typ : Entity_Id := Empty;
Loc : Source_Ptr := No_Location;
Rep : Boolean := True;
Warn : Boolean := False);
-- N is a subexpression which will raise constraint error when evaluated
-- at runtime. Msg is a message that explains the reason for raising the
-- exception. The last character is ? if the message is always a warning,
-- even in Ada 95, and is not a ? if the message represents an illegality
-- (because of violation of static expression rules) in Ada 95 (but not
-- in Ada 83). Typically this routine posts all messages at the Sloc of
-- node N. However, if Loc /= No_Location, Loc is the Sloc used to output
-- the message. After posting the appropriate message, and if the flag
-- Rep is set, this routine replaces the expression with an appropriate
-- N_Raise_Constraint_Error node using the given Reason code. This node
-- is then marked as being static if the original node is static, but
-- sets the flag Raises_Constraint_Error, preventing further evaluation.
-- The error message may contain a } or & insertion character. This
-- normally references Etype (N), unless the Ent argument is given
-- explicitly, in which case it is used instead. The type of the raise
-- node that is built is normally Etype (N), but if the Typ parameter
-- is present, this is used instead. Warn is normally False. If it is
-- True then the message is treated as a warning even though it does
-- not end with a ? (this is used when the caller wants to parameterize
-- whether an error or warning is given).
function Async_Readers_Enabled (Id : Entity_Id) return Boolean;
-- Given the entity of an abstract state or a variable, determine whether
-- Id is subject to external property Async_Readers and if it is, the
-- related expression evaluates to True.
function Async_Writers_Enabled (Id : Entity_Id) return Boolean;
-- Given the entity of an abstract state or a variable, determine whether
-- Id is subject to external property Async_Writers and if it is, the
-- related expression evaluates to True.
function Available_Full_View_Of_Component (T : Entity_Id) return Boolean;
-- If at the point of declaration an array type has a private or limited
-- component, several array operations are not avaiable on the type, and
-- the array type is flagged accordingly. If in the immediate scope of
-- the array type the component becomes non-private or non-limited, these
-- operations become avaiable. This can happen if the scopes of both types
-- are open, and the scope of the array is not outside the scope of the
-- component.
procedure Bad_Attribute
(N : Node_Id;
Nam : Name_Id;
Warn : Boolean := False);
-- Called when node N is expected to contain a valid attribute name, and
-- Nam is found instead. If Warn is set True this is a warning, else this
-- is an error.
procedure Bad_Predicated_Subtype_Use
(Msg : String;
N : Node_Id;
Typ : Entity_Id;
Suggest_Static : Boolean := False);
-- This is called when Typ, a predicated subtype, is used in a context
-- which does not allow the use of a predicated subtype. Msg is passed to
-- Error_Msg_FE to output an appropriate message using N as the location,
-- and Typ as the entity. The caller must set up any insertions other than
-- the & for the type itself. Note that if Typ is a generic actual type,
-- then the message will be output as a warning, and a raise Program_Error
-- is inserted using Insert_Action with node N as the insertion point. Node
-- N also supplies the source location for construction of the raise node.
-- If Typ does not have any predicates, the call has no effect. Set flag
-- Suggest_Static when the context warrants an advice on how to avoid the
-- use error.
function Bad_Unordered_Enumeration_Reference
(N : Node_Id;
T : Entity_Id) return Boolean;
-- Node N contains a potentially dubious reference to type T, either an
-- explicit comparison, or an explicit range. This function returns True
-- if the type T is an enumeration type for which No pragma Order has been
-- given, and the reference N is not in the same extended source unit as
-- the declaration of T.
function Build_Actual_Subtype
(T : Entity_Id;
N : Node_Or_Entity_Id) return Node_Id;
-- Build an anonymous subtype for an entity or expression, using the
-- bounds of the entity or the discriminants of the enclosing record.
-- T is the type for which the actual subtype is required, and N is either
-- a defining identifier, or any subexpression.
function Build_Actual_Subtype_Of_Component
(T : Entity_Id;
N : Node_Id) return Node_Id;
-- Determine whether a selected component has a type that depends on
-- discriminants, and build actual subtype for it if so.
function Build_Default_Init_Cond_Call
(Loc : Source_Ptr;
Obj_Id : Entity_Id;
Typ : Entity_Id) return Node_Id;
-- Build a call to the default initial condition procedure of type Typ with
-- Obj_Id as the actual parameter.
procedure Build_Default_Init_Cond_Procedure_Bodies (Priv_Decls : List_Id);
-- Inspect the contents of private declarations Priv_Decls and build the
-- bodies the default initial condition procedures for all types subject
-- to pragma Default_Initial_Condition.
procedure Build_Default_Init_Cond_Procedure_Declaration (Typ : Entity_Id);
-- If private type Typ is subject to pragma Default_Initial_Condition,
-- build the declaration of the procedure which verifies the assumption
-- of the pragma at runtime. The declaration is inserted after the related
-- pragma.
function Build_Default_Subtype
(T : Entity_Id;
N : Node_Id) return Entity_Id;
-- If T is an unconstrained type with defaulted discriminants, build a
-- subtype constrained by the default values, insert the subtype
-- declaration in the tree before N, and return the entity of that
-- subtype. Otherwise, simply return T.
function Build_Discriminal_Subtype_Of_Component
(T : Entity_Id) return Node_Id;
-- Determine whether a record component has a type that depends on
-- discriminants, and build actual subtype for it if so.
procedure Build_Elaboration_Entity (N : Node_Id; Spec_Id : Entity_Id);
-- Given a compilation unit node N, allocate an elaboration counter for
-- the compilation unit, and install it in the Elaboration_Entity field
-- of Spec_Id, the entity for the compilation unit.
procedure Build_Explicit_Dereference
(Expr : Node_Id;
Disc : Entity_Id);
-- AI05-139: Names with implicit dereference. If the expression N is a
-- reference type and the context imposes the corresponding designated
-- type, convert N into N.Disc.all. Such expressions are always over-
-- loaded with both interpretations, and the dereference interpretation
-- carries the name of the reference discriminant.
function Cannot_Raise_Constraint_Error (Expr : Node_Id) return Boolean;
-- Returns True if the expression cannot possibly raise Constraint_Error.
-- The response is conservative in the sense that a result of False does
-- not necessarily mean that CE could be raised, but a response of True
-- means that for sure CE cannot be raised.
procedure Check_Dynamically_Tagged_Expression
(Expr : Node_Id;
Typ : Entity_Id;
Related_Nod : Node_Id);
-- Check wrong use of dynamically tagged expression
procedure Check_Fully_Declared (T : Entity_Id; N : Node_Id);
-- Verify that the full declaration of type T has been seen. If not, place
-- error message on node N. Used in object declarations, type conversions
-- and qualified expressions.
procedure Check_Function_Writable_Actuals (N : Node_Id);
-- (Ada 2012): If the construct N has two or more direct constituents that
-- are names or expressions whose evaluation may occur in an arbitrary
-- order, at least one of which contains a function call with an in out or
-- out parameter, then the construct is legal only if: for each name that
-- is passed as a parameter of mode in out or out to some inner function
-- call C2 (not including the construct N itself), there is no other name
-- anywhere within a direct constituent of the construct C other than
-- the one containing C2, that is known to refer to the same object (RM
-- 6.4.1(6.17/3)).
procedure Check_Implicit_Dereference (N : Node_Id; Typ : Entity_Id);
-- AI05-139-2: Accessors and iterators for containers. This procedure
-- checks whether T is a reference type, and if so it adds an interprettion
-- to N whose type is the designated type of the reference_discriminant.
-- If N is a generalized indexing operation, the interpretation is added
-- both to the corresponding function call, and to the indexing node.
procedure Check_Internal_Protected_Use (N : Node_Id; Nam : Entity_Id);
-- Within a protected function, the current object is a constant, and
-- internal calls to a procedure or entry are illegal. Similarly, other
-- uses of a protected procedure in a renaming or a generic instantiation
-- in the context of a protected function are illegal (AI05-0225).
procedure Check_Later_Vs_Basic_Declarations
(Decls : List_Id;
During_Parsing : Boolean);
-- If During_Parsing is True, check for misplacement of later vs basic
-- declarations in Ada 83. If During_Parsing is False, and the SPARK
-- restriction is set, do the same: although SPARK 95 removes the
-- distinction between initial and later declarative items, the distinction
-- remains in the Examiner (JB01-005). Note that the Examiner does not
-- count package declarations in later declarative items.
procedure Check_Nested_Access (N : Node_Id; Ent : Entity_Id);
-- Check whether Ent denotes an entity declared in an uplevel scope, which
-- is accessed inside a nested procedure, and set the Has_Uplevel_Reference
-- flag accordingly. This is currently only enabled for if on a VM target,
-- or if Opt.Unnest_Subprogram_Mode is active. N is the node for the
-- possible uplevel reference.
procedure Check_No_Hidden_State (Id : Entity_Id);
-- Determine whether object or state Id introduces a hidden state. If this
-- is the case, emit an error.
procedure Check_Potentially_Blocking_Operation (N : Node_Id);
-- N is one of the statement forms that is a potentially blocking
-- operation. If it appears within a protected action, emit warning.
procedure Check_Result_And_Post_State (Subp_Id : Entity_Id);
-- Determine whether the contract of subprogram Subp_Id mentions attribute
-- 'Result and it contains an expression that evaluates differently in pre-
-- and post-state.
procedure Check_Unprotected_Access
(Context : Node_Id;
Expr : Node_Id);
-- Check whether the expression is a pointer to a protected component,
-- and the context is external to the protected operation, to warn against
-- a possible unlocked access to data.
procedure Collect_Interfaces
(T : Entity_Id;
Ifaces_List : out Elist_Id;
Exclude_Parents : Boolean := False;
Use_Full_View : Boolean := True);
-- Ada 2005 (AI-251): Collect whole list of abstract interfaces that are
-- directly or indirectly implemented by T. Exclude_Parents is used to
-- avoid the addition of inherited interfaces to the generated list.
-- Use_Full_View is used to collect the interfaces using the full-view
-- (if available).
procedure Collect_Interface_Components
(Tagged_Type : Entity_Id;
Components_List : out Elist_Id);
-- Ada 2005 (AI-251): Collect all the tag components associated with the
-- secondary dispatch tables of a tagged type.
procedure Collect_Interfaces_Info
(T : Entity_Id;
Ifaces_List : out Elist_Id;
Components_List : out Elist_Id;
Tags_List : out Elist_Id);
-- Ada 2005 (AI-251): Collect all the interfaces associated with T plus
-- the record component and tag associated with each of these interfaces.
-- On exit Ifaces_List, Components_List and Tags_List have the same number
-- of elements, and elements at the same position on these tables provide
-- information on the same interface type.
procedure Collect_Parents
(T : Entity_Id;
List : out Elist_Id;
Use_Full_View : Boolean := True);
-- Collect all the parents of Typ. Use_Full_View is used to collect them
-- using the full-view of private parents (if available).
function Collect_Primitive_Operations (T : Entity_Id) return Elist_Id;
-- Called upon type derivation and extension. We scan the declarative part
-- in which the type appears, and collect subprograms that have one
-- subsidiary subtype of the type. These subprograms can only appear after
-- the type itself.
function Compile_Time_Constraint_Error
(N : Node_Id;
Msg : String;
Ent : Entity_Id := Empty;
Loc : Source_Ptr := No_Location;
Warn : Boolean := False) return Node_Id;
-- This is similar to Apply_Compile_Time_Constraint_Error in that it
-- generates a warning (or error) message in the same manner, but it does
-- not replace any nodes. For convenience, the function always returns its
-- first argument. The message is a warning if the message ends with ?, or
-- we are operating in Ada 83 mode, or the Warn parameter is set to True.
procedure Conditional_Delay (New_Ent, Old_Ent : Entity_Id);
-- Sets the Has_Delayed_Freeze flag of New if the Delayed_Freeze flag of
-- Old is set and Old has no yet been Frozen (i.e. Is_Frozen is false).
function Contains_Refined_State (Prag : Node_Id) return Boolean;
-- Determine whether pragma Prag contains a reference to the entity of an
-- abstract state with a visible refinement. Prag must denote one of the
-- following pragmas:
-- Depends
-- Global
function Copy_Parameter_List (Subp_Id : Entity_Id) return List_Id;
-- Utility to create a parameter profile for a new subprogram spec, when
-- the subprogram has a body that acts as spec. This is done for some cases
-- of inlining, and for private protected ops. Also used to create bodies
-- for stubbed subprograms.
function Copy_Component_List
(R_Typ : Entity_Id;
Loc : Source_Ptr) return List_Id;
-- Copy components from record type R_Typ that come from source. Used to
-- create a new compatible record type. Loc is the source location assigned
-- to the created nodes.
function Corresponding_Generic_Type (T : Entity_Id) return Entity_Id;
-- If a type is a generic actual type, return the corresponding formal in
-- the generic parent unit. There is no direct link in the tree for this
-- attribute, except in the case of formal private and derived types.
-- Possible optimization???
function Corresponding_Spec_Of (Subp_Decl : Node_Id) return Entity_Id;
-- Return the corresponding spec of Subp_Decl when it denotes a body [stub]
-- or the defining entity of subprogram declaration Subp_Decl in all other
-- cases.
function Current_Entity (N : Node_Id) return Entity_Id;
pragma Inline (Current_Entity);
-- Find the currently visible definition for a given identifier, that is to
-- say the first entry in the visibility chain for the Chars of N.
function Current_Entity_In_Scope (N : Node_Id) return Entity_Id;
-- Find whether there is a previous definition for identifier N in the
-- current scope. Because declarations for a scope are not necessarily
-- contiguous (e.g. for packages) the first entry on the visibility chain
-- for N is not necessarily in the current scope.
function Current_Scope return Entity_Id;
-- Get entity representing current scope
function Current_Subprogram return Entity_Id;
-- Returns current enclosing subprogram. If Current_Scope is a subprogram,
-- then that is what is returned, otherwise the Enclosing_Subprogram of the
-- Current_Scope is returned. The returned value is Empty if this is called
-- from a library package which is not within any subprogram.
function Deepest_Type_Access_Level (Typ : Entity_Id) return Uint;
-- Same as Type_Access_Level, except that if the type is the type of an Ada
-- 2012 stand-alone object of an anonymous access type, then return the
-- static accesssibility level of the object. In that case, the dynamic
-- accessibility level of the object may take on values in a range. The low
-- bound of of that range is returned by Type_Access_Level; this function
-- yields the high bound of that range. Also differs from Type_Access_Level
-- in the case of a descendant of a generic formal type (returns Int'Last
-- instead of 0).
function Defining_Entity (N : Node_Id) return Entity_Id;
-- Given a declaration N, returns the associated defining entity. If the
-- declaration has a specification, the entity is obtained from the
-- specification. If the declaration has a defining unit name, then the
-- defining entity is obtained from the defining unit name ignoring any
-- child unit prefixes.
--
-- Iterator loops also have a defining entity, which holds the list of
-- local entities declared during loop expansion. These entities need
-- debugging information, generated through Qualify_Entity_Names, and
-- the loop declaration must be placed in the table Name_Qualify_Units.
function Denotes_Discriminant
(N : Node_Id;
Check_Concurrent : Boolean := False) return Boolean;
-- Returns True if node N is an Entity_Name node for a discriminant. If the
-- flag Check_Concurrent is true, function also returns true when N denotes
-- the discriminal of the discriminant of a concurrent type. This is needed
-- to disable some optimizations on private components of protected types,
-- and constraint checks on entry families constrained by discriminants.
function Denotes_Same_Object (A1, A2 : Node_Id) return Boolean;
-- Detect suspicious overlapping between actuals in a call, when both are
-- writable (RM 2012 6.4.1(6.4/3))
function Denotes_Same_Prefix (A1, A2 : Node_Id) return Boolean;
-- Functions to detect suspicious overlapping between actuals in a call,
-- when one of them is writable. The predicates are those proposed in
-- AI05-0144, to detect dangerous order dependence in complex calls.
-- I would add a parameter Warn which enables more extensive testing of
-- cases as we find appropriate when we are only warning ??? Or perhaps
-- return an indication of (Error, Warn, OK) ???
function Denotes_Variable (N : Node_Id) return Boolean;
-- Returns True if node N denotes a single variable without parentheses
function Depends_On_Discriminant (N : Node_Id) return Boolean;
-- Returns True if N denotes a discriminant or if N is a range, a subtype
-- indication or a scalar subtype where one of the bounds is a
-- discriminant.
function Designate_Same_Unit
(Name1 : Node_Id;
Name2 : Node_Id) return Boolean;
-- Returns True if Name1 and Name2 designate the same unit name; each of
-- these names is supposed to be a selected component name, an expanded
-- name, a defining program unit name or an identifier.
function Dynamic_Accessibility_Level (Expr : Node_Id) return Node_Id;
-- Expr should be an expression of an access type. Builds an integer
-- literal except in cases involving anonymous access types where
-- accessibility levels are tracked at runtime (access parameters and Ada
-- 2012 stand-alone objects).
function Effective_Extra_Accessibility (Id : Entity_Id) return Entity_Id;
-- Same as Einfo.Extra_Accessibility except thtat object renames
-- are looked through.
function Effective_Reads_Enabled (Id : Entity_Id) return Boolean;
-- Given the entity of an abstract state or a variable, determine whether
-- Id is subject to external property Effective_Reads and if it is, the
-- related expression evaluates to True.
function Effective_Writes_Enabled (Id : Entity_Id) return Boolean;
-- Given the entity of an abstract state or a variable, determine whether
-- Id is subject to external property Effective_Writes and if it is, the
-- related expression evaluates to True.
function Enclosing_Comp_Unit_Node (N : Node_Id) return Node_Id;
-- Returns the enclosing N_Compilation_Unit Node that is the root of a
-- subtree containing N.
function Enclosing_CPP_Parent (Typ : Entity_Id) return Entity_Id;
-- Returns the closest ancestor of Typ that is a CPP type.
function Enclosing_Generic_Body
(N : Node_Id) return Node_Id;
-- Returns the Node_Id associated with the innermost enclosing generic
-- body, if any. If none, then returns Empty.
function Enclosing_Generic_Unit
(N : Node_Id) return Node_Id;
-- Returns the Node_Id associated with the innermost enclosing generic
-- unit, if any. If none, then returns Empty.
function Enclosing_Lib_Unit_Entity
(E : Entity_Id := Current_Scope) return Entity_Id;
-- Returns the entity of enclosing library unit node which is the
-- root of the current scope (which must not be Standard_Standard, and the
-- caller is responsible for ensuring this condition) or other specified
-- entity.
function Enclosing_Package (E : Entity_Id) return Entity_Id;
-- Utility function to return the Ada entity of the package enclosing
-- the entity E, if any. Returns Empty if no enclosing package.
function Enclosing_Subprogram (E : Entity_Id) return Entity_Id;
-- Utility function to return the Ada entity of the subprogram enclosing
-- the entity E, if any. Returns Empty if no enclosing subprogram.
procedure Ensure_Freeze_Node (E : Entity_Id);
-- Make sure a freeze node is allocated for entity E. If necessary, build
-- and initialize a new freeze node and set Has_Delayed_Freeze True for E.
procedure Enter_Name (Def_Id : Entity_Id);
-- Insert new name in symbol table of current scope with check for
-- duplications (error message is issued if a conflict is found).
-- Note: Enter_Name is not used for overloadable entities, instead these
-- are entered using Sem_Ch6.Enter_Overloadable_Entity.
function Entity_Of (N : Node_Id) return Entity_Id;
-- Return the entity of N or Empty. If N is a renaming, return the entity
-- of the root renamed object.
procedure Explain_Limited_Type (T : Entity_Id; N : Node_Id);
-- This procedure is called after issuing a message complaining about an
-- inappropriate use of limited type T. If useful, it adds additional
-- continuation lines to the message explaining why type T is limited.
-- Messages are placed at node N.
type Extensions_Visible_Mode is
(Extensions_Visible_None,
-- Extensions_Visible does not yield a mode when SPARK_Mode is off. This
-- value acts as a default in a non-SPARK compilation.
Extensions_Visible_False,
-- A value of "False" signifies that Extensions_Visible is either
-- missing or the pragma is present and the value of its Boolean
-- expression is False.
Extensions_Visible_True);
-- A value of "True" signifies that Extensions_Visible is present and
-- the value of its Boolean expression is True.
function Extensions_Visible_Status
(Id : Entity_Id) return Extensions_Visible_Mode;
-- Given the entity of a subprogram or formal parameter subject to pragma
-- Extensions_Visible, return the Boolean value denoted by the expression
-- of the pragma.
procedure Find_Actual
(N : Node_Id;
Formal : out Entity_Id;
Call : out Node_Id);
-- Determines if the node N is an actual parameter of a function of a
-- procedure call. If so, then Formal points to the entity for the formal
-- (Ekind is E_In_Parameter, E_Out_Parameter, or E_In_Out_Parameter) and
-- Call is set to the node for the corresponding call. If the node N is not
-- an actual parameter then Formal and Call are set to Empty.
function Find_Specific_Type (CW : Entity_Id) return Entity_Id;
-- Find specific type of a class-wide type, and handle the case of an
-- incomplete type coming either from a limited_with clause or from an
-- incomplete type declaration. If resulting type is private return its
-- full view.
function Find_Body_Discriminal
(Spec_Discriminant : Entity_Id) return Entity_Id;
-- Given a discriminant of the record type that implements a task or
-- protected type, return the discriminal of the corresponding discriminant
-- of the actual concurrent type.
function Find_Corresponding_Discriminant
(Id : Node_Id;
Typ : Entity_Id) return Entity_Id;
-- Because discriminants may have different names in a generic unit and in
-- an instance, they are resolved positionally when possible. A reference
-- to a discriminant carries the discriminant that it denotes when it is
-- analyzed. Subsequent uses of this id on a different type denotes the
-- discriminant at the same position in this new type.
function Find_Enclosing_Iterator_Loop (Id : Entity_Id) return Entity_Id;
-- Given an arbitrary entity, try to find the nearest enclosing iterator
-- loop. If such a loop is found, return the entity of its identifier (the
-- E_Loop scope), otherwise return Empty.
function Find_Loop_In_Conditional_Block (N : Node_Id) return Node_Id;
-- Find the nested loop statement in a conditional block. Loops subject to
-- attribute 'Loop_Entry are transformed into blocks. Parts of the original
-- loop are nested within the block.
procedure Find_Overlaid_Entity
(N : Node_Id;
Ent : out Entity_Id;
Off : out Boolean);
-- The node N should be an address representation clause. Determines if
-- the target expression is the address of an entity with an optional
-- offset. If so, set Ent to the entity and, if there is an offset, set
-- Off to True, otherwise to False. If N is not an address representation
-- clause, or if it is not possible to determine that the address is of
-- this form, then set Ent to Empty.
function Find_Parameter_Type (Param : Node_Id) return Entity_Id;
-- Return the type of formal parameter Param as determined by its
-- specification.
-- The following type describes the placement of an arbitrary entity with
-- respect to SPARK visible / hidden state space.
type State_Space_Kind is
(Not_In_Package,
-- An entity is not in the visible, private or body state space when
-- the immediate enclosing construct is not a package.
Visible_State_Space,
-- An entity is in the visible state space when it appears immediately
-- within the visible declarations of a package or when it appears in
-- the visible state space of a nested package which in turn is declared
-- in the visible declarations of an enclosing package:
-- package Pack is
-- Visible_Variable : ...
-- package Nested
-- with Abstract_State => Visible_State
-- is
-- Visible_Nested_Variable : ...
-- end Nested;
-- end Pack;
-- Entities associated with a package instantiation inherit the state
-- space from the instance placement:
-- generic
-- package Gen is
-- Generic_Variable : ...
-- end Gen;
-- with Gen;
-- package Pack is
-- package Inst is new Gen;
-- -- Generic_Variable is in the visible state space of Pack
-- end Pack;
Private_State_Space,
-- An entity is in the private state space when it appears immediately
-- within the private declarations of a package or when it appears in
-- the visible state space of a nested package which in turn is declared
-- in the private declarations of an enclosing package:
-- package Pack is
-- private
-- Private_Variable : ...
-- package Nested
-- with Abstract_State => Private_State
-- is
-- Private_Nested_Variable : ...
-- end Nested;
-- end Pack;
-- The same placement principle applies to package instantiations
Body_State_Space);
-- An entity is in the body state space when it appears immediately
-- within the declarations of a package body or when it appears in the
-- visible state space of a nested package which in turn is declared in
-- the declarations of an enclosing package body:
-- package body Pack is
-- Body_Variable : ...
-- package Nested
-- with Abstract_State => Body_State
-- is
-- Body_Nested_Variable : ...
-- end Nested;
-- end Pack;
-- The same placement principle applies to package instantiations
procedure Find_Placement_In_State_Space
(Item_Id : Entity_Id;
Placement : out State_Space_Kind;
Pack_Id : out Entity_Id);
-- Determine the state space placement of an item. Item_Id denotes the
-- entity of an abstract state, variable or package instantiation.
-- Placement captures the precise placement of the item in the enclosing
-- state space. If the state space is that of a package, Pack_Id denotes
-- its entity, otherwise Pack_Id is Empty.
function Find_Static_Alternative (N : Node_Id) return Node_Id;
-- N is a case statement whose expression is a compile-time value.
-- Determine the alternative chosen, so that the code of non-selected
-- alternatives, and the warnings that may apply to them, are removed.
function First_Actual (Node : Node_Id) return Node_Id;
-- Node is an N_Function_Call or N_Procedure_Call_Statement node. The
-- result returned is the first actual parameter in declaration order
-- (not the order of parameters as they appeared in the source, which
-- can be quite different as a result of the use of named parameters).
-- Empty is returned for a call with no parameters. The procedure for
-- iterating through the actuals in declaration order is to use this
-- function to find the first actual, and then use Next_Actual to obtain
-- the next actual in declaration order. Note that the value returned
-- is always the expression (not the N_Parameter_Association nodes,
-- even if named association is used).
procedure Gather_Components
(Typ : Entity_Id;
Comp_List : Node_Id;
Governed_By : List_Id;
Into : Elist_Id;
Report_Errors : out Boolean);
-- The purpose of this procedure is to gather the valid components in a
-- record type according to the values of its discriminants, in order to
-- validate the components of a record aggregate.
--
-- Typ is the type of the aggregate when its constrained discriminants
-- need to be collected, otherwise it is Empty.
--
-- Comp_List is an N_Component_List node.
--
-- Governed_By is a list of N_Component_Association nodes, where each
-- choice list contains the name of a discriminant and the expression
-- field gives its value. The values of the discriminants governing
-- the (possibly nested) variant parts in Comp_List are found in this
-- Component_Association List.
--
-- Into is the list where the valid components are appended. Note that
-- Into need not be an Empty list. If it's not, components are attached
-- to its tail.
--
-- Report_Errors is set to True if the values of the discriminants are
-- non-static.
--
-- This procedure is also used when building a record subtype. If the
-- discriminant constraint of the subtype is static, the components of the
-- subtype are only those of the variants selected by the values of the
-- discriminants. Otherwise all components of the parent must be included
-- in the subtype for semantic analysis.
function Get_Actual_Subtype (N : Node_Id) return Entity_Id;
-- Given a node for an expression, obtain the actual subtype of the
-- expression. In the case of a parameter where the formal is an
-- unconstrained array or discriminated type, this will be the previously
-- constructed subtype of the actual. Note that this is not quite the
-- "Actual Subtype" of the RM, since it is always a constrained type, i.e.
-- it is the subtype of the value of the actual. The actual subtype is also
-- returned in other cases where it has already been constructed for an
-- object. Otherwise the expression type is returned unchanged, except for
-- the case of an unconstrained array type, where an actual subtype is
-- created, using Insert_Actions if necessary to insert any associated
-- actions.
function Get_Actual_Subtype_If_Available (N : Node_Id) return Entity_Id;
-- This is like Get_Actual_Subtype, except that it never constructs an
-- actual subtype. If an actual subtype is already available, i.e. the
-- Actual_Subtype field of the corresponding entity is set, then it is
-- returned. Otherwise the Etype of the node is returned.
function Get_Body_From_Stub (N : Node_Id) return Node_Id;
-- Return the body node for a stub (subprogram or package)
function Get_Cursor_Type
(Aspect : Node_Id;
Typ : Entity_Id) return Entity_Id;
-- Find Cursor type in scope of formal container Typ, by locating primitive
-- operation First. For use in resolving the other primitive operations
-- of an Iterable type and expanding loops and quantified expressions
-- over formal containers.
function Get_Default_External_Name (E : Node_Or_Entity_Id) return Node_Id;
-- This is used to construct the string literal node representing a
-- default external name, i.e. one that is constructed from the name of an
-- entity, or (in the case of extended DEC import/export pragmas, an
-- identifier provided as the external name. Letters in the name are
-- according to the setting of Opt.External_Name_Default_Casing.
function Get_Enclosing_Object (N : Node_Id) return Entity_Id;
-- If expression N references a part of an object, return this object.
-- Otherwise return Empty. Expression N should have been resolved already.
function Get_Generic_Entity (N : Node_Id) return Entity_Id;
-- Returns the true generic entity in an instantiation. If the name in the
-- instantiation is a renaming, the function returns the renamed generic.
function Get_Incomplete_View_Of_Ancestor (E : Entity_Id) return Entity_Id;
-- Implements the notion introduced ever-so briefly in RM 7.3.1 (5.2/3):
-- in a child unit a derived type is within the derivation class of an
-- ancestor declared in a parent unit, even if there is an intermediate
-- derivation that does not see the full view of that ancestor.
procedure Get_Index_Bounds (N : Node_Id; L, H : out Node_Id);
-- This procedure assigns to L and H respectively the values of the low and
-- high bounds of node N, which must be a range, subtype indication, or the
-- name of a scalar subtype. The result in L, H may be set to Error if
-- there was an earlier error in the range.
function Get_Enum_Lit_From_Pos
(T : Entity_Id;
Pos : Uint;
Loc : Source_Ptr) return Node_Id;
-- This function returns an identifier denoting the E_Enumeration_Literal
-- entity for the specified value from the enumeration type or subtype T.
-- The second argument is the Pos value, which is assumed to be in range.
-- The third argument supplies a source location for constructed nodes
-- returned by this function.
function Get_Iterable_Type_Primitive
(Typ : Entity_Id;
Nam : Name_Id) return Entity_Id;
-- Retrieve one of the primitives First, Next, Has_Element, Element from
-- the value of the Iterable aspect of a formal type.
procedure Get_Library_Unit_Name_String (Decl_Node : Node_Id);
-- Retrieve the fully expanded name of the library unit declared by
-- Decl_Node into the name buffer.
function Get_Name_Entity_Id (Id : Name_Id) return Entity_Id;
pragma Inline (Get_Name_Entity_Id);
-- An entity value is associated with each name in the name table. The
-- Get_Name_Entity_Id function fetches the Entity_Id of this entity, which
-- is the innermost visible entity with the given name. See the body of
-- Sem_Ch8 for further details on handling of entity visibility.
function Get_Name_From_CTC_Pragma (N : Node_Id) return String_Id;
-- Return the Name component of Test_Case pragma N
-- Bad name now that this no longer applies to Contract_Case ???
function Get_Parent_Entity (Unit : Node_Id) return Entity_Id;
-- Get defining entity of parent unit of a child unit. In most cases this
-- is the defining entity of the unit, but for a child instance whose
-- parent needs a body for inlining, the instantiation node of the parent
-- has not yet been rewritten as a package declaration, and the entity has
-- to be retrieved from the Instance_Spec of the unit.
function Get_Pragma_Id (N : Node_Id) return Pragma_Id;
pragma Inline (Get_Pragma_Id);
-- Obtains the Pragma_Id from the Chars field of Pragma_Identifier (N)
procedure Get_Reason_String (N : Node_Id);
-- Recursive routine to analyze reason argument for pragma Warnings. The
-- value of the reason argument is appended to the current string using
-- Store_String_Chars. The reason argument is expected to be a string
-- literal or concatenation of string literals. An error is given for
-- any other form.
function Get_Referenced_Object (N : Node_Id) return Node_Id;
-- Given a node, return the renamed object if the node represents a renamed
-- object, otherwise return the node unchanged. The node may represent an
-- arbitrary expression.
function Get_Renamed_Entity (E : Entity_Id) return Entity_Id;
-- Given an entity for an exception, package, subprogram or generic unit,
-- returns the ultimately renamed entity if this is a renaming. If this is
-- not a renamed entity, returns its argument. It is an error to call this
-- with any other kind of entity.
function Get_Subprogram_Entity (Nod : Node_Id) return Entity_Id;
-- Nod is either a procedure call statement, or a function call, or an
-- accept statement node. This procedure finds the Entity_Id of the related
-- subprogram or entry and returns it, or if no subprogram can be found,
-- returns Empty.
function Get_Subprogram_Body (E : Entity_Id) return Node_Id;
-- Given the entity for a subprogram (E_Function or E_Procedure), return
-- the corresponding N_Subprogram_Body node. If the corresponding body
-- is missing (as for an imported subprogram), return Empty.
function Get_Task_Body_Procedure (E : Entity_Id) return Node_Id;
pragma Inline (Get_Task_Body_Procedure);
-- Given an entity for a task type or subtype, retrieves the
-- Task_Body_Procedure field from the corresponding task type declaration.
function Has_Access_Values (T : Entity_Id) return Boolean;
-- Returns true if type or subtype T is an access type, or has a component
-- (at any recursive level) that is an access type. This is a conservative
-- predicate, if it is not known whether or not T contains access values
-- (happens for generic formals in some cases), then False is returned.
-- Note that tagged types return False. Even though the tag is implemented
-- as an access type internally, this function tests only for access types
-- known to the programmer. See also Has_Tagged_Component.
function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean;
-- Simple predicate to test for defaulted discriminants
type Alignment_Result is (Known_Compatible, Unknown, Known_Incompatible);
-- Result of Has_Compatible_Alignment test, description found below. Note
-- that the values are arranged in increasing order of problematicness.
function Has_Compatible_Alignment
(Obj : Entity_Id;
Expr : Node_Id) return Alignment_Result;
-- Obj is an object entity, and expr is a node for an object reference. If
-- the alignment of the object referenced by Expr is known to be compatible
-- with the alignment of Obj (i.e. is larger or the same), then the result
-- is Known_Compatible. If the alignment of the object referenced by Expr
-- is known to be less than the alignment of Obj, then Known_Incompatible
-- is returned. If neither condition can be reliably established at compile
-- time, then Unknown is returned. This is used to determine if alignment
-- checks are required for address clauses, and also whether copies must
-- be made when objects are passed by reference.
--
-- Note: Known_Incompatible does not mean that at run time the alignment
-- of Expr is known to be wrong for Obj, just that it can be determined
-- that alignments have been explicitly or implicitly specified which are
-- incompatible (whereas Unknown means that even this is not known). The
-- appropriate reaction of a caller to Known_Incompatible is to treat it as
-- Unknown, but issue a warning that there may be an alignment error.
function Has_Declarations (N : Node_Id) return Boolean;
-- Determines if the node can have declarations
function Has_Denormals (E : Entity_Id) return Boolean;
-- Determines if the floating-point type E supports denormal numbers.
-- Returns False if E is not a floating-point type.
function Has_Discriminant_Dependent_Constraint
(Comp : Entity_Id) return Boolean;
-- Returns True if and only if Comp has a constrained subtype that depends
-- on a discriminant.
function Has_Infinities (E : Entity_Id) return Boolean;
-- Determines if the range of the floating-point type E includes
-- infinities. Returns False if E is not a floating-point type.
function Has_Interfaces
(T : Entity_Id;
Use_Full_View : Boolean := True) return Boolean;
-- Where T is a concurrent type or a record type, returns true if T covers
-- any abstract interface types. In case of private types the argument
-- Use_Full_View controls if the check is done using its full view (if
-- available).
function Has_No_Obvious_Side_Effects (N : Node_Id) return Boolean;
-- This is a simple minded function for determining whether an expression
-- has no obvious side effects. It is used only for determining whether
-- warnings are needed in certain situations, and is not guaranteed to
-- be accurate in either direction. Exceptions may mean an expression
-- does in fact have side effects, but this may be ignored and True is
-- returned, or a complex expression may in fact be side effect free
-- but we don't recognize it here and return False. The Side_Effect_Free
-- routine in Remove_Side_Effects is much more extensive and perhaps could
-- be shared, so that this routine would be more accurate.
function Has_Null_Exclusion (N : Node_Id) return Boolean;
-- Determine whether node N has a null exclusion
function Has_Overriding_Initialize (T : Entity_Id) return Boolean;
-- Predicate to determine whether a controlled type has a user-defined
-- Initialize primitive (and, in Ada 2012, whether that primitive is
-- non-null), which causes the type to not have preelaborable
-- initialization.
function Has_Preelaborable_Initialization (E : Entity_Id) return Boolean;
-- Return True iff type E has preelaborable initialization as defined in
-- Ada 2005 (see AI-161 for details of the definition of this attribute).
function Has_Private_Component (Type_Id : Entity_Id) return Boolean;
-- Check if a type has a (sub)component of a private type that has not
-- yet received a full declaration.
function Has_Signed_Zeros (E : Entity_Id) return Boolean;
-- Determines if the floating-point type E supports signed zeros.
-- Returns False if E is not a floating-point type.
function Has_Significant_Contract (Subp_Id : Entity_Id) return Boolean;
-- Determine whether subprogram [body] Subp_Id has a significant contract.
-- All subprograms have a N_Contract node, but this does not mean that the
-- contract is useful.
function Has_Static_Array_Bounds (Typ : Node_Id) return Boolean;
-- Return whether an array type has static bounds
function Has_Stream (T : Entity_Id) return Boolean;
-- Tests if type T is derived from Ada.Streams.Root_Stream_Type, or in the
-- case of a composite type, has a component for which this predicate is
-- True, and if so returns True. Otherwise a result of False means that
-- there is no Stream type in sight. For a private type, the test is
-- applied to the underlying type (or returns False if there is no
-- underlying type).
function Has_Suffix (E : Entity_Id; Suffix : Character) return Boolean;
-- Returns true if the last character of E is Suffix. Used in Assertions.
function Add_Suffix (E : Entity_Id; Suffix : Character) return Name_Id;
-- Returns the name of E adding Suffix
function Remove_Suffix (E : Entity_Id; Suffix : Character) return Name_Id;
-- Returns the name of E without Suffix
function Has_Tagged_Component (Typ : Entity_Id) return Boolean;
-- Returns True if Typ is a composite type (array or record) which is
-- either itself a tagged type, or has a component (recursively) which is
-- a tagged type. Returns False for non-composite type, or if no tagged
-- component is present. This function is used to check if "=" has to be
-- expanded into a bunch component comparisons.
function Has_Volatile_Component (Typ : Entity_Id) return Boolean;
-- Given an arbitrary type, determine whether it contains at least one
-- volatile component.
function Implementation_Kind (Subp : Entity_Id) return Name_Id;
-- Subp is a subprogram marked with pragma Implemented. Return the specific
-- implementation requirement which the pragma imposes. The return value is
-- either Name_By_Any, Name_By_Entry or Name_By_Protected_Procedure.
function Implements_Interface
(Typ_Ent : Entity_Id;
Iface_Ent : Entity_Id;
Exclude_Parents : Boolean := False) return Boolean;
-- Returns true if the Typ_Ent implements interface Iface_Ent
function In_Assertion_Expression_Pragma (N : Node_Id) return Boolean;
-- Determine whether an arbitrary node appears in a pragma that acts as an
-- assertion expression. See Sem_Prag for the list of qualifying pragmas.
function In_Instance return Boolean;
-- Returns True if the current scope is within a generic instance
function In_Instance_Body return Boolean;
-- Returns True if current scope is within the body of an instance, where
-- several semantic checks (e.g. accessibility checks) are relaxed.
function In_Instance_Not_Visible return Boolean;
-- Returns True if current scope is with the private part or the body of
-- an instance. Other semantic checks are suppressed in this context.
function In_Instance_Visible_Part return Boolean;
-- Returns True if current scope is within the visible part of a package
-- instance, where several additional semantic checks apply.
function In_Package_Body return Boolean;
-- Returns True if current scope is within a package body
function In_Parameter_Specification (N : Node_Id) return Boolean;
-- Returns True if node N belongs to a parameter specification
function In_Pragma_Expression (N : Node_Id; Nam : Name_Id) return Boolean;
-- Returns true if the expression N occurs within a pragma with name Nam
function In_Reverse_Storage_Order_Object (N : Node_Id) return Boolean;
-- Returns True if N denotes a component or subcomponent in a record or
-- array that has Reverse_Storage_Order.
function In_Subprogram_Or_Concurrent_Unit return Boolean;
-- Determines if the current scope is within a subprogram compilation unit
-- (inside a subprogram declaration, subprogram body, or generic subprogram
-- declaration) or within a task or protected body. The test is for
-- appearing anywhere within such a construct (that is it does not need
-- to be directly within).
function In_Visible_Part (Scope_Id : Entity_Id) return Boolean;
-- Determine whether a declaration occurs within the visible part of a
-- package specification. The package must be on the scope stack, and the
-- corresponding private part must not.
function Incomplete_Or_Partial_View (Id : Entity_Id) return Entity_Id;
-- Given the entity of a constant or a type, retrieve the incomplete or
-- partial view of the same entity. Note that Id may not have a partial
-- view in which case the function returns Empty.
procedure Inherit_Default_Init_Cond_Procedure (Typ : Entity_Id);
-- Inherit the default initial condition procedure from the parent type of
-- derived type Typ.
procedure Inherit_Rep_Item_Chain (Typ : Entity_Id; From_Typ : Entity_Id);
-- Inherit the rep item chain of type From_Typ without clobbering any
-- existing rep items on Typ's chain. Typ is the destination type.
procedure Inherit_Subprogram_Contract
(Subp : Entity_Id;
From_Subp : Entity_Id);
-- Inherit relevant contract items from source subprogram From_Subp. Subp
-- denotes the destination subprogram. The inherited items are:
-- Extensions_Visible
-- ??? it would be nice if this routine handles Pre'Class and Post'Class
procedure Insert_Explicit_Dereference (N : Node_Id);
-- In a context that requires a composite or subprogram type and where a
-- prefix is an access type, rewrite the access type node N (which is the
-- prefix, e.g. of an indexed component) as an explicit dereference.
procedure Inspect_Deferred_Constant_Completion (Decls : List_Id);
-- Examine all deferred constants in the declaration list Decls and check
-- whether they have been completed by a full constant declaration or an
-- Import pragma. Emit the error message if that is not the case.
procedure Install_Generic_Formals (Subp_Id : Entity_Id);
-- Install both the generic formal parameters and the formal parameters of
-- generic subprogram Subp_Id into visibility.
function Is_Actual_Out_Parameter (N : Node_Id) return Boolean;
-- Determines if N is an actual parameter of out mode in a subprogram call
function Is_Actual_Parameter (N : Node_Id) return Boolean;
-- Determines if N is an actual parameter in a subprogram call
function Is_Actual_Tagged_Parameter (N : Node_Id) return Boolean;
-- Determines if N is an actual parameter of a formal of tagged type in a
-- subprogram call.
function Is_Aliased_View (Obj : Node_Id) return Boolean;
-- Determine if Obj is an aliased view, i.e. the name of an object to which
-- 'Access or 'Unchecked_Access can apply. Note that this routine uses the
-- rules of the language, it does not take into account the restriction
-- No_Implicit_Aliasing, so it can return True if the restriction is active
-- and Obj violates the restriction. The caller is responsible for calling
-- Restrict.Check_No_Implicit_Aliasing if True is returned, but there is a
-- requirement for obeying the restriction in the call context.
function Is_Ancestor_Package
(E1 : Entity_Id;
E2 : Entity_Id) return Boolean;
-- Determine whether package E1 is an ancestor of E2
function Is_Atomic_Object (N : Node_Id) return Boolean;
-- Determines if the given node denotes an atomic object in the sense of
-- the legality checks described in RM C.6(12).
function Is_Attribute_Result (N : Node_Id) return Boolean;
-- Determine whether node N denotes attribute 'Result
function Is_Body_Or_Package_Declaration (N : Node_Id) return Boolean;
-- Determine whether node N denotes a body or a package declaration
function Is_Bounded_String (T : Entity_Id) return Boolean;
-- True if T is a bounded string type. Used to make sure "=" composes
-- properly for bounded string types.
function Is_Constant_Bound (Exp : Node_Id) return Boolean;
-- Exp is the expression for an array bound. Determines whether the
-- bound is a compile-time known value, or a constant entity, or an
-- enumeration literal, or an expression composed of constant-bound
-- subexpressions which are evaluated by means of standard operators.
function Is_Container_Element (Exp : Node_Id) return Boolean;
-- This routine recognizes expressions that denote an element of one of
-- the predefined containers, when the source only contains an indexing
-- operation and an implicit dereference is inserted by the compiler.
-- In the absence of this optimization, the indexing creates a temporary
-- controlled cursor that sets the tampering bit of the container, and
-- restricts the use of the convenient notation C (X) to contexts that
-- do not check the tampering bit (e.g. C.Include (X, C (Y)). Exp is an
-- explicit dereference. The transformation applies when it has the form
-- F (X).Discr.all.
function Is_Controlling_Limited_Procedure
(Proc_Nam : Entity_Id) return Boolean;
-- Ada 2005 (AI-345): Determine whether Proc_Nam is a primitive procedure
-- of a limited interface with a controlling first parameter.
function Is_CPP_Constructor_Call (N : Node_Id) return Boolean;
-- Returns True if N is a call to a CPP constructor
function Is_Child_Or_Sibling
(Pack_1 : Entity_Id;
Pack_2 : Entity_Id) return Boolean;
-- Determine the following relations between two arbitrary packages:
-- 1) One package is the parent of a child package
-- 2) Both packages are siblings and share a common parent
function Is_Concurrent_Interface (T : Entity_Id) return Boolean;
-- First determine whether type T is an interface and then check whether
-- it is of protected, synchronized or task kind.
function Is_Declaration (N : Node_Id) return Boolean;
-- Determine whether arbitrary node N denotes a declaration
function Is_Delegate (T : Entity_Id) return Boolean;
-- Returns true if type T represents a delegate. A Delegate is the CIL
-- object used to represent access-to-subprogram types. This is only
-- relevant to CIL, will always return false for other targets.
function Is_Dependent_Component_Of_Mutable_Object
(Object : Node_Id) return Boolean;
-- Returns True if Object is the name of a subcomponent that depends on
-- discriminants of a variable whose nominal subtype is unconstrained and
-- not indefinite, and the variable is not aliased. Otherwise returns
-- False. The nodes passed to this function are assumed to denote objects.
function Is_Dereferenced (N : Node_Id) return Boolean;
-- N is a subexpression node of an access type. This function returns true
-- if N appears as the prefix of a node that does a dereference of the
-- access value (selected/indexed component, explicit dereference or a
-- slice), and false otherwise.
function Is_Descendent_Of (T1 : Entity_Id; T2 : Entity_Id) return Boolean;
-- Returns True if type T1 is a descendent of type T2, and false otherwise.
-- This is the RM definition, a type is a descendent of another type if it
-- is the same type or is derived from a descendent of the other type.
function Is_Effectively_Volatile (Id : Entity_Id) return Boolean;
-- The SPARK property "effectively volatile" applies to both types and
-- objects. To qualify as such, an entity must be either volatile or be
-- (of) an array type subject to aspect Volatile_Components.
function Is_Effectively_Volatile_Object (N : Node_Id) return Boolean;
-- Determine whether an arbitrary node denotes an effectively volatile
-- object.
function Is_Expression_Function (Subp : Entity_Id) return Boolean;
-- Predicate to determine whether a scope entity comes from a rewritten
-- expression function call, and should be inlined unconditionally. Also
-- used to determine that such a call does not constitute a freeze point.
function Is_EVF_Expression (N : Node_Id) return Boolean;
-- Determine whether node N denotes a reference to a formal parameter of
-- a specific tagged type whose related subprogram is subject to pragma
-- Extensions_Visible with value "False". Several other constructs fall
-- under this category:
-- 1) A qualified expression whose operand is EVF
-- 2) A type conversion whose operand is EVF
-- 3) An if expression with at least one EVF dependent_expression
-- 4) A case expression with at least one EVF dependent_expression
function Is_False (U : Uint) return Boolean;
pragma Inline (Is_False);
-- The argument is a Uint value which is the Boolean'Pos value of a Boolean
-- operand (i.e. is either 0 for False, or 1 for True). This function tests
-- if it is False (i.e. zero).
function Is_Fixed_Model_Number (U : Ureal; T : Entity_Id) return Boolean;
-- Returns True iff the number U is a model number of the fixed-point type
-- T, i.e. if it is an exact multiple of Small.
function Is_Fully_Initialized_Type (Typ : Entity_Id) return Boolean;
-- Typ is a type entity. This function returns true if this type is fully
-- initialized, meaning that an object of the type is fully initialized.
-- Note that initialization resulting from use of pragma Normalized_Scalars
-- does not count. Note that this is only used for the purpose of issuing
-- warnings for objects that are potentially referenced uninitialized. This
-- means that the result returned is not crucial, but should err on the
-- side of thinking things are fully initialized if it does not know.
function Is_Inherited_Operation (E : Entity_Id) return Boolean;
-- E is a subprogram. Return True is E is an implicit operation inherited
-- by a derived type declaration.
function Is_Inherited_Operation_For_Type
(E : Entity_Id;
Typ : Entity_Id) return Boolean;
-- E is a subprogram. Return True is E is an implicit operation inherited
-- by the derived type declaration for type Typ.
function Is_Iterator (Typ : Entity_Id) return Boolean;
-- AI05-0139-2: Check whether Typ is one of the predefined interfaces in
-- Ada.Iterator_Interfaces, or it is derived from one.
type Is_LHS_Result is (Yes, No, Unknown);
function Is_LHS (N : Node_Id) return Is_LHS_Result;
-- Returns Yes if N is definitely used as Name in an assignment statement.
-- Returns No if N is definitely NOT used as a Name in an assignment
-- statement. Returns Unknown if we can't tell at this stage (happens in
-- the case where we don't know the type of N yet, and we have something
-- like N.A := 3, where this counts as N being used on the left side of
-- an assignment only if N is not an access type. If it is an access type
-- then it is N.all.A that is assigned, not N.
function Is_Library_Level_Entity (E : Entity_Id) return Boolean;
-- A library-level declaration is one that is accessible from Standard,
-- i.e. a library unit or an entity declared in a library package.
function Is_Limited_Class_Wide_Type (Typ : Entity_Id) return Boolean;
-- Determine whether a given type is a limited class-wide type, in which
-- case it needs a Master_Id, because extensions of its designated type
-- may include task components. A class-wide type that comes from a
-- limited view must be treated in the same way.
function Is_Local_Variable_Reference (Expr : Node_Id) return Boolean;
-- Determines whether Expr is a reference to a variable or IN OUT mode
-- parameter of the current enclosing subprogram.
-- Why are OUT parameters not considered here ???
function Is_Object_Reference (N : Node_Id) return Boolean;
-- Determines if the tree referenced by N represents an object. Both
-- variable and constant objects return True (compare Is_Variable).
function Is_OK_Variable_For_Out_Formal (AV : Node_Id) return Boolean;
-- Used to test if AV is an acceptable formal for an OUT or IN OUT formal.
-- Note that the Is_Variable function is not quite the right test because
-- this is a case in which conversions whose expression is a variable (in
-- the Is_Variable sense) with an untagged type target are considered view
-- conversions and hence variables.
function Is_Partially_Initialized_Type
(Typ : Entity_Id;
Include_Implicit : Boolean := True) return Boolean;
-- Typ is a type entity. This function returns true if this type is partly
-- initialized, meaning that an object of the type is at least partly
-- initialized (in particular in the record case, that at least one
-- component has an initialization expression). Note that initialization
-- resulting from the use of pragma Normalized_Scalars does not count.
-- Include_Implicit controls whether implicit initialization of access
-- values to null, and of discriminant values, is counted as making the
-- type be partially initialized. For the default setting of True, these
-- implicit cases do count, and discriminated types or types containing
-- access values not explicitly initialized will return True. Otherwise
-- if Include_Implicit is False, these cases do not count as making the
-- type be partially initialized.
function Is_Potentially_Unevaluated (N : Node_Id) return Boolean;
-- Predicate to implement definition given in RM 6.1.1 (20/3)
function Is_Potentially_Persistent_Type (T : Entity_Id) return Boolean;
-- Determines if type T is a potentially persistent type. A potentially
-- persistent type is defined (recursively) as a scalar type, an untagged
-- record whose components are all of a potentially persistent type, or an
-- array with all static constraints whose component type is potentially
-- persistent. A private type is potentially persistent if the full type
-- is potentially persistent.
function Is_Protected_Self_Reference (N : Node_Id) return Boolean;
-- Return True if node N denotes a protected type name which represents
-- the current instance of a protected object according to RM 9.4(21/2).
function Is_RCI_Pkg_Spec_Or_Body (Cunit : Node_Id) return Boolean;
-- Return True if a compilation unit is the specification or the
-- body of a remote call interface package.
function Is_Remote_Access_To_Class_Wide_Type (E : Entity_Id) return Boolean;
-- Return True if E is a remote access-to-class-wide type
function Is_Remote_Access_To_Subprogram_Type (E : Entity_Id) return Boolean;
-- Return True if E is a remote access to subprogram type
function Is_Remote_Call (N : Node_Id) return Boolean;
-- Return True if N denotes a potentially remote call
function Is_Renamed_Entry (Proc_Nam : Entity_Id) return Boolean;
-- Return True if Proc_Nam is a procedure renaming of an entry
function Is_Reversible_Iterator (Typ : Entity_Id) return Boolean;
-- AI05-0139-2: Check whether Typ is derived from the predefined interface
-- Ada.Iterator_Interfaces.Reversible_Iterator.
function Is_Selector_Name (N : Node_Id) return Boolean;
-- Given an N_Identifier node N, determines if it is a Selector_Name.
-- As described in Sinfo, Selector_Names are special because they
-- represent use of the N_Identifier node for a true identifier, when
-- normally such nodes represent a direct name.
function Is_SPARK_05_Initialization_Expr (N : Node_Id) return Boolean;
-- Determines if the tree referenced by N represents an initialization
-- expression in SPARK 2005, suitable for initializing an object in an
-- object declaration.
function Is_SPARK_05_Object_Reference (N : Node_Id) return Boolean;
-- Determines if the tree referenced by N represents an object in SPARK
-- 2005. This differs from Is_Object_Reference in that only variables,
-- constants, formal parameters, and selected_components of those are
-- valid objects in SPARK 2005.
function Is_Specific_Tagged_Type (Typ : Entity_Id) return Boolean;
-- Determine whether an arbitrary [private] type is specifically tagged
function Is_Statement (N : Node_Id) return Boolean;
pragma Inline (Is_Statement);
-- Check if the node N is a statement node. Note that this includes
-- the case of procedure call statements (unlike the direct use of
-- the N_Statement_Other_Than_Procedure_Call subtype from Sinfo).
-- Note that a label is *not* a statement, and will return False.
function Is_Subprogram_Stub_Without_Prior_Declaration
(N : Node_Id) return Boolean;
-- Return True if N is a subprogram stub with no prior subprogram
-- declaration.
function Is_Synchronized_Tagged_Type (E : Entity_Id) return Boolean;
-- Returns True if E is a synchronized tagged type (AARM 3.9.4 (6/2))
function Is_Transfer (N : Node_Id) return Boolean;
-- Returns True if the node N is a statement which is known to cause an
-- unconditional transfer of control at runtime, i.e. the following
-- statement definitely will not be executed.
function Is_True (U : Uint) return Boolean;
pragma Inline (Is_True);
-- The argument is a Uint value which is the Boolean'Pos value of a Boolean
-- operand (i.e. is either 0 for False, or 1 for True). This function tests
-- if it is True (i.e. non-zero).
function Is_Unchecked_Conversion_Instance (Id : Entity_Id) return Boolean;
-- Determine whether an arbitrary entity denotes an instance of function
-- Ada.Unchecked_Conversion.
function Is_Universal_Numeric_Type (T : Entity_Id) return Boolean;
pragma Inline (Is_Universal_Numeric_Type);
-- True if T is Universal_Integer or Universal_Real
function Is_Value_Type (T : Entity_Id) return Boolean;
-- Returns true if type T represents a value type. This is only relevant to
-- CIL, will always return false for other targets. A value type is a CIL
-- object that is accessed directly, as opposed to the other CIL objects
-- that are accessed through managed pointers.
function Is_Variable_Size_Array (E : Entity_Id) return Boolean;
-- Returns true if E has variable size components
function Is_Variable_Size_Record (E : Entity_Id) return Boolean;
-- Returns true if E has variable size components
function Is_Variable
(N : Node_Id;
Use_Original_Node : Boolean := True) return Boolean;
-- Determines if the tree referenced by N represents a variable, i.e. can
-- appear on the left side of an assignment. There is one situation (formal
-- parameters) in which untagged type conversions are also considered
-- variables, but Is_Variable returns False for such cases, since it has
-- no knowledge of the context. Note that this is the point at which
-- Assignment_OK is checked, and True is returned for any tree thus marked.
-- Use_Original_Node is used to perform the test on Original_Node (N). By
-- default is True since this routine is commonly invoked as part of the
-- semantic analysis and it must not be disturbed by the rewriten nodes.
function Is_Visibly_Controlled (T : Entity_Id) return Boolean;
-- Check whether T is derived from a visibly controlled type. This is true
-- if the root type is declared in Ada.Finalization. If T is derived
-- instead from a private type whose full view is controlled, an explicit
-- Initialize/Adjust/Finalize subprogram does not override the inherited
-- one.
function Is_Volatile_Object (N : Node_Id) return Boolean;
-- Determines if the given node denotes an volatile object in the sense of
-- the legality checks described in RM C.6(12). Note that the test here is
-- for something actually declared as volatile, not for an object that gets
-- treated as volatile (see Einfo.Treat_As_Volatile).
function Itype_Has_Declaration (Id : Entity_Id) return Boolean;
-- Applies to Itypes. True if the Itype is attached to a declaration for
-- the type through its Parent field, which may or not be present in the
-- tree.
procedure Kill_Current_Values (Last_Assignment_Only : Boolean := False);
-- This procedure is called to clear all constant indications from all
-- entities in the current scope and in any parent scopes if the current
-- scope is a block or a package (and that recursion continues to the top
-- scope that is not a block or a package). This is used when the
-- sequential flow-of-control assumption is violated (occurrence of a
-- label, head of a loop, or start of an exception handler). The effect of
-- the call is to clear the Current_Value field (but we do not need to
-- clear the Is_True_Constant flag, since that only gets reset if there
-- really is an assignment somewhere in the entity scope). This procedure
-- also calls Kill_All_Checks, since this is a special case of needing to
-- forget saved values. This procedure also clears the Is_Known_Null and
-- Is_Known_Non_Null and Is_Known_Valid flags in variables, constants or
-- parameters since these are also not known to be trustable any more.
--
-- The Last_Assignment_Only flag is set True to clear only Last_Assignment
-- fields and leave other fields unchanged. This is used when we encounter
-- an unconditional flow of control change (return, goto, raise). In such
-- cases we don't need to clear the current values, since it may be that
-- the flow of control change occurs in a conditional context, and if it
-- is not taken, then it is just fine to keep the current values. But the
-- Last_Assignment field is different, if we have a sequence assign-to-v,
-- conditional-return, assign-to-v, we do not want to complain that the
-- second assignment clobbers the first.
procedure Kill_Current_Values
(Ent : Entity_Id;
Last_Assignment_Only : Boolean := False);
-- This performs the same processing as described above for the form with
-- no argument, but for the specific entity given. The call has no effect
-- if the entity Ent is not for an object. Last_Assignment_Only has the
-- same meaning as for the call with no Ent.
procedure Kill_Size_Check_Code (E : Entity_Id);
-- Called when an address clause or pragma Import is applied to an entity.
-- If the entity is a variable or a constant, and size check code is
-- present, this size check code is killed, since the object will not be
-- allocated by the program.
function Known_To_Be_Assigned (N : Node_Id) return Boolean;
-- The node N is an entity reference. This function determines whether the
-- reference is for sure an assignment of the entity, returning True if
-- so. This differs from May_Be_Lvalue in that it defaults in the other
-- direction. Cases which may possibly be assignments but are not known to
-- be may return True from May_Be_Lvalue, but False from this function.
function Last_Source_Statement (HSS : Node_Id) return Node_Id;
-- HSS is a handled statement sequence. This function returns the last
-- statement in Statements (HSS) that has Comes_From_Source set. If no
-- such statement exists, Empty is returned.
function Matching_Static_Array_Bounds
(L_Typ : Node_Id;
R_Typ : Node_Id) return Boolean;
-- L_Typ and R_Typ are two array types. Returns True when they have the
-- same number of dimensions, and the same static bounds for each index
-- position.
procedure Mark_Coextensions (Context_Nod : Node_Id; Root_Nod : Node_Id);
-- Given a node which designates the context of analysis and an origin in
-- the tree, traverse from Root_Nod and mark all allocators as either
-- dynamic or static depending on Context_Nod. Any incorrect marking is
-- cleaned up during resolution.
function May_Be_Lvalue (N : Node_Id) return Boolean;
-- Determines if N could be an lvalue (e.g. an assignment left hand side).
-- An lvalue is defined as any expression which appears in a context where
-- a name is required by the syntax, and the identity, rather than merely
-- the value of the node is needed (for example, the prefix of an Access
-- attribute is in this category). Note that, as implied by the name, this
-- test is conservative. If it cannot be sure that N is NOT an lvalue, then
-- it returns True. It tries hard to get the answer right, but it is hard
-- to guarantee this in all cases. Note that it is more possible to give
-- correct answer if the tree is fully analyzed.
function Needs_One_Actual (E : Entity_Id) return Boolean;
-- Returns True if a function has defaults for all but its first
-- formal. Used in Ada 2005 mode to solve the syntactic ambiguity that
-- results from an indexing of a function call written in prefix form.
function New_Copy_List_Tree (List : List_Id) return List_Id;
-- Copy recursively an analyzed list of nodes. Uses New_Copy_Tree defined
-- below. As for New_Copy_Tree, it is illegal to attempt to copy extended
-- nodes (entities) either directly or indirectly using this function.
function New_Copy_Tree
(Source : Node_Id;
Map : Elist_Id := No_Elist;
New_Sloc : Source_Ptr := No_Location;
New_Scope : Entity_Id := Empty) return Node_Id;
-- Given a node that is the root of a subtree, Copy_Tree copies the entire
-- syntactic subtree, including recursively any descendents whose parent
-- field references a copied node (descendents not linked to a copied node
-- by the parent field are not copied, instead the copied tree references
-- the same descendent as the original in this case, which is appropriate
-- for non-syntactic fields such as Etype). The parent pointers in the
-- copy are properly set. Copy_Tree (Empty/Error) returns Empty/Error.
-- The one exception to the rule of not copying semantic fields is that
-- any implicit types attached to the subtree are duplicated, so that
-- the copy contains a distinct set of implicit type entities. Thus this
-- function is used when it is necessary to duplicate an analyzed tree,
-- declared in the same or some other compilation unit. This function is
-- declared here rather than in atree because it uses semantic information
-- in particular concerning the structure of itypes and the generation of
-- public symbols.
-- The Map argument, if set to a non-empty Elist, specifies a set of
-- mappings to be applied to entities in the tree. The map has the form:
--
-- old entity 1
-- new entity to replace references to entity 1
-- old entity 2
-- new entity to replace references to entity 2
-- ...
--
-- The call destroys the contents of Map in this case
--
-- The parameter New_Sloc, if set to a value other than No_Location, is
-- used as the Sloc value for all nodes in the new copy. If New_Sloc is
-- set to its default value No_Location, then the Sloc values of the
-- nodes in the copy are simply copied from the corresponding original.
--
-- The Comes_From_Source indication is unchanged if New_Sloc is set to
-- the default No_Location value, but is reset if New_Sloc is given, since
-- in this case the result clearly is neither a source node or an exact
-- copy of a source node.
--
-- The parameter New_Scope, if set to a value other than Empty, is the
-- value to use as the Scope for any Itypes that are copied. The most
-- typical value for this parameter, if given, is Current_Scope.
function New_External_Entity
(Kind : Entity_Kind;
Scope_Id : Entity_Id;
Sloc_Value : Source_Ptr;
Related_Id : Entity_Id;
Suffix : Character;
Suffix_Index : Nat := 0;
Prefix : Character := ' ') return Entity_Id;
-- This function creates an N_Defining_Identifier node for an internal
-- created entity, such as an implicit type or subtype, or a record
-- initialization procedure. The entity name is constructed with a call
-- to New_External_Name (Related_Id, Suffix, Suffix_Index, Prefix), so
-- that the generated name may be referenced as a public entry, and the
-- Is_Public flag is set if needed (using Set_Public_Status). If the
-- entity is for a type or subtype, the size/align fields are initialized
-- to unknown (Uint_0).
function New_Internal_Entity
(Kind : Entity_Kind;
Scope_Id : Entity_Id;
Sloc_Value : Source_Ptr;
Id_Char : Character) return Entity_Id;
-- This function is similar to New_External_Entity, except that the
-- name is constructed by New_Internal_Name (Id_Char). This is used
-- when the resulting entity does not have to be referenced as a
-- public entity (and in this case Is_Public is not set).
procedure Next_Actual (Actual_Id : in out Node_Id);
pragma Inline (Next_Actual);
-- Next_Actual (N) is equivalent to N := Next_Actual (N). Note that we
-- inline this procedural form, but not the functional form that follows.
function Next_Actual (Actual_Id : Node_Id) return Node_Id;
-- Find next actual parameter in declaration order. As described for
-- First_Actual, this is the next actual in the declaration order, not
-- the call order, so this does not correspond to simply taking the
-- next entry of the Parameter_Associations list. The argument is an
-- actual previously returned by a call to First_Actual or Next_Actual.
-- Note that the result produced is always an expression, not a parameter
-- association node, even if named notation was used.
procedure Normalize_Actuals
(N : Node_Id;
S : Entity_Id;
Report : Boolean;
Success : out Boolean);
-- Reorders lists of actuals according to names of formals, value returned
-- in Success indicates success of reordering. For more details, see body.
-- Errors are reported only if Report is set to True.
procedure Note_Possible_Modification (N : Node_Id; Sure : Boolean);
-- This routine is called if the sub-expression N maybe the target of
-- an assignment (e.g. it is the left side of an assignment, used as
-- an out parameters, or used as prefixes of access attributes). It
-- sets May_Be_Modified in the associated entity if there is one,
-- taking into account the rule that in the case of renamed objects,
-- it is the flag in the renamed object that must be set.
--
-- The parameter Sure is set True if the modification is sure to occur
-- (e.g. target of assignment, or out parameter), and to False if the
-- modification is only potential (e.g. address of entity taken).
function Object_Access_Level (Obj : Node_Id) return Uint;
-- Return the accessibility level of the view of the object Obj. For
-- convenience, qualified expressions applied to object names are also
-- allowed as actuals for this function.
function Original_Corresponding_Operation (S : Entity_Id) return Entity_Id;
-- [Ada 2012: AI05-0125-1]: If S is an inherited dispatching primitive S2,
-- or overrides an inherited dispatching primitive S2, the original
-- corresponding operation of S is the original corresponding operation of
-- S2. Otherwise, it is S itself.
function Original_Aspect_Pragma_Name (N : Node_Id) return Name_Id;
-- Retrieve the name of aspect or pragma N taking into account a possible
-- rewrite and whether the pragma is generated from an aspect as the names
-- may be different. The routine also deals with 'Class in which case it
-- returns the following values:
--
-- Invariant -> Name_uInvariant
-- Post'Class -> Name_uPost
-- Pre'Class -> Name_uPre
-- Type_Invariant -> Name_uType_Invariant
-- Type_Invariant'Class -> Name_uType_Invariant
function Policy_In_Effect (Policy : Name_Id) return Name_Id;
-- Given a policy, return the policy identifier associated with it. If no
-- such policy is in effect, the value returned is No_Name.
function Predicate_Tests_On_Arguments (Subp : Entity_Id) return Boolean;
-- Subp is the entity for a subprogram call. This function returns True if
-- predicate tests are required for the arguments in this call (this is the
-- normal case). It returns False for special cases where these predicate
-- tests should be skipped (see body for details).
function Primitive_Names_Match (E1, E2 : Entity_Id) return Boolean;
-- Returns True if the names of both entities correspond with matching
-- primitives. This routine includes support for the case in which one
-- or both entities correspond with entities built by Derive_Subprogram
-- with a special name to avoid being overridden (i.e. return true in case
-- of entities with names "nameP" and "name" or vice versa).
function Private_Component (Type_Id : Entity_Id) return Entity_Id;
-- Returns some private component (if any) of the given Type_Id.
-- Used to enforce the rules on visibility of operations on composite
-- types, that depend on the full view of the component type. For a
-- record type there may be several such components, we just return
-- the first one.
procedure Process_End_Label
(N : Node_Id;
Typ : Character;
Ent : Entity_Id);
-- N is a node whose End_Label is to be processed, generating all
-- appropriate cross-reference entries, and performing style checks
-- for any identifier references in the end label. Typ is either
-- 'e' or 't indicating the type of the cross-reference entity
-- (e for spec, t for body, see Lib.Xref spec for details). The
-- parameter Ent gives the entity to which the End_Label refers,
-- and to which cross-references are to be generated.
function Referenced (Id : Entity_Id; Expr : Node_Id) return Boolean;
-- Determine whether entity Id is referenced within expression Expr
function References_Generic_Formal_Type (N : Node_Id) return Boolean;
-- Returns True if the expression Expr contains any references to a
-- generic type. This can only happen within a generic template.
procedure Remove_Homonym (E : Entity_Id);
-- Removes E from the homonym chain
function Rep_To_Pos_Flag (E : Entity_Id; Loc : Source_Ptr) return Node_Id;
-- This is used to construct the second argument in a call to Rep_To_Pos
-- which is Standard_True if range checks are enabled (E is an entity to
-- which the Range_Checks_Suppressed test is applied), and Standard_False
-- if range checks are suppressed. Loc is the location for the node that
-- is returned (which is a New_Occurrence of the appropriate entity).
--
-- Note: one might think that it would be fine to always use True and
-- to ignore the suppress in this case, but it is generally better to
-- believe a request to suppress exceptions if possible, and further
-- more there is at least one case in the generated code (the code for
-- array assignment in a loop) that depends on this suppression.
procedure Require_Entity (N : Node_Id);
-- N is a node which should have an entity value if it is an entity name.
-- If not, then check if there were previous errors. If so, just fill
-- in with Any_Id and ignore. Otherwise signal a program error exception.
-- This is used as a defense mechanism against ill-formed trees caused by
-- previous errors (particularly in -gnatq mode).
function Requires_State_Refinement
(Spec_Id : Entity_Id;
Body_Id : Entity_Id) return Boolean;
-- Determine whether a package denoted by its spec and body entities
-- requires refinement of abstract states.
function Requires_Transient_Scope (Id : Entity_Id) return Boolean;
-- Id is a type entity. The result is True when temporaries of this type
-- need to be wrapped in a transient scope to be reclaimed properly when a
-- secondary stack is in use. Examples of types requiring such wrapping are
-- controlled types and variable-sized types including unconstrained
-- arrays.
procedure Reset_Analyzed_Flags (N : Node_Id);
-- Reset the Analyzed flags in all nodes of the tree whose root is N
procedure Restore_SPARK_Mode (Mode : SPARK_Mode_Type);
-- Set the current SPARK_Mode to whatever Mode denotes. This routime must
-- be used in tandem with Save_SPARK_Mode_And_Set.
function Returns_Unconstrained_Type (Subp : Entity_Id) return Boolean;
-- Return true if Subp is a function that returns an unconstrained type
function Root_Type_Of_Full_View (T : Entity_Id) return Entity_Id;
-- Similar to attribute Root_Type, but this version always follows the
-- Full_View of a private type (if available) while searching for the
-- ultimate derivation ancestor.
function Safe_To_Capture_Value
(N : Node_Id;
Ent : Entity_Id;
Cond : Boolean := False) return Boolean;
-- The caller is interested in capturing a value (either the current value,
-- or an indication that the value is non-null) for the given entity Ent.
-- This value can only be captured if sequential execution semantics can be
-- properly guaranteed so that a subsequent reference will indeed be sure
-- that this current value indication is correct. The node N is the
-- construct which resulted in the possible capture of the value (this
-- is used to check if we are in a conditional).
--
-- Cond is used to skip the test for being inside a conditional. It is used
-- in the case of capturing values from if/while tests, which already do a
-- proper job of handling scoping issues without this help.
--
-- The only entities whose values can be captured are OUT and IN OUT formal
-- parameters, and variables unless Cond is True, in which case we also
-- allow IN formals, loop parameters and constants, where we cannot ever
-- capture actual value information, but we can capture conditional tests.
function Same_Name (N1, N2 : Node_Id) return Boolean;
-- Determine if two (possibly expanded) names are the same name. This is
-- a purely syntactic test, and N1 and N2 need not be analyzed.
function Same_Object (Node1, Node2 : Node_Id) return Boolean;
-- Determine if Node1 and Node2 are known to designate the same object.
-- This is a semantic test and both nodes must be fully analyzed. A result
-- of True is decisively correct. A result of False does not necessarily
-- mean that different objects are designated, just that this could not
-- be reliably determined at compile time.
function Same_Type (T1, T2 : Entity_Id) return Boolean;
-- Determines if T1 and T2 represent exactly the same type. Two types
-- are the same if they are identical, or if one is an unconstrained
-- subtype of the other, or they are both common subtypes of the same
-- type with identical constraints. The result returned is conservative.
-- It is True if the types are known to be the same, but a result of
-- False is indecisive (e.g. the compiler may not be able to tell that
-- two constraints are identical).
function Same_Value (Node1, Node2 : Node_Id) return Boolean;
-- Determines if Node1 and Node2 are known to be the same value, which is
-- true if they are both compile time known values and have the same value,
-- or if they are the same object (in the sense of function Same_Object).
-- A result of False does not necessarily mean they have different values,
-- just that it is not possible to determine they have the same value.
procedure Save_SPARK_Mode_And_Set
(Context : Entity_Id;
Mode : out SPARK_Mode_Type);
-- Save the current SPARK_Mode in effect in Mode. Establish the SPARK_Mode
-- (if any) of a package or a subprogram denoted by Context. This routine
-- must be used in tandem with Restore_SPARK_Mode.
function Scalar_Part_Present (T : Entity_Id) return Boolean;
-- Tests if type T can be determined at compile time to have at least one
-- scalar part in the sense of the Valid_Scalars attribute. Returns True if
-- this is the case, and False if no scalar parts are present (meaning that
-- the result of Valid_Scalars applied to T is always vacuously True).
function Scope_Within_Or_Same (Scope1, Scope2 : Entity_Id) return Boolean;
-- Determines if the entity Scope1 is the same as Scope2, or if it is
-- inside it, where both entities represent scopes. Note that scopes
-- are only partially ordered, so Scope_Within_Or_Same (A,B) and
-- Scope_Within_Or_Same (B,A) can both be False for a given pair A,B.
function Scope_Within (Scope1, Scope2 : Entity_Id) return Boolean;
-- Like Scope_Within_Or_Same, except that this function returns
-- False in the case where Scope1 and Scope2 are the same scope.
procedure Set_Convention (E : Entity_Id; Val : Convention_Id);
-- Same as Basic_Set_Convention, but with an extra check for access types.
-- In particular, if E is an access-to-subprogram type, and Val is a
-- foreign convention, then we set Can_Use_Internal_Rep to False on E.
-- Also, if the Etype of E is set and is an anonymous access type with
-- no convention set, this anonymous type inherits the convention of E.
procedure Set_Current_Entity (E : Entity_Id);
pragma Inline (Set_Current_Entity);
-- Establish the entity E as the currently visible definition of its
-- associated name (i.e. the Node_Id associated with its name).
procedure Set_Debug_Info_Needed (T : Entity_Id);
-- Sets the Debug_Info_Needed flag on entity T , and also on any entities
-- that are needed by T (for an object, the type of the object is needed,
-- and for a type, various subsidiary types are needed -- see body for
-- details). Never has any effect on T if the Debug_Info_Off flag is set.
-- This routine should always be used instead of Set_Needs_Debug_Info to
-- ensure that subsidiary entities are properly handled.
procedure Set_Entity_With_Checks (N : Node_Id; Val : Entity_Id);
-- This procedure has the same calling sequence as Set_Entity, but it
-- performs additional checks as follows:
--
-- If Style_Check is set, then it calls a style checking routine which
-- can check identifier spelling style. This procedure also takes care
-- of checking the restriction No_Implementation_Identifiers.
--
-- If restriction No_Abort_Statements is set, then it checks that the
-- entity is not Ada.Task_Identification.Abort_Task.
--
-- If restriction No_Dynamic_Attachment is set, then it checks that the
-- entity is not one of the restricted names for this restriction.
--
-- If restriction No_Long_Long_Integers is set, then it checks that the
-- entity is not Standard.Long_Long_Integer.
--
-- If restriction No_Implementation_Identifiers is set, then it checks
-- that the entity is not implementation defined.
procedure Set_Name_Entity_Id (Id : Name_Id; Val : Entity_Id);
pragma Inline (Set_Name_Entity_Id);
-- Sets the Entity_Id value associated with the given name, which is the
-- Id of the innermost visible entity with the given name. See the body
-- of package Sem_Ch8 for further details on the handling of visibility.
procedure Set_Next_Actual (Ass1_Id : Node_Id; Ass2_Id : Node_Id);
-- The arguments may be parameter associations, whose descendants
-- are the optional formal name and the actual parameter. Positional
-- parameters are already members of a list, and do not need to be
-- chained separately. See also First_Actual and Next_Actual.
procedure Set_Optimize_Alignment_Flags (E : Entity_Id);
pragma Inline (Set_Optimize_Alignment_Flags);
-- Sets Optimize_Alignment_Space/Time flags in E from current settings
procedure Set_Public_Status (Id : Entity_Id);
-- If an entity (visible or otherwise) is defined in a library
-- package, or a package that is itself public, then this subprogram
-- labels the entity public as well.
procedure Set_Referenced_Modified (N : Node_Id; Out_Param : Boolean);
-- N is the node for either a left hand side (Out_Param set to False),
-- or an Out or In_Out parameter (Out_Param set to True). If there is
-- an assignable entity being referenced, then the appropriate flag
-- (Referenced_As_LHS if Out_Param is False, Referenced_As_Out_Parameter
-- if Out_Param is True) is set True, and the other flag set False.
procedure Set_Scope_Is_Transient (V : Boolean := True);
-- Set the flag Is_Transient of the current scope
procedure Set_Size_Info (T1, T2 : Entity_Id);
pragma Inline (Set_Size_Info);
-- Copies the Esize field and Has_Biased_Representation flag from sub(type)
-- entity T2 to (sub)type entity T1. Also copies the Is_Unsigned_Type flag
-- in the fixed-point and discrete cases, and also copies the alignment
-- value from T2 to T1. It does NOT copy the RM_Size field, which must be
-- separately set if this is required to be copied also.
function Scope_Is_Transient return Boolean;
-- True if the current scope is transient
function Static_Boolean (N : Node_Id) return Uint;
-- This function analyzes the given expression node and then resolves it
-- as Standard.Boolean. If the result is static, then Uint_1 or Uint_0 is
-- returned corresponding to the value, otherwise an error message is
-- output and No_Uint is returned.
function Static_Integer (N : Node_Id) return Uint;
-- This function analyzes the given expression node and then resolves it
-- as any integer type. If the result is static, then the value of the
-- universal expression is returned, otherwise an error message is output
-- and a value of No_Uint is returned.
function Statically_Different (E1, E2 : Node_Id) return Boolean;
-- Return True if it can be statically determined that the Expressions
-- E1 and E2 refer to different objects
function Subject_To_Loop_Entry_Attributes (N : Node_Id) return Boolean;
-- Determine whether node N is a loop statement subject to at least one
-- 'Loop_Entry attribute.
function Subprogram_Access_Level (Subp : Entity_Id) return Uint;
-- Return the accessibility level of the view denoted by Subp
function Support_Atomic_Primitives (Typ : Entity_Id) return Boolean;
-- Return True if Typ supports the GCC built-in atomic operations (i.e. if
-- Typ is properly sized and aligned).
procedure Trace_Scope (N : Node_Id; E : Entity_Id; Msg : String);
-- Print debugging information on entry to each unit being analyzed
procedure Transfer_Entities (From : Entity_Id; To : Entity_Id);
-- Move a list of entities from one scope to another, and recompute
-- Is_Public based upon the new scope.
function Type_Access_Level (Typ : Entity_Id) return Uint;
-- Return the accessibility level of Typ
function Type_Without_Stream_Operation
(T : Entity_Id;
Op : TSS_Name_Type := TSS_Null) return Entity_Id;
-- AI05-0161: In Ada 2012, if the restriction No_Default_Stream_Attributes
-- is active then we cannot generate stream subprograms for composite types
-- with elementary subcomponents that lack user-defined stream subprograms.
-- This predicate determines whether a type has such an elementary
-- subcomponent. If Op is TSS_Null, a type that lacks either Read or Write
-- prevents the construction of a composite stream operation. If Op is
-- specified we check only for the given stream operation.
function Unique_Defining_Entity (N : Node_Id) return Entity_Id;
-- Return the entity which represents declaration N, so that different
-- views of the same entity have the same unique defining entity:
-- * package spec and body;
-- * subprogram declaration, subprogram stub and subprogram body;
-- * private view and full view of a type;
-- * private view and full view of a deferred constant.
-- In other cases, return the defining entity for N.
function Unique_Entity (E : Entity_Id) return Entity_Id;
-- Return the unique entity for entity E, which would be returned by
-- Unique_Defining_Entity if applied to the enclosing declaration of E.
function Unique_Name (E : Entity_Id) return String;
-- Return a unique name for entity E, which could be used to identify E
-- across compilation units.
function Unit_Is_Visible (U : Entity_Id) return Boolean;
-- Determine whether a compilation unit is visible in the current context,
-- because there is a with_clause that makes the unit available. Used to
-- provide better messages on common visiblity errors on operators.
function Universal_Interpretation (Opnd : Node_Id) return Entity_Id;
-- Yields Universal_Integer or Universal_Real if this is a candidate
function Unqualify (Expr : Node_Id) return Node_Id;
pragma Inline (Unqualify);
-- Removes any qualifications from Expr. For example, for T1'(T2'(X)), this
-- returns X. If Expr is not a qualified expression, returns Expr.
function Visible_Ancestors (Typ : Entity_Id) return Elist_Id;
-- [Ada 2012:AI-0125-1]: Collect all the visible parents and progenitors
-- of a type extension or private extension declaration. If the full-view
-- of private parents and progenitors is available then it is used to
-- generate the list of visible ancestors; otherwise their partial
-- view is added to the resulting list.
function Within_Init_Proc return Boolean;
-- Determines if Current_Scope is within an init proc
function Within_Scope (E : Entity_Id; S : Entity_Id) return Boolean;
-- Returns True if entity Id is declared within scope S
procedure Wrong_Type (Expr : Node_Id; Expected_Type : Entity_Id);
-- Output error message for incorrectly typed expression. Expr is the node
-- for the incorrectly typed construct (Etype (Expr) is the type found),
-- and Expected_Type is the entity for the expected type. Note that Expr
-- does not have to be a subexpression, anything with an Etype field may
-- be used.
end Sem_Util;