------------------------------------------------------------------------------
-- This package defines the structure of the abstract syntax tree. The Tree
--- package provides a basic tree structure. Sinfo describes how this
--- structure is used to represent the syntax of an Ada program.
+-- package provides a basic tree structure. Sinfo describes how this structure
+-- is used to represent the syntax of an Ada program.
-- Note: the grammar used here is taken from Version 5.95 of the RM, dated
-- November 1994. The grammar in the RM is followed very closely in the tree
-- program, but also the results of semantic analysis. In particular, the
-- nodes for defining identifiers, defining character literals and defining
-- operator symbols, collectively referred to as entities, represent what
--- would normally be regarded as the symbol table information. In addition
--- a number of the tree nodes contain semantic information.
+-- would normally be regarded as the symbol table information. In addition a
+-- number of the tree nodes contain semantic information.
--- WARNING: There is a C version of this package. Any changes to this
--- source file must be properly reflected in this C header file sinfo.h
--- which is created automatically from sinfo.ads using xsinfo.adb.
+-- WARNING: There is a C version of this package. Any changes to this source
+-- file must be properly reflected in this C header file sinfo.h which is
+-- created automatically from sinfo.ads using xsinfo.adb.
with Types; use Types;
with Uintp; use Uintp;
---------------------------------
-- If changes are made to this file, a number of related steps must be
- -- carried out to ensure consistency. First, if a field access function
- -- is added, it appears in seven places:
+ -- carried out to ensure consistency. First, if a field access function is
+ -- added, it appears in seven places:
-- The documentation associated with the node
-- The spec of the access function in sinfo.ads
-- The body of the set procedure in sinfo.adb
-- The pragma Inline at the end of sinfo.ads for the set procedure
- -- The field chosen must be consistent in all places, and, for a node
- -- that is a subexpression, must not overlap any of the standard
- -- expression fields.
+ -- The field chosen must be consistent in all places, and, for a node that
+ -- is a subexpression, must not overlap any of the standard expression
+ -- fields.
-- In addition, if any of the standard expression fields is changed, then
-- the utiliy program which creates the Treeprs spec (in file treeprs.ads)
-- Finally, four utility programs must be run:
- -- Run CSinfo to check that you have made the changes consistently.
- -- It checks most of the rules given above, with clear error messages.
- -- This utility reads sinfo.ads and sinfo.adb and generates a report
- -- to standard output.
+ -- Run CSinfo to check that you have made the changes consistently. It
+ -- checks most of the rules given above, with clear error messages. This
+ -- utility reads sinfo.ads and sinfo.adb and generates a report to
+ -- standard output.
-- Run XSinfo to create a-sinfo.h, the corresponding C header. This
- -- utility reads sinfo.ads and generates a-sinfo.h. Note that it
- -- does not need to read sinfo.adb, since the contents of the body
- -- are algorithmically determinable from the spec.
+ -- utility reads sinfo.ads and generates a-sinfo.h. Note that it does
+ -- not need to read sinfo.adb, since the contents of the body are
+ -- algorithmically determinable from the spec.
- -- Run XTreeprs to create treeprs.ads, an updated version of
- -- the module that is used to drive the tree print routine. This
- -- utility reads (but does not modify) treeprs.adt, the template
- -- that provides the basic structure of the file, and then fills
- -- in the data from the comments in sinfo.ads.
+ -- Run XTreeprs to create treeprs.ads, an updated version of the module
+ -- that is used to drive the tree print routine. This utility reads (but
+ -- does not modify) treeprs.adt, the template that provides the basic
+ -- structure of the file, and then fills in the data from the comments
+ -- in sinfo.ads.
- -- Run XNmake to create nmake.ads and nmake.adb, the package body
- -- and spec of the Nmake package which contains functions for
- -- constructing nodes.
+ -- Run XNmake to create nmake.ads and nmake.adb, the package body and
+ -- spec of the Nmake package which contains functions for constructing
+ -- nodes.
- -- Note: sometime we could write a utility that actually generated the
- -- body of sinfo from the spec instead of simply checking it, since, as
- -- noted above, the contents of the body can be determined from the spec.
+ -- Note: sometime we could write a utility that actually generated the body
+ -- of sinfo from the spec instead of simply checking it, since, as noted
+ -- above, the contents of the body can be determined from the spec.
--------------------------------
-- Implicit Nodes in the Tree --
--------------------------------
- -- Generally the structure of the tree very closely follows the grammar
- -- as defined in the RM. However, certain nodes are omitted to save
- -- space and simplify semantic processing. Two general classes of such
- -- omitted nodes are as follows:
+ -- Generally the structure of the tree very closely follows the grammar as
+ -- defined in the RM. However, certain nodes are omitted to save space and
+ -- simplify semantic processing. Two general classes of such omitted nodes
+ -- are as follows:
-- If the only possibilities for a non-terminal are one or more other
- -- non terminals (i.e. the rule is a "skinny" rule), then usually the
+ -- non-terminals (i.e. the rule is a "skinny" rule), then usually the
-- corresponding node is omitted from the tree, and the target construct
- -- appears directly. For example, a real type definition is either a
- -- floating point definition or a fixed point definition. No explicit
- -- node appears for real type definition. Instead either the floating
- -- point definition or fixed point definition appears directly.
+ -- appears directly. For example, a real type definition is either
+ -- floating point definition or a fixed point definition. No explicit node
+ -- appears for real type definition. Instead either the floating point
+ -- definition or fixed point definition appears directly.
-- If a non-terminal corresponds to a list of some other non-terminal
- -- (possibly with separating punctuation), then usually it is omitted
- -- from the tree, and a list of components appears instead. For
- -- example, sequence of statements does not appear explicitly in the
- -- tree. Instead a list of statements appears directly.
+ -- (possibly with separating punctuation), then usually it is omitted from
+ -- the tree, and a list of components appears instead. For example,
+ -- sequence of statements does not appear explicitly in the tree. Instead
+ -- a list of statements appears directly.
-- Some additional cases of omitted nodes occur and are documented
-- individually. In particular, many nodes are omitted in the tree
-------------------------------------------
-- In several declarative forms in the syntax, lists of defining
- -- identifiers appear (object declarations, component declarations,
- -- number declarations etc.)
+ -- identifiers appear (object declarations, component declarations, number
+ -- declarations etc.)
- -- The semantics of such statements are equivalent to a series of
- -- identical declarations of single defining identifiers (except that
- -- conformance checks require the same grouping of identifiers in the
- -- parameter case).
+ -- The semantics of such statements are equivalent to a series of identical
+ -- declarations of single defining identifiers (except that conformance
+ -- checks require the same grouping of identifiers in the parameter case).
-- To simplify semantic processing, the parser breaks down such multiple
-- declaration cases into sequences of single declarations, duplicating
- -- type and initialization information as required. The flags More_Ids
- -- and Prev_Ids are used to record the original form of the source in
- -- the case where the original source used a list of names, More_Ids
- -- being set on all but the last name and Prev_Ids being set on all
- -- but the first name. These flags are used to reconstruct the original
- -- source (e.g. in the Sprint package), and also are included in the
- -- conformance checks, but otherwise have no semantic significance.
+ -- type and initialization information as required. The flags More_Ids and
+ -- Prev_Ids are used to record the original form of the source in the case
+ -- where the original source used a list of names, More_Ids being set on
+ -- all but the last name and Prev_Ids being set on all but the first name.
+ -- These flags are used to reconstruct the original source (e.g. in the
+ -- Sprint package), and also are included in the conformance checks, but
+ -- otherwise have no semantic significance.
-- Note: the reason that we use More_Ids and Prev_Ids rather than
-- First_Name and Last_Name flags is so that the flags are off in the
-----------------------
-- With a few exceptions, if a construction of the form {non-terminal}
- -- appears in the tree, lists are used in the corresponding tree node
- -- (see package Nlists for handling of node lists). In this case a field
- -- of the parent node points to a list of nodes for the non-terminal. The
- -- field name for such fields has a plural name which always ends in "s".
- -- For example, a case statement has a field Alternatives pointing to a
- -- list of case statement alternative nodes.
+ -- appears in the tree, lists are used in the corresponding tree node (see
+ -- package Nlists for handling of node lists). In this case a field of the
+ -- parent node points to a list of nodes for the non-terminal. The field
+ -- name for such fields has a plural name which always ends in "s". For
+ -- example, a case statement has a field Alternatives pointing to list of
+ -- case statement alternative nodes.
- -- Only fields pointing to lists have names ending in "s", so generally
- -- the structure is strongly typed, fields not ending in s point to
- -- single nodes, and fields ending in s point to lists.
+ -- Only fields pointing to lists have names ending in "s", so generally the
+ -- structure is strongly typed, fields not ending in s point to single
+ -- nodes, and fields ending in s point to lists.
-- The following example shows how a traversal of a list is written. We
- -- suppose here that Stmt points to a N_Case_Statement node which has
- -- a list field called Alternatives:
+ -- suppose here that Stmt points to a N_Case_Statement node which has a
+ -- list field called Alternatives:
-- Alt := First (Alternatives (Stmt));
-- while Present (Alt) loop
-- Alt := Next (Alt);
-- end loop;
- -- The Present function tests for Empty, which in this case signals the
- -- end of the list. First returns Empty immediately if the list is empty.
+ -- The Present function tests for Empty, which in this case signals the end
+ -- of the list. First returns Empty immediately if the list is empty.
-- Present is defined in Atree, First and Next are defined in Nlists.
-- The exceptions to this rule occur with {DEFINING_IDENTIFIERS} in all
-- Pragmas --
-------------
- -- Pragmas can appear in many different context, but are not included
- -- in the grammar. Still they must appear in the tree, so they can be
- -- properly processed.
+ -- Pragmas can appear in many different context, but are not included in
+ -- the grammar. Still they must appear in the tree, so they can be properly
+ -- processed.
- -- Two approaches are used. In some cases, an extra field is defined
- -- in an appropriate node that contains a list of pragmas appearing
- -- in the expected context. For example pragmas can appear before an
+ -- Two approaches are used. In some cases, an extra field is defined in an
+ -- appropriate node that contains a list of pragmas appearing in the
+ -- expected context. For example pragmas can appear before an
-- Accept_Alternative in a Selective_Accept_Statement, and these pragmas
-- appear in the Pragmas_Before field of the N_Accept_Alternative node.
-- The other approach is to simply allow pragmas to appear in syntactic
-- lists where the grammar (of course) does not include the possibility.
- -- For example, the Variants field of an N_Variant_Part node points to
- -- a list that can contain both N_Pragma and N_Variant nodes.
+ -- For example, the Variants field of an N_Variant_Part node points to a
+ -- list that can contain both N_Pragma and N_Variant nodes.
-- To make processing easier in the latter case, the Nlists package
-- provides a set of routines (First_Non_Pragma, Last_Non_Pragma,
- -- Next_Non_Pragma, Prev_Non_Pragma) that allow such lists to be
- -- handled ignoring all pragmas.
+ -- Next_Non_Pragma, Prev_Non_Pragma) that allow such lists to be handled
+ -- ignoring all pragmas.
-- In the case of the variants list, we can either write:
-- Variant := Next_Non_Pragma (Variant);
-- end loop;
- -- In the first form of the loop, Variant can either be an N_Pragma or
- -- an N_Variant node. In the second form, Variant can only be N_Variant
- -- since all pragmas are skipped.
+ -- In the first form of the loop, Variant can either be an N_Pragma or an
+ -- N_Variant node. In the second form, Variant can only be N_Variant since
+ -- all pragmas are skipped.
---------------------
-- Optional Fields --
---------------------
-- Fields which correspond to a section of the syntax enclosed in square
- -- brackets are generally omitted (and the corresponding field set to
- -- Empty for a node, or No_List for a list). The documentation of such
- -- fields notes these cases. One exception to this rule occurs in the
- -- case of possibly empty statement sequences (such as the sequence of
- -- statements in an entry call alternative). Such cases appear in the
- -- syntax rules as [SEQUENCE_OF_STATEMENTS] and the fields corresponding
- -- to such optional statement sequences always contain an empty list (not
- -- No_List) if no statements are present.
-
- -- Note: the utility program that constructs the body and spec of the
- -- Nmake package relies on the format of the comments to determine if
- -- a field should have a default value in the corresponding make routine.
- -- The rule is that if the first line of the description of the field
- -- contains the string "(set to xxx if", then a default value of xxx is
- -- provided for this field in the corresponding Make_yyy routine.
+ -- brackets are generally omitted (and the corresponding field set to Empty
+ -- for a node, or No_List for a list). The documentation of such fields
+ -- notes these cases. One exception to this rule occurs in the case of
+ -- possibly empty statement sequences (such as the sequence of statements
+ -- in an entry call alternative). Such cases appear in the syntax rules as
+ -- [SEQUENCE_OF_STATEMENTS] and the fields corresponding to such optional
+ -- statement sequences always contain an empty list (not No_List) if no
+ -- statements are present.
+
+ -- Note: the utility program that constructs the body and spec of the Nmake
+ -- package relies on the format of the comments to determine if a field
+ -- should have a default value in the corresponding make routine. The rule
+ -- is that if the first line of the description of the field contains the
+ -- string "(set to xxx if", then a default value of xxx is provided for
+ -- this field in the corresponding Make_yyy routine.
-----------------------------------
-- Note on Body/Spec Terminology --
-- In informal discussions about Ada, it is customary to refer to package
-- and subprogram specs and bodies. However, this is not technically
-- correct, what is normally referred to as a spec or specification is in
- -- fact a package declaration or subprogram declaration. We are careful
- -- in GNAT to use the correct terminology and in particular, the full
- -- word specification is never used as an incorrect substitute for
- -- declaration. The structure and terminology used in the tree also
- -- reflects the grammar and thus uses declaration and specification in
- -- the technically correct manner.
-
- -- However, there are contexts in which the informal terminology is
- -- useful. We have the word "body" to refer to the Interp_Etype declared by
- -- the declaration of a unit body, and in some contexts we need a
- -- similar term to refer to the entity declared by the package or
- -- subprogram declaration, and simply using declaration can be confusing
- -- since the body also has a declaration.
-
- -- An example of such a context is the link between the package body
- -- and its declaration. With_Declaration is confusing, since
- -- the package body itself is a declaration.
-
- -- To deal with this problem, we reserve the informal term Spec, i.e.
- -- the popular abbreviation used in this context, to refer to the entity
+ -- fact a package declaration or subprogram declaration. We are careful in
+ -- GNAT to use the correct terminology and in particular, the full word
+ -- specification is never used as an incorrect substitute for declaration.
+ -- The structure and terminology used in the tree also reflects the grammar
+ -- and thus uses declaration and specification in the technically correct
+ -- manner.
+
+ -- However, there are contexts in which the informal terminology is useful.
+ -- We have the word "body" to refer to the Interp_Etype declared by the
+ -- declaration of a unit body, and in some contexts we need similar term to
+ -- refer to the entity declared by the package or subprogram declaration,
+ -- and simply using declaration can be confusing since the body also has a
+ -- declaration.
+
+ -- An example of such a context is the link between the package body and
+ -- its declaration. With_Declaration is confusing, since the package body
+ -- itself is a declaration.
+
+ -- To deal with this problem, we reserve the informal term Spec, i.e. the
+ -- popular abbreviation used in this context, to refer to the entity
-- declared by the package or subprogram declaration. So in the above
-- example case, the field in the body is called With_Spec.
-- Another important context for the use of the word Spec is in error
- -- messages, where a hyper-correct use of declaration would be confusing
- -- to a typical Ada programmer, and even for an expert programmer can
- -- cause confusion since the body has a declaration as well.
+ -- messages, where a hyper-correct use of declaration would be confusing to
+ -- a typical Ada programmer, and even for an expert programmer can cause
+ -- confusion since the body has a declaration as well.
-- So, to summarize:
-- Internal Use Nodes --
------------------------
- -- These are Node_Kind settings used in the internal implementation
- -- which are not logically part of the specification.
+ -- These are Node_Kind settings used in the internal implementation which
+ -- are not logically part of the specification.
-- N_Unused_At_Start
-- Completely unused entry at the start of the enumeration type. This
-- Completely unused entry at the end of the enumeration type. This is
-- handy so that arrays with Node_Kind as the index type have an extra
-- entry at the end (see for example the use of the Pchar_Pos_Array in
- -- Treepr, where the extra entry provides the limit value when dealing
- -- with the last used entry in the array).
+ -- Treepr, where the extra entry provides the limit value when dealing with
+ -- the last used entry in the array).
-----------------------------------------
-- Note on the settings of Sloc fields --
-----------------------------------------
- -- The Sloc field of nodes that come from the source is set by the
- -- parser. For internal nodes, and nodes generated during expansion
- -- the Sloc is usually set in the call to the constructor for the node.
- -- In general the Sloc value chosen for an internal node is the Sloc of
- -- the source node whose processing is responsible for the expansion. For
- -- example, the Sloc of an inherited primitive operation is the Sloc of
- -- the corresponding derived type declaration.
+ -- The Sloc field of nodes that come from the source is set by the parser.
+ -- For internal nodes, and nodes generated during expansion the Sloc is
+ -- usually set in the call to the constructor for the node. In general the
+ -- Sloc value chosen for an internal node is the Sloc of the source node
+ -- whose processing is responsible for the expansion. For example, the Sloc
+ -- of an inherited primitive operation is the Sloc of the corresponding
+ -- derived type declaration.
- -- For the nodes of a generic instantiation, the Sloc value is encoded
- -- to represent both the original Sloc in the generic unit, and the Sloc
- -- of the instantiation itself. See Sinput.ads for details.
+ -- For the nodes of a generic instantiation, the Sloc value is encoded to
+ -- represent both the original Sloc in the generic unit, and the Sloc of
+ -- the instantiation itself. See Sinput.ads for details.
-- Subprogram instances create two callable entities: one is the visible
-- subprogram instance, and the other is an anonymous subprogram nested
-- In the following node definitions, all fields, both syntactic and
-- semantic, are documented. The one exception is in the case of entities
- -- (defining indentifiers, character literals and operator symbols),
- -- where the usage of the fields depends on the entity kind. Entity
- -- fields are fully documented in the separate package Einfo.
+ -- (defining indentifiers, character literals and operator symbols), where
+ -- the usage of the fields depends on the entity kind. Entity fields are
+ -- fully documented in the separate package Einfo.
- -- In the node definitions, three common sets of fields are abbreviated
- -- to save both space in the documentation, and also space in the string
+ -- In the node definitions, three common sets of fields are abbreviated to
+ -- save both space in the documentation, and also space in the string
-- (defined in Tree_Print_Strings) used to print trees. The following
-- abbreviations are used:
-- Note: see under (EXPRESSION) for further details on the use of
-- the Paren_Count field to record the number of parentheses levels.
- -- Node_Kind is the type used in the Nkind field to indicate the node
- -- kind. The actual definition of this type is given later (the reason
- -- for this is that we want the descriptions ordered by logical chapter
- -- in the RM, but the type definition is reordered to facilitate the
- -- definition of some subtype ranges. The individual descriptions of
- -- the nodes show how the various fields are used in each node kind,
- -- as well as providing logical names for the fields. Functions and
- -- procedures are provided for accessing and setting these fields
- -- using these logical names.
+ -- Node_Kind is the type used in the Nkind field to indicate the node kind.
+ -- The actual definition of this type is given later (the reason for this
+ -- is that we want the descriptions ordered by logical chapter in the RM,
+ -- but the type definition is reordered to facilitate the definition of
+ -- some subtype ranges. The individual descriptions of the nodes show how
+ -- the various fields are used in each node kind, as well as providing
+ -- logical names for the fields. Functions and procedures are provided for
+ -- accessing and setting these fields using these logical names.
-----------------------
-- Gigi Restrictions --
-- The following flag fields appear in all nodes
-- Analyzed (Flag1)
- -- This flag is used to indicate that a node (and all its children
- -- have been analyzed. It is used to avoid reanalysis of a node that
- -- has already been analyzed, both for efficiency and functional
- -- correctness reasons.
+ -- This flag is used to indicate that a node (and all its children have
+ -- been analyzed. It is used to avoid reanalysis of a node that has
+ -- already been analyzed, both for efficiency and functional correctness
+ -- reasons.
-- Comes_From_Source (Flag2)
- -- This flag is on for any nodes built by the scanner or parser from
- -- the source program, and off for any nodes built by the analyzer or
+ -- This flag is on for any nodes built by the scanner or parser from the
+ -- source program, and off for any nodes built by the analyzer or
-- expander. It indicates that a node comes from the original source.
-- This flag is defined in Atree.
-- Error_Posted (Flag3)
- -- This flag is used to avoid multiple error messages being posted
- -- on or referring to the same node. This flag is set if an error
- -- message refers to a node or is posted on its source location,
- -- and has the effect of inhibiting further messages involving
- -- this same node.
+ -- This flag is used to avoid multiple error messages being posted on or
+ -- referring to the same node. This flag is set if an error message
+ -- refers to a node or is posted on its source location, and has the
+ -- effect of inhibiting further messages involving this same node.
-- Has_Dynamic_Length_Check (Flag10-Sem)
- -- This flag is present on all nodes. It is set to indicate that one
- -- of the routines in unit Checks has generated a length check action
- -- which has been inserted at the flagged node. This is used to avoid
- -- the generation of duplicate checks.
+ -- This flag is present on all nodes. It is set to indicate that one of
+ -- the routines in unit Checks has generated a length check action which
+ -- has been inserted at the flagged node. This is used to avoid the
+ -- generation of duplicate checks.
-- Has_Dynamic_Range_Check (Flag12-Sem)
- -- This flag is present on all nodes. It is set to indicate that one
- -- of the routines in unit Checks has generated a range check action
- -- which has been inserted at the flagged node. This is used to avoid
- -- the generation of duplicate checks.
+ -- This flag is present on all nodes. It is set to indicate that one of
+ -- the routines in unit Checks has generated a range check action which
+ -- has been inserted at the flagged node. This is used to avoid the
+ -- generation of duplicate checks.
------------------------------------
-- Description of Semantic Fields --
------------------------------------
- -- The meaning of the syntactic fields is generally clear from their
- -- names without any further description, since the names are chosen
- -- to correspond very closely to the syntax in the reference manual.
- -- This section describes the usage of the semantic fields, which are
- -- used to contain additional information determined during semantic
- -- analysis.
+ -- The meaning of the syntactic fields is generally clear from their names
+ -- without any further description, since the names are chosen to
+ -- correspond very closely to the syntax in the reference manual. This
+ -- section describes the usage of the semantic fields, which are used to
+ -- contain additional information determined during semantic analysis.
-- ABE_Is_Certain (Flag18-Sem)
- -- This flag is set in an instantiation node or a call node is
- -- determined to be sure to raise an ABE. This is used to trigger
- -- special handling of such cases, particularly in the instantiation
- -- case where we avoid instantiating the body if this flag is set.
- -- This flag is also present in an N_Formal_Package_Declaration_Node
- -- since formal package declarations are treated like instantiations,
- -- but it is always set to False in this context.
+ -- This flag is set in an instantiation node or a call node is determined
+ -- to be sure to raise an ABE. This is used to trigger special handling
+ -- of such cases, particularly in the instantiation case where we avoid
+ -- instantiating the body if this flag is set. This flag is also present
+ -- in an N_Formal_Package_Declaration_Node since formal package
+ -- declarations are treated like instantiations, but it is always set to
+ -- False in this context.
-- Accept_Handler_Records (List5-Sem)
- -- This field is present only in an N_Accept_Alternative node. It is
- -- used to temporarily hold the exception handler records from an
- -- accept statement in a selective accept. These exception handlers
- -- will eventually be placed in the Handler_Records list of the
- -- procedure built for this accept (see Expand_N_Selective_Accept
- -- procedure in Exp_Ch9 for further details).
+ -- This field is present only in an N_Accept_Alternative node. It is used
+ -- to temporarily hold the exception handler records from an accept
+ -- statement in a selective accept. These exception handlers will
+ -- eventually be placed in the Handler_Records list of the procedure
+ -- built for this accept (see Expand_N_Selective_Accept procedure in
+ -- Exp_Ch9 for further details).
-- Access_Types_To_Process (Elist2-Sem)
-- Present in N_Freeze_Entity nodes for Incomplete or private types.
- -- Contains the list of access types which may require specific
- -- treatment when the nature of the type completion is completely
- -- known. An example of such treatement is the generation of the
- -- associated_final_chain.
+ -- Contains the list of access types which may require specific treatment
+ -- when the nature of the type completion is completely known. An example
+ -- of such treatement is the generation of the associated_final_chain.
-- Actions (List1-Sem)
- -- This field contains a sequence of actions that are associated
- -- with the node holding the field. See the individual node types
- -- for details of how this field is used, as well as the description
- -- of the specific use for a particular node type.
+ -- This field contains a sequence of actions that are associated with the
+ -- node holding the field. See the individual node types for details of
+ -- how this field is used, as well as the description of the specific use
+ -- for a particular node type.
-- Activation_Chain_Entity (Node3-Sem)
-- This is used in tree nodes representing task activators (blocks,
-- subprogram bodies, package declarations, and task bodies). It is
-- initially Empty, and then gets set to point to the entity for the
-- declared Activation_Chain variable when the first task is declared.
- -- When tasks are declared in the corresponding declarative region
- -- this entity is located by name (its name is always _Chain) and
- -- the declared tasks are added to the chain.
+ -- When tasks are declared in the corresponding declarative region this
+ -- entity is located by name (its name is always _Chain) and the declared
+ -- tasks are added to the chain.
-- Acts_As_Spec (Flag4-Sem)
- -- A flag set in the N_Subprogram_Body node for a subprogram body
- -- which is acting as its own spec. This flag also appears in the
- -- compilation unit node at the library level for such a subprogram
- -- (see further description in spec of Lib package).
+ -- A flag set in the N_Subprogram_Body node for a subprogram body which
+ -- is acting as its own spec. This flag also appears in the compilation
+ -- unit node at the library level for such a subprogram (see further
+ -- description in spec of Lib package).
-- Actual_Designated_Subtype (Node2-Sem)
- -- Present in N_Free_Statement and N_Explicit_Dereference nodes. If
- -- GIGI needs to known the dynamic constrained subtype of the designated
+ -- Present in N_Free_Statement and N_Explicit_Dereference nodes. If gigi
+ -- needs to known the dynamic constrained subtype of the designated
-- object, this attribute is set to that type. This is done for
-- N_Free_Statements for access-to-classwide types and access to
- -- unconstrained packed array types, and for N_Explicit_Dereference
- -- when the designated type is an unconstrained packed array and the
+ -- unconstrained packed array types, and for N_Explicit_Dereference when
+ -- the designated type is an unconstrained packed array and the
-- dereference is the prefix of a 'Size attribute reference.
-- Aggregate_Bounds (Node3-Sem)
-- Present in array N_Aggregate nodes. If the aggregate contains
-- component associations this field points to an N_Range node whose
-- bounds give the lowest and highest discrete choice values. If the
- -- named aggregate contains a dynamic or null choice this field is
- -- empty. If the aggregate contains positional elements this field
- -- points to an N_Integer_Literal node giving the number of positional
- -- elements. Note that if the aggregate contains positional elements
- -- and an other choice the N_Integer_Literal only accounts for the
- -- number of positional elements.
+ -- named aggregate contains a dynamic or null choice this field is empty.
+ -- If the aggregate contains positional elements this field points to an
+ -- N_Integer_Literal node giving the number of positional elements. Note
+ -- that if the aggregate contains positional elements and an other choice
+ -- the N_Integer_Literal only accounts for the number of positional
+ -- elements.
-- All_Others (Flag11-Sem)
- -- Present in an N_Others_Choice node. This flag is set in the case
- -- of an others exception where all exceptions are to be caught, even
- -- those that are not normally handled (in particular the tasking abort
- -- signal). This is used for translation of the at end handler into
- -- a normal exception handler.
+ -- Present in an N_Others_Choice node. This flag is set in the case of an
+ -- others exception where all exceptions are to be caught, even those
+ -- that are not normally handled (in particular the tasking abort
+ -- signal). This is used for translation of the at end handler into a
+ -- normal exception handler.
-- Assignment_OK (Flag15-Sem)
-- This flag is set in a subexpression node for an object, indicating
-- limited type objects (such as tasks), setting discriminant fields,
-- setting tag values, etc. N_Object_Declaration nodes also have this
-- flag defined. Here it is used to indicate that an initialization
- -- expression is valid, even where it would normally not be allowed
- -- (e.g. where the type involved is limited).
+ -- expression is valid, even where it would normally not be allowed (e.g.
+ -- where the type involved is limited).
-- Associated_Node (Node4-Sem)
-- Present in nodes that can denote an entity: identifiers, character
-- literals, operator symbols, expanded names, operator nodes, and
- -- attribute reference nodes (all these nodes have an Entity field).
- -- This field is also present in N_Aggregate, N_Selected_Component,
- -- and N_Extension_Aggregate nodes. This field is used in generic
- -- processing to create links between the generic template and the
- -- generic copy. See Sem_Ch12.Get_Associated_Node for full details.
- -- Note that this field overlaps Entity, which is fine, since, as
- -- explained in Sem_Ch12, the normal function of Entity is not
- -- required at the point where the Associated_Node is set. Note
- -- also, that in generic templates, this means that the Entity field
- -- does not necessarily point to an Entity. Since the back end is
- -- expected to ignore generic templates, this is harmless.
+ -- attribute reference nodes (all these nodes have an Entity field). This
+ -- field is also present in N_Aggregate, N_Selected_Component, and
+ -- N_Extension_Aggregate nodes. This field is used in generic processing
+ -- to create links between the generic template and the generic copy. See
+ -- Sem_Ch12.Get_Associated_Node for full details. Note that this field
+ -- overlaps Entity, which is fine, since, as explained in Sem_Ch12, the
+ -- normal function of Entity is not required at the point where the
+ -- Associated_Node is set. Note also, that in generic templates, this
+ -- means that the Entity field does not necessarily point to an Entity.
+ -- Since the back end is expected to ignore generic templates, this is
+ -- harmless.
-- At_End_Proc (Node1)
- -- This field is present in an N_Handled_Sequence_Of_Statements node.
- -- It contains an identifier reference for the cleanup procedure to
- -- be called. See description of this node for further details.
+ -- This field is present in an N_Handled_Sequence_Of_Statements node. It
+ -- contains an identifier reference for the cleanup procedure to be
+ -- called. See description of this node for further details.
-- Backwards_OK (Flag6-Sem)
- -- A flag present in the N_Assignment_Statement node. It is used only
- -- if the type being assigned is an array type, and is set if analysis
+ -- A flag present in the N_Assignment_Statement node. It is used only if
+ -- the type being assigned is an array type, and is set if analysis
-- determines that it is definitely safe to do the copy backwards, i.e.
- -- starting at the highest addressed element. Note that if neither of
- -- the flags Forwards_OK or Backwards_OK is set, it means that the
- -- front end could not determine that either direction is definitely
- -- safe, and a runtime check is required.
+ -- starting at the highest addressed element. Note that if neither of the
+ -- flags Forwards_OK or Backwards_OK is set, it means that the front end
+ -- could not determine that either direction is definitely safe, and a
+ -- runtime check is required.
-- Body_To_Inline (Node3-Sem)
-- present in subprogram declarations. Denotes analyzed but unexpanded
-- which is used directly in later calls to the original subprogram.
-- Body_Required (Flag13-Sem)
- -- A flag that appears in the N_Compilation_Unit node indicating that
- -- the corresponding unit requires a body. For the package case, this
- -- indicates that a completion is required. In Ada 95, if the flag
- -- is not set for the package case, then a body may not be present.
- -- In Ada 83, if the flag is not set for the package case, then a
- -- body is optional. For a subprogram declaration, the flag is set
- -- except in the case where a pragma Import or Interface applies,
- -- in which case no body is permitted (in Ada 83 or Ada 95).
+ -- A flag that appears in the N_Compilation_Unit node indicating that the
+ -- corresponding unit requires a body. For the package case, this
+ -- indicates that a completion is required. In Ada 95, if the flag is not
+ -- set for the package case, then a body may not be present. In Ada 83,
+ -- if the flag is not set for the package case, then body is optional.
+ -- For a subprogram declaration, the flag is set except in the case where
+ -- a pragma Import or Interface applies, in which case no body is
+ -- permitted (in Ada 83 or Ada 95).
-- By_Ref (Flag5-Sem)
-- A flag present in the N_Return_Statement_Node. It is set when the
- -- returned expression is already allocated on the secondary stack
- -- and thus the result is passed by reference rather than copied
- -- another time.
+ -- returned expression is already allocated on the secondary stack and
+ -- thus the result is passed by reference rather than copied another
+ -- time.
-- Check_Address_Alignment (Flag11-Sem)
-- A flag present in N_Attribute_Definition clause for a 'Address
- -- attribute definition. This flag is set if a dynamic check should
- -- be generated at the freeze point for the entity to which this
- -- address clause applies. The reason that we need this flag is that
- -- we want to check for range checks being suppressed at the point
- -- where the attribute definition clause is given, rather than
- -- testing this at the freeze point.
+ -- attribute definition. This flag is set if a dynamic check should be
+ -- generated at the freeze point for the entity to which this address
+ -- clause applies. The reason that we need this flag is that we want to
+ -- check for range checks being suppressed at the point where the
+ -- attribute definition clause is given, rather than testing this at the
+ -- freeze point.
-- Compile_Time_Known_Aggregate (Flag18-Sem)
- -- Present in N_Aggregate nodes. Set for aggregates which can be
- -- fully evaluated at compile time without raising constraint error.
- -- Such aggregates can be passed as is to Gigi without any expansion.
- -- See Sem_Aggr for the specific conditions under which an aggregate
- -- has this flag set. See also the flag Static_Processing_OK.
+ -- Present in N_Aggregate nodes. Set for aggregates which can be fully
+ -- evaluated at compile time without raising constraint error. Such
+ -- aggregates can be passed as is to Gigi without any expansion. See
+ -- Sem_Aggr for the specific conditions under which an aggregate has this
+ -- flag set. See also the flag Static_Processing_OK.
-- Condition_Actions (List3-Sem)
- -- This field appears in else-if nodes and in the iteration scheme
- -- node for while loops. This field is only used during semantic
- -- processing to temporarily hold actions inserted into the tree.
- -- In the tree passed to gigi, the condition actions field is always
- -- set to No_List. For details on how this field is used, see the
- -- routine Insert_Actions in package Exp_Util, and also the expansion
- -- routines for the relevant nodes.
+ -- This field appears in else-if nodes and in the iteration scheme node
+ -- for while loops. This field is only used during semantic processing to
+ -- temporarily hold actions inserted into the tree. In the tree passed to
+ -- gigi, the condition actions field is always set to No_List. For
+ -- details on how this field is used, see the routine Insert_Actions in
+ -- package Exp_Util, and also the expansion routines for the relevant
+ -- nodes.
-- Controlling_Argument (Node1-Sem)
- -- This field is set in procedure and function call nodes if the call
- -- is a dispatching call (it is Empty for a non-dispatching call).
- -- It indicates the source of the controlling tag for the call. For
- -- Procedure calls, the Controlling_Argument is one of the actuals.
- -- For a function that has a dispatching result, it is an entity in
- -- the context of the call that can provide a tag, or else it is the
- -- tag of the root type of the class. It can also specify a tag
- -- directly rather than being a tagged object. The latter is needed
- -- by the implementations of AI-239 and AI-260.
+ -- This field is set in procedure and function call nodes if the call is
+ -- a dispatching call (it is Empty for a non-dispatching call). It
+ -- indicates the source of the call's controlling tag. For procedure
+ -- calls, the Controlling_Argument is one of the actuals. For function
+ -- that has a dispatching result, it is an entity in the context of the
+ -- call that can provide a tag, or else it is the tag of the root type of
+ -- the class. It can also specify a tag directly rather than being a
+ -- tagged object. The latter is needed by the implementations of AI-239
+ -- and AI-260.
-- Conversion_OK (Flag14-Sem)
- -- A flag set on type conversion nodes to indicate that the conversion
- -- is to be considered as being valid, even though it is the case that
- -- the conversion is not valid Ada. This is used for the Enum_Rep,
- -- Fixed_Value and Integer_Value attributes, for internal conversions
- -- done for fixed-point operations, and for certain conversions for
- -- calls to initialization procedures. If Conversion_OK is set, then
- -- Etype must be set (the analyzer assumes that Etype has been set).
- -- For the case of fixed-point operands, it also indicates that the
- -- conversion is to be a direct conversion of the underlying integer
- -- result, with no regard to the small operand.
+ -- A flag set on type conversion nodes to indicate that the conversion is
+ -- to be considered as being valid, even though it is the case that the
+ -- conversion is not valid Ada. This is used for Enum_Rep, Fixed_Value
+ -- and Integer_Value attributes, for internal conversions done for
+ -- fixed-point operations, and for certain conversions for calls to
+ -- initialization procedures. If Conversion_OK is set, then Etype must be
+ -- set (the analyzer assumes that Etype has been set). For the case of
+ -- fixed-point operands, it also indicates that the conversion is to be
+ -- direct conversion of the underlying integer result, with no regard to
+ -- the small operand.
-- Corresponding_Body (Node5-Sem)
-- This field is set in subprogram declarations, package declarations,
-- Corresponding_Spec (Node5-Sem)
-- This field is set in subprogram, package, task, and protected body
-- nodes, where it points to the defining entity in the corresponding
- -- spec. The attribute is also set in N_With_Clause nodes, where
- -- it points to the defining entity for the with'ed spec, and in
- -- a subprogram renaming declaration when it is a Renaming_As_Body.
- -- The field is Empty if there is no corresponding spec, as in the
- -- case of a subprogram body that serves as its own spec.
+ -- spec. The attribute is also set in N_With_Clause nodes, where it
+ -- points to the defining entity for the with'ed spec, and in a
+ -- subprogram renaming declaration when it is a Renaming_As_Body. The
+ -- field is Empty if there is no corresponding spec, as in the case of a
+ -- subprogram body that serves as its own spec.
-- Corresponding_Stub (Node3-Sem)
-- This field is present in an N_Subunit node. It holds the node in
-- for the discriminant checking function for the variant.
-- Debug_Statement (Node3)
- -- This field is present in an N_Pragma node. It is used only for
- -- a Debug pragma or pragma Assert with a second parameter. The
- -- parameter is of the form of an expression, as required by the
- -- pragma syntax, but is actually a procedure call. To simplify
+ -- This field is present in an N_Pragma node. It is used only for a Debug
+ -- pragma. The parameter is of the form of an expression, as required by
+ -- the pragma syntax, but is actually a procedure call. To simplify
-- semantic processing, the parser creates a copy of the argument
-- rearranged into a procedure call statement and places it in the
- -- Debug_Statement field. Note that this field is considered a
- -- syntactic field, since it is created by the parser.
+ -- Debug_Statement field. Note that this field is considered syntactic
+ -- field, since it is created by the parser.
-- Default_Expression (Node5-Sem)
- -- This field is Empty if there is no default expression. If there
- -- is a simple default expression (one with no side effects), then
- -- this field simply contains a copy of the Expression field (both
- -- point to the tree for the default expression). Default_Expression
- -- is used for conformance checking.
+ -- This field is Empty if there is no default expression. If there is a
+ -- simple default expression (one with no side effects), then this field
+ -- simply contains a copy of the Expression field (both point to the tree
+ -- for the default expression). Default_Expression is used for
+ -- conformance checking.
-- Delay_Finalize_Attach (Flag14-Sem)
-- This flag is present in an N_Object_Declaration node. If it is set,
-- then in the case of a controlled type being declared and initialized,
-- the normal code for attaching the result to the appropriate local
-- finalization list is suppressed. This is used for functions that
- -- return controlled types without using the secondary stack, where
- -- it is the caller who must do the attachment.
+ -- return controlled types without using the secondary stack, where it is
+ -- the caller who must do the attachment.
-- Discr_Check_Funcs_Built (Flag11-Sem)
-- This flag is present in N_Full_Type_Declaration nodes. It is set when
-- is required. It is not determined who deals with this flag (???).
-- Do_Overflow_Check (Flag17-Sem)
- -- This flag is set on an operator where an overflow check is required
- -- on the operation. The actual check is dealt with by the backend
- -- (all the front end does is to set the flag). The other cases where
- -- this flag is used is on a Type_Conversion node and for attribute
- -- reference nodes. For a type conversion, it means that the conversion
- -- is from one base type to another, and the value may not fit in the
- -- target base type. See also the description of Do_Range_Check for
- -- this case. The only attribute references which use this flag are
- -- Pred and Succ, where it means that the result should be checked
- -- for going outside the base range.
+ -- This flag is set on an operator where an overflow check is required on
+ -- the operation. The actual check is dealt with by the backend (all the
+ -- front end does is to set the flag). The other cases where this flag is
+ -- used is on a Type_Conversion node and for attribute reference nodes.
+ -- For a type conversion, it means that the conversion is from one base
+ -- type to another, and the value may not fit in the target base type.
+ -- See also the description of Do_Range_Check for this case. The only
+ -- attribute references which use this flag are Pred and Succ, where it
+ -- means that the result should be checked for going outside the base
+ -- range.
-- Do_Range_Check (Flag9-Sem)
-- This flag is set on an expression which appears in a context where
-- target type is determined from the type of the array, which is
-- referenced by the Prefix of the N_Indexed_Component node.
- -- Argument expression for a parameter, appearing either directly
- -- in the Parameter_Associations list of a call or as the Expression
- -- of an N_Parameter_Association node that appears in this list. In
- -- either case, the check is against the type of the formal. Note
- -- that the flag is relevant only in IN and IN OUT parameters, and
- -- will be ignored for OUT parameters, where no check is required
- -- in the call, and if a check is required on the return, it is
- -- generated explicitly with a type conversion.
+ -- Argument expression for a parameter, appearing either directly in
+ -- the Parameter_Associations list of a call or as the Expression of an
+ -- N_Parameter_Association node that appears in this list. In either
+ -- case, the check is against the type of the formal. Note that the
+ -- flag is relevant only in IN and IN OUT parameters, and will be
+ -- ignored for OUT parameters, where no check is required in the call,
+ -- and if a check is required on the return, it is generated explicitly
+ -- with a type conversion.
-- Initialization expression for the initial value in an object
-- declaration. In this case the Do_Range_Check flag is set on
-- the initialization expression, and the check is against the
-- range of the type of the object being declared.
- -- The expression of a type conversion. In this case the range check
- -- is against the target type of the conversion. See also the use of
- -- Do_Overflow_Check on a type conversion. The distinction is that
- -- the overflow check protects against a value that is outside the
- -- range of the target base type, whereas a range check checks that
- -- the resulting value (which is a value of the base type of the
- -- target type), satisfies the range constraint of the target type.
+ -- The expression of a type conversion. In this case the range check is
+ -- against the target type of the conversion. See also the use of
+ -- Do_Overflow_Check on a type conversion. The distinction is that the
+ -- overflow check protects against a value that is outside the range of
+ -- the target base type, whereas a range check checks that the
+ -- resulting value (which is a value of the base type of the target
+ -- type), satisfies the range constraint of the target type.
-- Note: when a range check is required in contexts other than those
-- listed above (e.g. in a return statement), an additional type
-- Do_Storage_Check (Flag17-Sem)
-- This flag is set in an N_Allocator node to indicate that a storage
- -- check is required for the allocation, or in an N_Subprogram_Body
- -- node to indicate that a stack check is required in the subprogram
- -- prolog. The N_Allocator case is handled by the routine that expands
- -- the call to the runtime routine. The N_Subprogram_Body case is
- -- handled by the backend, and all the semantics does is set the flag.
+ -- check is required for the allocation, or in an N_Subprogram_Body node
+ -- to indicate that a stack check is required in the subprogram prolog.
+ -- The N_Allocator case is handled by the routine that expands the call
+ -- to the runtime routine. The N_Subprogram_Body case is handled by the
+ -- backend, and all the semantics does is set the flag.
-- Do_Tag_Check (Flag13-Sem)
-- This flag is set on an N_Assignment_Statement, N_Function_Call,
-- actions at an appropriate place in the tree to get elaborated at the
-- right time. For conditional expressions, we have to be sure that the
-- actions for the Else branch are only elaborated if the condition is
- -- False. The Else_Actions field is used as a temporary parking place
- -- for these actions. The final tree is always rewritten to eliminate
- -- the need for this field, so in the tree passed to Gigi, this field
- -- is always set to No_List.
+ -- False. The Else_Actions field is used as a temporary parking place for
+ -- these actions. The final tree is always rewritten to eliminate the
+ -- need for this field, so in the tree passed to Gigi, this field is
+ -- always set to No_List.
-- Enclosing_Variant (Node2-Sem)
-- This field is present in the N_Variant node and identifies the
-- processing of the variant part of a record type.
-- Entity (Node4-Sem)
- -- Appears in all direct names (identifier, character literal,
- -- operator symbol), as well as expanded names, and attributes that
- -- denote entities, such as 'Class. Points to the entity for the
- -- corresponding defining occurrence. Set after name resolution.
- -- In the case of identifiers in a WITH list, the corresponding
- -- defining occurrence is in a separately compiled file, and this
- -- pointer must be set using the library Load procedure. Note that
- -- during name resolution, the value in Entity may be temporarily
- -- incorrect (e.g. during overload resolution, Entity is initially
- -- set to the first possible correct interpretation, and then later
- -- modified if necessary to contain the correct value after resolution).
- -- Note that this field overlaps Associated_Node, which is used during
- -- generic processing (see Sem_Ch12 for details). Note also that in
- -- generic templates, this means that the Entity field does not always
- -- point to an Entity. Since the back end is expected to ignore
- -- generic templates, this is harmless.
+ -- Appears in all direct names (identifier, character literal, operator
+ -- symbol), as well as expanded names, and attributes that denote
+ -- entities, such as 'Class. Points to the entity for the corresponding
+ -- defining occurrence. Set after name resolution. In the case of
+ -- identifiers in a WITH list, the corresponding defining occurrence is
+ -- in a separately compiled file, and this pointer must be set using the
+ -- library Load procedure. Note that during name resolution, the value in
+ -- Entity may be temporarily incorrect (e.g. during overload resolution,
+ -- Entity is initially set to the first possible correct interpretation,
+ -- and then later modified if necessary to contain the correct value
+ -- after resolution). Note that this field overlaps Associated_Node,
+ -- which is used during generic processing (see Sem_Ch12 for details).
+ -- Note also that in generic templates, this means that the Entity field
+ -- does not always point to an Entity. Since the back end is expected to
+ -- ignore generic templates, this is harmless.
-- Entity_Or_Associated_Node (Node4-Sem)
- -- A synonym for both Entity and Associated_Node. Used by convention
- -- in the code when referencing this field in cases where it is not
- -- known whether the field contains an Entity or an Associated_Node.
+ -- A synonym for both Entity and Associated_Node. Used by convention in
+ -- the code when referencing this field in cases where it is not known
+ -- whether the field contains an Entity or an Associated_Node.
-- Etype (Node5-Sem)
- -- Appears in all expression nodes, all direct names, and all
- -- entities. Points to the entity for the related type. Set after
- -- type resolution. Normally this is the actual subtype of the
- -- expression. However, in certain contexts such as the right side
- -- of an assignment, subscripts, arguments to calls, returned value
- -- in a function, initial value etc. it is the desired target type.
- -- In the event that this is different from the actual type, the
- -- Do_Range_Check flag will be set if a range check is required.
- -- Note: if the Is_Overloaded flag is set, then Etype points to
- -- an essentially arbitrary choice from the possible set of types.
+ -- Appears in all expression nodes, all direct names, and all entities.
+ -- Points to the entity for the related type. Set after type resolution.
+ -- Normally this is the actual subtype of the expression. However, in
+ -- certain contexts such as the right side of an assignment, subscripts,
+ -- arguments to calls, returned value in a function, initial value etc.
+ -- it is the desired target type. In the event that this is different
+ -- from the actual type, the Do_Range_Check flag will be set if a range
+ -- check is required. Note: if the Is_Overloaded flag is set, then Etype
+ -- points to an essentially arbitrary choice from the possible set of
+ -- types.
-- Exception_Junk (Flag7-Sem)
- -- This flag is set in a various nodes appearing in a statement
- -- sequence to indicate that the corresponding node is an artifact
- -- of the generated code for exception handling, and should be
- -- ignored when analyzing the control flow of the relevant sequence
- -- of statements (e.g. to check that it does not end with a bad
- -- return statement).
+ -- This flag is set in a various nodes appearing in a statement sequence
+ -- to indicate that the corresponding node is an artifact of the
+ -- generated code for exception handling, and should be ignored when
+ -- analyzing the control flow of the relevant sequence of statements
+ -- (e.g. to check that it does not end with a bad return statement).
-- Expansion_Delayed (Flag11-Sem)
- -- Set on aggregates and extension aggregates that need a top-down
- -- rather than bottom up expansion. Typically aggregate expansion
- -- happens bottom up. For nested aggregates the expansion is delayed
- -- until the enclosing aggregate itself is expanded, e.g. in the context
- -- of a declaration. To delay it we set this flag. This is done to
- -- avoid creating a temporary for each level of a nested aggregates,
- -- and also to prevent the premature generation of constraint checks.
- -- This is also a requirement if we want to generate the proper
- -- attachment to the internal finalization lists (for record with
- -- controlled components). Top down expansion of aggregates is also
- -- used for in-place array aggregate assignment or initialization.
- -- When the full context is known, the target of the assignment or
- -- initialization is used to generate the left-hand side of individual
- -- assignment to each sub-component.
+ -- Set on aggregates and extension aggregates that need a top-down rather
+ -- than bottom up expansion. Typically aggregate expansion happens bottom
+ -- up. For nested aggregates the expansion is delayed until the enclosing
+ -- aggregate itself is expanded, e.g. in the context of a declaration. To
+ -- delay it we set this flag. This is done to avoid creating a temporary
+ -- for each level of a nested aggregates, and also to prevent the
+ -- premature generation of constraint checks. This is also a requirement
+ -- if we want to generate the proper attachment to the internal
+ -- finalization lists (for record with controlled components). Top down
+ -- expansion of aggregates is also used for in-place array aggregate
+ -- assignment or initialization. When the full context is known, the
+ -- target of the assignment or initialization is used to generate the
+ -- left-hand side of individual assignment to each sub-component.
-- First_Inlined_Subprogram (Node3-Sem)
- -- Present in the N_Compilation_Unit node for the main program. Points
- -- to a chain of entities for subprograms that are to be inlined. The
+ -- Present in the N_Compilation_Unit node for the main program. Points to
+ -- a chain of entities for subprograms that are to be inlined. The
-- Next_Inlined_Subprogram field of these entities is used as a link
- -- pointer with Empty marking the end of the list. This field is Empty
- -- if there are no inlined subprograms or inlining is not active.
+ -- pointer with Empty marking the end of the list. This field is Empty if
+ -- there are no inlined subprograms or inlining is not active.
-- First_Named_Actual (Node4-Sem)
- -- Present in procedure call statement and function call nodes, and
- -- also in Intrinsic nodes. Set during semantic analysis to point to
- -- the first named parameter where parameters are ordered by declaration
- -- order (as opposed to the actual order in the call which may be
- -- different due to named associations). Note: this field points to the
- -- explicit actual parameter itself, not the N_Parameter_Association
- -- node (its parent).
+ -- Present in procedure call statement and function call nodes, and also
+ -- in Intrinsic nodes. Set during semantic analysis to point to the first
+ -- named parameter where parameters are ordered by declaration order (as
+ -- opposed to the actual order in the call which may be different due to
+ -- named associations). Note: this field points to the explicit actual
+ -- parameter itself, not the N_Parameter_Association node (its parent).
-- First_Real_Statement (Node2-Sem)
-- Present in N_Handled_Sequence_Of_Statements node. Normally set to
- -- Empty. Used only when declarations are moved into the statement
- -- part of a construct as a result of wrapping an AT END handler that
- -- is required to cover the declarations. In this case, this field is
- -- used to remember the location in the statements list of the first
- -- real statement, i.e. the statement that used to be first in the
- -- statement list before the declarations were prepended.
+ -- Empty. Used only when declarations are moved into the statement part
+ -- of a construct as a result of wrapping an AT END handler that is
+ -- required to cover the declarations. In this case, this field is used
+ -- to remember the location in the statements list of the first real
+ -- statement, i.e. the statement that used to be first in the statement
+ -- list before the declarations were prepended.
-- First_Subtype_Link (Node5-Sem)
- -- Present in N_Freeze_Entity node for an anonymous base type that
- -- is implicitly created by the declaration of a first subtype. It
- -- points to the entity for the first subtype.
+ -- Present in N_Freeze_Entity node for an anonymous base type that is
+ -- implicitly created by the declaration of a first subtype. It points to
+ -- the entity for the first subtype.
-- Float_Truncate (Flag11-Sem)
- -- A flag present in type conversion nodes. This is used for float
- -- to integer conversions where truncation is required rather than
- -- rounding. Note that Gigi does not handle type conversions from real
- -- to integer with rounding (see Expand_N_Type_Conversion).
+ -- A flag present in type conversion nodes. This is used for float to
+ -- integer conversions where truncation is required rather than rounding.
+ -- Note that Gigi does not handle type conversions from real to integer
+ -- with rounding (see Expand_N_Type_Conversion).
-- Forwards_OK (Flag5-Sem)
- -- A flag present in the N_Assignment_Statement node. It is used only
- -- if the type being assigned is an array type, and is set if analysis
+ -- A flag present in the N_Assignment_Statement node. It is used only if
+ -- the type being assigned is an array type, and is set if analysis
-- determines that it is definitely safe to do the copy forwards, i.e.
- -- starting at the lowest addressed element. Note that if neither of
- -- the flags Forwards_OK or Backwards_OK is set, it means that the
- -- front end could not determine that either direction is definitely
- -- safe, and a runtime check is required.
+ -- starting at the lowest addressed element. Note that if neither of the
+ -- flags Forwards_OK or Backwards_OK is set, it means that the front end
+ -- could not determine that either direction is definitely safe, and a
+ -- runtime check is required.
-- From_At_Mod (Flag4-Sem)
-- This flag is set on the attribute definition clause node that is
-- generated by a transformation of an at mod phrase in a record
- -- representation clause. This is used to give slightly different
- -- (Ada 83 compatible) semantics to such a clause, namely it is
- -- used to specify a minimum acceptable alignment for the base type
- -- and all subtypes. In Ada 95 terms, the actual alignment of the
- -- base type and all subtypes must be a multiple of the given value,
- -- and the representation clause is considered to be type specific
- -- instead of subtype specific.
+ -- representation clause. This is used to give slightly different (Ada 83
+ -- compatible) semantics to such a clause, namely it is used to specify a
+ -- minimum acceptable alignment for the base type and all subtypes. In
+ -- Ada 95 terms, the actual alignment of the base type and all subtypes
+ -- must be a multiple of the given value, and the representation clause
+ -- is considered to be type specific instead of subtype specific.
-- From_Default (Flag6-Sem)
- -- This flag is set on the subprogram renaming declaration created in
- -- an instance for a formal subprogram, when the formal is declared
- -- with a box, and there is no explicit actual. If the flag is present,
- -- the declaration is treated as an implicit reference to the formal in
- -- the ali file.
+ -- This flag is set on the subprogram renaming declaration created in an
+ -- instance for a formal subprogram, when the formal is declared with a
+ -- box, and there is no explicit actual. If the flag is present, the
+ -- declaration is treated as an implicit reference to the formal in the
+ -- ali file.
-- Generic_Parent (Node5-Sem)
- -- Generic_parent is defined on declaration nodes that are instances.
- -- The value of Generic_Parent is the generic entity from which the
- -- instance is obtained. Generic_Parent is also defined for the renaming
+ -- Generic_parent is defined on declaration nodes that are instances. The
+ -- value of Generic_Parent is the generic entity from which the instance
+ -- is obtained. Generic_Parent is also defined for the renaming
-- declarations and object declarations created for the actuals in an
-- instantiation. The generic parent of such a declaration is the
-- corresponding generic association in the Instantiation node.
-- Generic_Parent_Type (Node4-Sem)
- -- Generic_Parent_Type is defined on Subtype_Declaration nodes for
- -- the actuals of formal private and derived types. Within the instance,
- -- the operations on the actual are those inherited from the parent.
- -- For a formal private type, the parent type is the generic type
- -- itself. The Generic_Parent_Type is also used in an instance to
- -- determine whether a private operation overrides an inherited one.
+ -- Generic_Parent_Type is defined on Subtype_Declaration nodes for the
+ -- actuals of formal private and derived types. Within the instance, the
+ -- operations on the actual are those inherited from the parent. For a
+ -- formal private type, the parent type is the generic type itself. The
+ -- Generic_Parent_Type is also used in an instance to determine whether a
+ -- private operation overrides an inherited one.
-- Handler_List_Entry (Node2-Sem)
-- This field is present in N_Object_Declaration nodes. It is set only
-- this is required, see Exp_Ch11.Remove_Handler_Entries.
-- Has_No_Elaboration_Code (Flag17-Sem)
- -- A flag that appears in the N_Compilation_Unit node to indicate
- -- whether or not elaboration code is present for this unit. It is
- -- initially set true for subprogram specs and bodies and for all
- -- generic units and false for non-generic package specs and bodies.
- -- Gigi may set the flag in the non-generic package case if it
- -- determines that no elaboration code is generated. Note that this
- -- flag is not related to the Is_Preelaborated status, there can be
- -- preelaborated packages that generate elaboration code, and non-
- -- preelaborated packages which do not generate elaboration code.
+ -- A flag that appears in the N_Compilation_Unit node to indicate whether
+ -- or not elaboration code is present for this unit. It is initially set
+ -- true for subprogram specs and bodies and for all generic units and
+ -- false for non-generic package specs and bodies. Gigi may set the flag
+ -- in the non-generic package case if it determines that no elaboration
+ -- code is generated. Note that this flag is not related to the
+ -- Is_Preelaborated status, there can be preelaborated packages that
+ -- generate elaboration code, and non- preelaborated packages which do
+ -- not generate elaboration code.
-- Has_Priority_Pragma (Flag6-Sem)
-- A flag present in N_Subprogram_Body, N_Task_Definition and
- -- N_Protected_Definition nodes to flag the presence of either
- -- a Priority or Interrupt_Priority pragma in the declaration
- -- sequence (public or private in the task and protected cases)
+ -- N_Protected_Definition nodes to flag the presence of either a Priority
+ -- or Interrupt_Priority pragma in the declaration sequence (public or
+ -- private in the task and protected cases)
-- Has_Private_View (Flag11-Sem)
- -- A flag present in generic nodes that have an entity, to indicate
- -- that the node has a private type. Used to exchange private
- -- and full declarations if the visibility at instantiation is
- -- different from the visibility at generic definition.
+ -- A flag present in generic nodes that have an entity, to indicate that
+ -- the node has a private type. Used to exchange private and full
+ -- declarations if the visibility at instantiation is different from the
+ -- visibility at generic definition.
-- Has_Storage_Size_Pragma (Flag5-Sem)
- -- A flag present in an N_Task_Definition node to flag the presence
- -- of a Storage_Size pragma
+ -- A flag present in an N_Task_Definition node to flag the presence of a
+ -- Storage_Size pragma.
-- Has_Task_Info_Pragma (Flag7-Sem)
- -- A flag present in an N_Task_Definition node to flag the presence
- -- of a Task_Info pragma. Used to detect duplicate pragmas.
+ -- A flag present in an N_Task_Definition node to flag the presence of a
+ -- Task_Info pragma. Used to detect duplicate pragmas.
-- Has_Task_Name_Pragma (Flag8-Sem)
- -- A flag present in N_Task_Definition nodes to flag the presence
- -- of a Task_Name pragma in the declaration sequence for the task.
+ -- A flag present in N_Task_Definition nodes to flag the presence of a
+ -- Task_Name pragma in the declaration sequence for the task.
-- Has_Wide_Character (Flag11-Sem)
- -- Present in string literals, set if any wide character (i.e. a
- -- character code outside the Character range) appears in the string.
+ -- Present in string literals, set if any wide character (i.e. character
+ -- code outside the Character range) appears in the string.
-- Hidden_By_Use_Clause (Elist4-Sem)
-- An entity list present in use clauses that appear within
-- instantiations. For the resolution of local entities, entities
- -- introduced by these use clauses have priority over global ones,
- -- and outer entities must be explicitly hidden/restored on exit.
+ -- introduced by these use clauses have priority over global ones, and
+ -- outer entities must be explicitly hidden/restored on exit.
-- Implicit_With (Flag16-Sem)
-- This flag is set in the N_With_Clause node that is implicitly
- -- generated for runtime units that are loaded by the expander, and
- -- also for package System, if it is loaded implicitly by a use of
- -- the 'Address or 'Tag attribute
+ -- generated for runtime units that are loaded by the expander, and also
+ -- for package System, if it is loaded implicitly by a use of the
+ -- 'Address or 'Tag attribute.
-- Includes_Infinities (Flag11-Sem)
- -- This flag is present in N_Range nodes. It is set for the range
- -- of unconstrained float types defined in Standard, which include
- -- not only the given range of values, but also legtitimately can
- -- include infinite values. This flag is false for any float type
- -- for which an explicit range is given by the programmer, even if
- -- that range is identical to the range for float.
+ -- This flag is present in N_Range nodes. It is set for the range of
+ -- unconstrained float types defined in Standard, which include not only
+ -- the given range of values, but also legtitimately can include infinite
+ -- values. This flag is false for any float type for which an explicit
+ -- range is given by the programmer, even if that range is identical to
+ -- the range for Float.
-- Instance_Spec (Node5-Sem)
-- This field is present in generic instantiation nodes, and also in
-- formal package declaration nodes (formal package declarations are
- -- treated in a manner very similar to package instantiations). It
- -- points to the node for the spec of the instance, inserted as part
- -- of the semantic processing for instantiations in Sem_Ch12.
+ -- treated in a manner very similar to package instantiations). It points
+ -- to the node for the spec of the instance, inserted as part of the
+ -- semantic processing for instantiations in Sem_Ch12.
-- Is_Asynchronous_Call_Block (Flag7-Sem)
-- A flag set in a Block_Statement node to indicate that it is the
- -- expansion of an asynchronous entry call. Such a block needs a
- -- cleanup handler to assure that the call is cancelled.
+ -- expansion of an asynchronous entry call. Such a block needs cleanup
+ -- handler to assure that the call is cancelled.
-- Is_Component_Left_Opnd (Flag13-Sem)
-- Is_Component_Right_Opnd (Flag14-Sem)
-- concatenation nodes in instances.
-- Is_Controlling_Actual (Flag16-Sem)
- -- This flag is set on in an expression that is a controlling argument
- -- in a dispatching call. It is off in all other cases. See Sem_Disp
- -- for details of its use.
+ -- This flag is set on in an expression that is a controlling argument in
+ -- a dispatching call. It is off in all other cases. See Sem_Disp for
+ -- details of its use.
-- Is_In_Discriminant_Check (Flag11-Sem)
- -- This flag is present in a selected component, and is used to
- -- indicate that the reference occurs within a discriminant check.
- -- The significance is that optimizations based on assuming that
- -- the discriminant check has a correct value cannot be performed
- -- in this case (or the disriminant check may be optimized away!)
+ -- This flag is present in a selected component, and is used to indicate
+ -- that the reference occurs within a discriminant check. The
+ -- significance is that optimizations based on assuming that the
+ -- discriminant check has a correct value cannot be performed in this
+ -- case (or the disriminant check may be optimized away!)
-- Is_Machine_Number (Flag11-Sem)
- -- This flag is set in an N_Real_Literal node to indicate that the
- -- value is a machine number. This avoids some unnecessary cases
- -- of converting real literals to machine numbers.
+ -- This flag is set in an N_Real_Literal node to indicate that the value
+ -- is a machine number. This avoids some unnecessary cases of converting
+ -- real literals to machine numbers.
-- Is_Null_Loop (Flag16-Sem)
- -- This flag is set in an N_Loop_Statement node if the corresponding
- -- loop can be determined to be null at compile time. This is used to
- -- suppress any warnings that would otherwise be issued inside the
- -- loop since they are probably not useful.
+ -- This flag is set in an N_Loop_Statement node if the corresponding loop
+ -- can be determined to be null at compile time. This is used to suppress
+ -- any warnings that would otherwise be issued inside the loop since they
+ -- are probably not useful.
-- Is_Overloaded (Flag5-Sem)
-- A flag present in all expression nodes. Used temporarily during
- -- overloading determination. The setting of this flag is not
- -- relevant once overloading analysis is complete.
+ -- overloading determination. The setting of this flag is not relevant
+ -- once overloading analysis is complete.
-- Is_Power_Of_2_For_Shift (Flag13-Sem)
-- A flag present only in N_Op_Expon nodes. It is set when the
- -- exponentiation is of the forma 2 ** N, where the type of N is
- -- an unsigned integral subtype whose size does not exceed the size
- -- of Standard_Integer (i.e. a type that can be safely converted to
- -- Natural), and the exponentiation appears as the right operand of
- -- an integer multiplication or an integer division where the dividend
- -- is unsigned. It is also required that overflow checking is off for
- -- both the exponentiation and the multiply/divide node. If this set
- -- of conditions holds, and the flag is set, then the division or
+ -- exponentiation is of the forma 2 ** N, where the type of N is an
+ -- unsigned integral subtype whose size does not exceed the size of
+ -- Standard_Integer (i.e. a type that can be safely converted to
+ -- Natural), and the exponentiation appears as the right operand of an
+ -- integer multiplication or an integer division where the dividend is
+ -- unsigned. It is also required that overflow checking is off for both
+ -- the exponentiation and the multiply/divide node. If this set of
+ -- conditions holds, and the flag is set, then the division or
-- multiplication can be (and is) converted to a shift.
-- Is_Overloaded (Flag5-Sem)
-- A flag present in all expression nodes. Used temporarily during
- -- overloading determination. The setting of this flag is not
- -- relevant once overloading analysis is complete.
+ -- overloading determination. The setting of this flag is not relevant
+ -- once overloading analysis is complete.
-- Is_Protected_Subprogram_Body (Flag7-Sem)
-- A flag set in a Subprogram_Body block to indicate that it is the
- -- implemenation of a protected subprogram. Such a body needs a
- -- cleanup handler to make sure that the associated protected object
- -- is unlocked when the subprogram completes.
+ -- implemenation of a protected subprogram. Such a body needs cleanup
+ -- handler to make sure that the associated protected object is unlocked
+ -- when the subprogram completes.
-- Is_Static_Expression (Flag6-Sem)
- -- Indicates that an expression is a static expression (RM 4.9). See
- -- spec of package Sem_Eval for full details on the use of this flag.
+ -- Indicates that an expression is a static expression (RM 4.9). See spec
+ -- of package Sem_Eval for full details on the use of this flag.
-- Is_Subprogram_Descriptor (Flag16-Sem)
-- Present in N_Object_Declaration, and set only for the object
-- allocated but not activated when the allocator completes abnormally.
-- Is_Task_Master (Flag5-Sem)
- -- A flag set in a Subprogram_Body, Block_Statement or Task_Body node
- -- to indicate that the construct is a task master (i.e. has declared
- -- tasks or declares an access to a task type).
+ -- A flag set in a Subprogram_Body, Block_Statement or Task_Body node to
+ -- indicate that the construct is a task master (i.e. has declared tasks
+ -- or declares an access to a task type).
-- Itype (Node1-Sem)
- -- Used in N_Itype_Reference node to reference an itype for which it
- -- is important to ensure that it is defined. See description of this
- -- node for further details.
+ -- Used in N_Itype_Reference node to reference an itype for which it is
+ -- important to ensure that it is defined. See description of this node
+ -- for further details.
-- Kill_Range_Check (Flag11-Sem)
-- Used in an N_Unchecked_Type_Conversion node to indicate that the
- -- result should not be subjected to range checks. This is used for
- -- the implementation of Normalize_Scalars.
+ -- result should not be subjected to range checks. This is used for the
+ -- implementation of Normalize_Scalars.
-- Label_Construct (Node2-Sem)
-- Used in an N_Implicit_Label_Declaration node. Refers to an N_Label,
-- itself, but it is useful in the implementation of ASIS queries.
-- Library_Unit (Node4-Sem)
- -- In a stub node, the Library_Unit field points to the compilation unit
- -- node of the corresponding subunit.
+ -- In a stub node, Library_Unit points to the compilation unit node of
+ -- the corresponding subunit.
--
- -- In a with clause node, the Library_Unit field points to the spec
- -- of the with'ed unit.
+ -- In a with clause node, Library_Unit points to the spec of the with'ed
+ -- unit.
--
- -- In a compilation unit node, the use of this field depends on
- -- the unit type:
+ -- In a compilation unit node, the usage depends on the unit type:
--
- -- For a subprogram body, the Library_Unit field points to the
- -- compilation unit node of the corresponding spec, unless
- -- Acts_As_Spec is set, in which case it points to itself.
+ -- For a subprogram body, Library_Unit points to the compilation unit
+ -- node of the corresponding spec, unless Acts_As_Spec is set, in which
+ -- case it points to itself.
--
- -- For a package body, the Library_Unit field points to the
- -- compilation unit node of the corresponding spec.
+ -- For a package body, Library_Unit points to the compilation unit of
+ -- the corresponding package spec.
--
- -- For a subprogram spec to which pragma Inline applies, the
- -- Library_Unit field points to the compilation unit node of
- -- the corresponding body, if inlining is active.
+ -- For a subprogram spec to which pragma Inline applies, Library_Unit
+ -- points to the compilation unit node of the corresponding body, if
+ -- inlining is active.
--
- -- For a generic declaration, the Library_Unit field points
- -- to the compilation unit node of the corresponding generic body.
+ -- For a generic declaration, Library_Unit points to the compilation
+ -- unit node of the corresponding generic body.
--
- -- For a subunit, the Library_Unit field points to the compilation
- -- unit node of the parent body.
+ -- For a subunit, Library_Unit points to the compilation unit node of
+ -- the parent body.
--
- -- Note that this field is not used to hold the parent pointer for a
- -- child unit (which might in any case need to use it for some other
- -- purpose as described above). Instead for a child unit, implicit
- -- with's are generated for all parents.
+ -- Note that this field is not used to hold the parent pointer for child
+ -- unit (which might in any case need to use it for some other purpose as
+ -- described above). Instead for a child unit, implicit with's are
+ -- generated for all parents.
-- Loop_Actions (List2-Sem)
-- A list present in Component_Association nodes in array aggregates.
-- they may need to be evaluated anew each time through.
-- Limited_View_Installed (Flag18-Sem)
- -- Present in With_Clauses and in package specifications. If set on a
+ -- Present in With_Clauses and in package specifications. If set on
-- with_clause, it indicates that this clause has created the current
- -- limited view of the designated package. On a package specification,
- -- it indicates that the limited view has already been created because
- -- the package is mentioned in a limited_with_clause in the closure of
- -- the unit being compiled.
+ -- limited view of the designated package. On a package specification, it
+ -- indicates that the limited view has already been created because the
+ -- package is mentioned in a limited_with_clause in the closure of the
+ -- unit being compiled.
-- Must_Be_Byte_Aligned (Flag14-Sem)
-- This flag is present in N_Attribute_Reference nodes. It can be set
-- only for the Address and Unrestricted_Access attributes. If set it
- -- means that the object for which the address/access is given must be
- -- on a byte (more accurately a storage unit) boundary. If necessary,
- -- a copy of the object is to be made before taking the address (this
- -- copy is in the current scope on the stack frame). This is used for
- -- certain cases of code generated by the expander that passes
- -- parameters by address.
+ -- means that the object for which the address/access is given must be on
+ -- a byte (more accurately a storage unit) boundary. If necessary, a copy
+ -- of the object is to be made before taking the address (this copy is in
+ -- the current scope on the stack frame). This is used for certain cases
+ -- of code generated by the expander that passes parameters by address.
--
- -- The reason the copy is not made by the front end is that the back
- -- end has more information about type layout and may be able to (but
- -- is not guaranteed to) prevent making unnecessary copies.
+ -- The reason the copy is not made by the front end is that the back end
+ -- has more information about type layout and may be able to (but is not
+ -- guaranteed to) prevent making unnecessary copies.
-- Must_Not_Freeze (Flag8-Sem)
-- A flag present in all expression nodes. Normally expressions cause
- -- freezing as described in the RM. If this flag is set, then this
- -- is inhibited. This is used by the analyzer and expander to label
- -- nodes that are created by semantic analysis or expansion and which
- -- must not cause freezing even though they normally would. This flag
- -- is also present in an N_Subtype_Indication node, since we also use
- -- these in calls to Freeze_Expression.
+ -- freezing as described in the RM. If this flag is set, then this is
+ -- inhibited. This is used by the analyzer and expander to label nodes
+ -- that are created by semantic analysis or expansion and which must not
+ -- cause freezing even though they normally would. This flag is also
+ -- present in an N_Subtype_Indication node, since we also use these in
+ -- calls to Freeze_Expression.
-- Next_Entity (Node2-Sem)
-- Present in defining identifiers, defining character literals and
- -- defining operator symbols (i.e. in all entities). The entities of
- -- a scope are chained, and this field is used as the forward pointer
- -- for this list. See Einfo for further details.
+ -- defining operator symbols (i.e. in all entities). The entities of a
+ -- scope are chained, and this field is used as the forward pointer for
+ -- this list. See Einfo for further details.
-- Next_Named_Actual (Node4-Sem)
- -- Present in parameter association node. Set during semantic
- -- analysis to point to the next named parameter, where parameters
- -- are ordered by declaration order (as opposed to the actual order
- -- in the call, which may be different due to named associations).
- -- Not that this field points to the explicit actual parameter itself,
- -- not to the N_Parameter_Association node (its parent).
+ -- Present in parameter association node. Set during semantic analysis to
+ -- point to the next named parameter, where parameters are ordered by
+ -- declaration order (as opposed to the actual order in the call, which
+ -- may be different due to named associations). Not that this field
+ -- points to the explicit actual parameter itself, not to the
+ -- N_Parameter_Association node (its parent).
-- Next_Rep_Item (Node4-Sem)
- -- Present in pragma nodes and attribute definition nodes. Used to
- -- link representation items that apply to an entity. See description
- -- of First_Rep_Item field in Einfo for full details.
+ -- Present in pragma nodes and attribute definition nodes. Used to link
+ -- representation items that apply to an entity. See description of
+ -- First_Rep_Item field in Einfo for full details.
-- Next_Use_Clause (Node3-Sem)
- -- While use clauses are active during semantic processing, they
- -- are chained from the scope stack entry, using Next_Use_Clause
- -- as a link pointer, with Empty marking the end of the list. The
- -- head pointer is in the scope stack entry (First_Use_Clause). At
- -- the end of semantic processing (i.e. when Gigi sees the tree,
- -- the contents of this field is undefined and should not be read).
+ -- While use clauses are active during semantic processing, they are
+ -- chained from the scope stack entry, using Next_Use_Clause as a link
+ -- pointer, with Empty marking the end of the list. The head pointer is
+ -- in the scope stack entry (First_Use_Clause). At the end of semantic
+ -- processing (i.e. when Gigi sees the tree, the contents of this field
+ -- is undefined and should not be read).
-- No_Ctrl_Actions (Flag7-Sem)
- -- Present in N_Assignment_Statement to indicate that no finalize nor
- -- nor adjust should take place on this assignment eventhough the rhs
- -- is controlled. This is used in init procs and aggregate expansions
- -- where the generated assignments are more initialisations than real
+ -- Present in N_Assignment_Statement to indicate that no finalize nor nor
+ -- adjust should take place on this assignment eventhough the rhs is
+ -- controlled. This is used in init procs and aggregate expansions where
+ -- the generated assignments are more initialisations than real
-- assignments.
-- No_Elaboration_Check (Flag14-Sem)
-- Present in N_Function_Call and N_Procedure_Call_Statement. Indicates
- -- that no elaboration check is needed on the call, because it appears
- -- in the context of a local Suppress pragma. This is used on calls
- -- within task bodies, where the actual elaboration checks are applied
- -- after analysis, when the local scope stack is not present.
+ -- that no elaboration check is needed on the call, because it appears in
+ -- the context of a local Suppress pragma. This is used on calls within
+ -- task bodies, where the actual elaboration checks are applied after
+ -- analysis, when the local scope stack is not present.
-- No_Entities_Ref_In_Spec (Flag8-Sem)
-- Present in N_With_Clause nodes. Set if the with clause is on the
-- full details)
-- No_Initialization (Flag13-Sem)
- -- Present in N_Object_Declaration & N_Allocator to indicate
- -- that the object must not be initialized (by Initialize or a
- -- call to an init proc). This is needed for controlled aggregates.
- -- When the Object declaration has an expression, this flag means
- -- that this expression should not be taken into account (needed
- -- for in place initialization with aggregates)
+ -- Present in N_Object_Declaration & N_Allocator to indicate that the
+ -- object must not be initialized (by Initialize or call to an init
+ -- proc). This is needed for controlled aggregates. When the Object
+ -- declaration has an expression, this flag means that this expression
+ -- should not be taken into account (needed for in place initialization
+ -- with aggregates)
-- No_Truncation (Flag17-Sem)
-- Present in N_Unchecked_Type_Conversion node. This flag has an effect
-- target for scalar operands. Normally in such a case we truncate some
-- higher order bits of the source, and then sign/zero extend the result
-- to form the output value. But if this flag is set, then we do not do
- -- any truncation, so for example, if an 8 bit input is converted to a
- -- 5 bit result which is in fact stored in 8 bits, then the high order
+ -- any truncation, so for example, if an 8 bit input is converted to 5
+ -- bit result which is in fact stored in 8 bits, then the high order
-- three bits of the target result will be copied from the source. This
-- is used for properly setting out of range values for use by pragmas
-- Initialize_Scalars and Normalize_Scalars.
-- Original_Discriminant (Node2-Sem)
-- Present in identifiers. Used in references to discriminants that
- -- appear in generic units. Because the names of the discriminants
- -- may be different in an instance, we use this field to recover the
- -- position of the discriminant in the original type, and replace it
- -- with the discriminant at the same position in the instantiated type.
+ -- appear in generic units. Because the names of the discriminants may be
+ -- different in an instance, we use this field to recover the position of
+ -- the discriminant in the original type, and replace it with the
+ -- discriminant at the same position in the instantiated type.
-- Original_Entity (Node2-Sem)
- -- Present in numeric literals. Used to denote the named number that
- -- has been constant-folded into the given literal. If literal is from
+ -- Present in numeric literals. Used to denote the named number that has
+ -- been constant-folded into the given literal. If literal is from
-- source, or the result of some other constant-folding operation, then
-- Original_Entity is empty. This field is needed to handle properly
-- named numbers in generic units, where the Associated_Node field
- -- interferes with the Entity field, making it impossible to preserve
- -- the original entity at the point of instantiation (ASIS problem).
+ -- interferes with the Entity field, making it impossible to preserve the
+ -- original entity at the point of instantiation (ASIS problem).
-- Others_Discrete_Choices (List1-Sem)
-- When a case statement or variant is analyzed, the semantic checks
-- determine the actual list of choices that correspond to an others
- -- choice. This list is materialized for later use by the expander
- -- and the Others_Discrete_Choices field of an N_Others_Choice node
- -- points to this materialized list of choices, which is in standard
- -- format for a list of discrete choices, except that of course it
- -- cannot contain an N_Others_Choice entry.
+ -- choice. This list is materialized for later use by the expander and
+ -- the Others_Discrete_Choices field of an N_Others_Choice node points to
+ -- this materialized list of choices, which is in standard format for a
+ -- list of discrete choices, except that of course it cannot contain an
+ -- N_Others_Choice entry.
-- Parameter_List_Truncated (Flag17-Sem)
- -- Present in N_Function_Call and N_Procedure_Call_Statement nodes.
- -- Set (for OpenVMS ports of GNAT only) if the parameter list is
- -- truncated as a result of a First_Optional_Parameter specification
- -- in an Import_Function, Import_Procedure, or Import_Valued_Procedure
- -- pragma. The truncation is done by the expander by removing trailing
- -- parameters from the argument list, in accordance with the set of
- -- rules allowing such parameter removal. In particular, parameters
- -- can be removed working from the end of the parameter list backwards
- -- up to and including the entry designated by First_Optional_Parameter
- -- in the Import pragma. Parameters can be removed if they are implicit
- -- and the default value is a known-at-compile-time value, including
- -- the use of the Null_Parameter attribute, or if explicit parameter
- -- values are present that match the corresponding defaults.
+ -- Present in N_Function_Call and N_Procedure_Call_Statement nodes. Set
+ -- (for OpenVMS ports of GNAT only) if the parameter list is truncated as
+ -- a result of a First_Optional_Parameter specification in an
+ -- Import_Function, Import_Procedure, or Import_Valued_Procedure pragma.
+ -- The truncation is done by the expander by removing trailing parameters
+ -- from the argument list, in accordance with the set of rules allowing
+ -- such parameter removal. In particular, parameters can be removed
+ -- working from the end of the parameter list backwards up to and
+ -- including the entry designated by First_Optional_Parameter in the
+ -- Import pragma. Parameters can be removed if they are implicit and the
+ -- default value is a known-at-compile-time value, including the use of
+ -- the Null_Parameter attribute, or if explicit parameter values are
+ -- present that match the corresponding defaults.
-- Parent_Spec (Node4-Sem)
-- For a library unit that is a child unit spec (package or subprogram
-- Present_Expr (Uint3-Sem)
-- Present in an N_Variant node. This has a meaningful value only after
- -- Gigi has back annotated the tree with representation information.
- -- At this point, it contains a reference to a gcc expression that
- -- depends on the values of one or more discriminants. Give a set of
- -- discriminant values, this expression evaluates to False (zero) if
- -- variant is not present, and True (non-zero) if it is present. See
- -- unit Repinfo for further details on gigi back annotation. This
- -- field is used during ASIS processing (data decomposition annex)
- -- to determine if a field is present or not.
+ -- Gigi has back annotated the tree with representation information. At
+ -- this point, it contains a reference to a gcc expression that depends
+ -- on the values of one or more discriminants. Give a set of discriminant
+ -- values, this expression evaluates to False (zero) if variant is not
+ -- present, and True (non-zero) if it is present. See unit Repinfo for
+ -- further details on gigi back annotation. This field is used during
+ -- ASIS processing (data decomposition annex) to determine if a field is
+ -- present or not.
-- Print_In_Hex (Flag13-Sem)
- -- Set on an N_Integer_Literal node to indicate that the value should
- -- be printed in hexadecimal in the sprint listing. Has no effect on
- -- legality or semantics of program, only on the displayed output.
- -- This is used to clarify output from the packed array cases.
+ -- Set on an N_Integer_Literal node to indicate that the value should be
+ -- printed in hexadecimal in the sprint listing. Has no effect on
+ -- legality or semantics of program, only on the displayed output. This
+ -- is used to clarify output from the packed array cases.
-- Procedure_To_Call (Node4-Sem)
-- Present in N_Allocator, N_Free_Statement, and N_Return_Statement
- -- nodes. References the entity for the declaration of the procedure
- -- to be called to accomplish the required operation (i.e. for the
- -- Allocate procedure in the case of N_Allocator and N_Return_Statement
- -- (for allocating the return value), and for the Deallocate procedure
- -- in the case of N_Free_Statement.
+ -- nodes. References the entity for the declaration of the procedure to
+ -- be called to accomplish the required operation (i.e. for the Allocate
+ -- procedure in the case of N_Allocator and N_Return_Statement (for
+ -- allocating the return value), and for the Deallocate procedure in the
+ -- case of N_Free_Statement.
-- Raises_Constraint_Error (Flag7-Sem)
- -- Set on an expression whose evaluation will definitely fail a
- -- constraint error check. In the case of static expressions, this
- -- flag must be set accurately (and if it is set, the expression is
- -- typically illegal unless it appears as a non-elaborated branch of
- -- a short-circuit form). For a non-static expression, this flag may
- -- be set whenever an expression (e.g. an aggregate) is known to raise
- -- constraint error. If set, the expression definitely will raise CE
- -- if elaborated at runtime. If not set, the expression may or may
- -- not raise CE. In other words, on static expressions, the flag is
- -- set accurately, on non-static expressions it is set conservatively.
+ -- Set on an expression whose evaluation will definitely fail constraint
+ -- error check. In the case of static expressions, this flag must be set
+ -- accurately (and if it is set, the expression is typically illegal
+ -- unless it appears as a non-elaborated branch of a short-circuit form).
+ -- For a non-static expression, this flag may be set whenever an
+ -- expression (e.g. an aggregate) is known to raise constraint error. If
+ -- set, the expression definitely will raise CE if elaborated at runtime.
+ -- If not set, the expression may or may not raise CE. In other words, on
+ -- static expressions, the flag is set accurately, on non-static
+ -- expressions it is set conservatively.
-- Redundant_Use (Flag13-Sem)
- -- A flag present in nodes that can appear as an operand in a use
- -- clause or use type clause (identifiers, expanded names, attribute
- -- references). Set to indicate that a use is redundant (and therefore
- -- need not be undone on scope exit).
+ -- Present in nodes that can appear as an operand in a use clause or use
+ -- type clause (identifiers, expanded names, attribute references). Set
+ -- to indicate that a use is redundant (and therefore need not be undone
+ -- on scope exit).
-- Return_Type (Node2-Sem)
- -- Present in N_Return_Statement node. For a procedure, this is set
- -- to Standard_Void_Type. For a function it references the entity
- -- for the returned type.
+ -- Present in N_Return_Statement node. For a procedure, this is set to
+ -- Standard_Void_Type. For a function it references the entity for the
+ -- returned type.
-- Rounded_Result (Flag18-Sem)
-- Present in N_Type_Conversion, N_Op_Divide and N_Op_Multiply nodes.
-- Used in the fixed-point cases to indicate that the result must be
- -- rounded as a result of the use of the 'Round attribute. Also used
- -- for integer N_Op_Divide nodes to indicate that the result should
- -- be rounded to the nearest integer (breaking ties away from zero),
- -- rather than truncated towards zero as usual. These rounded integer
- -- operations are the result of expansion of rounded fixed-point
- -- divide, conversion and multiplication operations.
+ -- rounded as a result of the use of the 'Round attribute. Also used for
+ -- integer N_Op_Divide nodes to indicate that the result should be
+ -- rounded to the nearest integer (breaking ties away from zero), rather
+ -- than truncated towards zero as usual. These rounded integer operations
+ -- are the result of expansion of rounded fixed-point divide, conversion
+ -- and multiplication operations.
-- Scope (Node3-Sem)
-- Present in defining identifiers, defining character literals and
- -- defining operator symbols (i.e. in all entities). The entities of
- -- a scope all use this field to reference the corresponding scope
- -- entity. See Einfo for further details.
+ -- defining operator symbols (i.e. in all entities). The entities of a
+ -- scope all use this field to reference the corresponding scope entity.
+ -- See Einfo for further details.
-- Shift_Count_OK (Flag4-Sem)
-- A flag present in shift nodes to indicate that the shift count is
-- Static_Processing_OK (Flag4-Sem)
-- Present in N_Aggregate nodes. When the Compile_Time_Known_Aggregate
-- flag is set, the full value of the aggregate can be determined at
- -- compile time and the aggregate can be passed as is to the back-end.
- -- In this event it is irrelevant whether this flag is set or not.
- -- However, if the Compile_Time_Known_Aggregate flag is not set but
+ -- compile time and the aggregate can be passed as is to the back-end. In
+ -- this event it is irrelevant whether this flag is set or not. However,
+ -- if the Compile_Time_Known_Aggregate flag is not set but
-- Static_Processing_OK is set, the aggregate can (but need not) be
- -- converted into a compile time known aggregate by the expander.
- -- See Sem_Aggr for the specific conditions under which an aggregate
- -- has its Static_Processing_OK flag set.
+ -- converted into a compile time known aggregate by the expander. See
+ -- Sem_Aggr for the specific conditions under which an aggregate has its
+ -- Static_Processing_OK flag set.
-- Storage_Pool (Node1-Sem)
- -- Present in N_Allocator, N_Free_Statement and N_Return_Statement
- -- nodes. References the entity for the storage pool to be used for
- -- the allocate or free call or for the allocation of the returned
- -- value from a function. Empty indicates that the global default
- -- default pool is to be used. Note that in the case of a return
- -- statement, this field is set only if the function returns a
- -- value of a type whose size is not known at compile time on the
- -- secondary stack. It is never set on targets for which the target
- -- parameter Targparm.Functions_Return_By_DSP_On_Target is True.
+ -- Present in N_Allocator, N_Free_Statement and N_Return_Statement nodes.
+ -- References the entity for the storage pool to be used for the allocate
+ -- or free call or for the allocation of the returned value from a
+ -- function. Empty indicates that the global default default pool is to
+ -- be used. Note that in the case of a return statement, this field is
+ -- set only if the function returns value of a type whose size is not
+ -- known at compile time on the secondary stack. It is never set on
+ -- targets for which the parameter Functions_Return_By_DSP_On_Target in
+ -- Targparm is True.
-- Target_Type (Node2-Sem)
- -- Used in an N_Validate_Unchecked_Conversion node to point to the
- -- target type entity for the unchecked conversion instantiation
- -- which gigi must do size validation for.
+ -- Used in an N_Validate_Unchecked_Conversion node to point to the target
+ -- type entity for the unchecked conversion instantiation which gigi must
+ -- do size validation for.
-- Then_Actions (List3-Sem)
-- This field is present in conditional expression nodes. During code
-- actions at an appropriate place in the tree to get elaborated at the
-- right time. For conditional expressions, we have to be sure that the
-- actions for the Then branch are only elaborated if the condition is
- -- True. The Then_Actions field is used as a temporary parking place
- -- for these actions. The final tree is always rewritten to eliminate
- -- the need for this field, so in the tree passed to Gigi, this field
- -- is always set to No_List.
+ -- True. The Then_Actions field is used as a temporary parking place for
+ -- these actions. The final tree is always rewritten to eliminate the
+ -- need for this field, so in the tree passed to Gigi, this field is
+ -- always set to No_List.
-- Treat_Fixed_As_Integer (Flag14-Sem)
- -- This flag appears in operator nodes for divide, multiply, mod and
- -- rem on fixed-point operands. It indicates that the operands are
- -- to be treated as integer values, ignoring small values. This flag
- -- is only set as a result of expansion of fixed-point operations.
- -- Typically a fixed-point multplication in the source generates
- -- subsidiary multiplication and division operations that work with
- -- the underlying integer values and have this flag set. Note that
- -- this flag is not needed on other arithmetic operations (add, neg,
- -- subtract etc) since in these cases it is always the case that fixed
- -- is treated as integer. The Etype field MUST be set if this flag
- -- is set. The analyzer knows to leave such nodes alone, and whoever
- -- makes them must set the correct Etype value.
+ -- This flag appears in operator nodes for divide, multiply, mod and rem
+ -- on fixed-point operands. It indicates that the operands are to be
+ -- treated as integer values, ignoring small values. This flag is only
+ -- set as a result of expansion of fixed-point operations. Typically a
+ -- fixed-point multplication in the source generates subsidiary
+ -- multiplication and division operations that work with the underlying
+ -- integer values and have this flag set. Note that this flag is not
+ -- needed on other arithmetic operations (add, neg, subtract etc) since
+ -- in these cases it is always the case that fixed is treated as integer.
+ -- The Etype field MUST be set if this flag is set. The analyzer knows to
+ -- leave such nodes alone, and whoever makes them must set the correct
+ -- Etype value.
-- TSS_Elist (Elist3-Sem)
-- Present in N_Freeze_Entity nodes. Holds an element list containing
-- entries for each TSS (type support subprogram) associated with the
-- frozen type. The elements of the list are the entities for the
- -- subprograms (see package Exp_TSS for further details). Set to
- -- No_Elist if there are no type support subprograms for the type
- -- or if the freeze node is not for a type.
+ -- subprograms (see package Exp_TSS for further details). Set to No_Elist
+ -- if there are no type support subprograms for the type or if the freeze
+ -- node is not for a type.
-- Unreferenced_In_Spec (Flag7-Sem)
-- Present in N_With_Clause nodes. Set if the with clause is on the
-- package or subprogram spec where the main unit is the corresponding
- -- body, and is not referenced by the spec (it may still be referenced
- -- by the body, so this flag is used to generate the proper message
- -- (see Sem_Util.Check_Unused_Withs for details)
+ -- body, and is not referenced by the spec (it may still be referenced by
+ -- the body, so this flag is used to generate the proper message (see
+ -- Sem_Util.Check_Unused_Withs for details)
-- Was_Originally_Stub (Flag13-Sem)
- -- This flag is set in the node for a proper body that replaces a
- -- stub. During the analysis procedure, stubs in some situations
- -- get rewritten by the corresponding bodies, and we set this flag
- -- to remember that this happened. Note that it is not good enough
- -- to rely on the use of Original_Node here because of the case of
- -- nested instantiations where the substituted node can be copied.
+ -- This flag is set in the node for a proper body that replaces stub.
+ -- During the analysis procedure, stubs in some situations get rewritten
+ -- by the corresponding bodies, and we set this flag to remember that
+ -- this happened. Note that it is not good enough to rely on the use of
+ -- Original_Node here because of the case of nested instantiations where
+ -- the substituted node can be copied.
-- Zero_Cost_Handling (Flag5-Sem)
-- This flag is set in all handled sequence of statement and exception
-- handler nodes if eceptions are to be handled using the zero-cost
-- mechanism (see Ada.Exceptions and System.Exceptions in files
- -- a-except.ads/adb and s-except.ads for full details). What gigi
- -- needs to do for such a handler is simply to put the code in the
- -- handler somewhere. The front end has generated all necessary labels.
+ -- a-except.ads/adb and s-except.ads for full details). What gigi needs
+ -- to do for such a handler is simply to put the code in the handler
+ -- somewhere. The front end has generated all necessary labels.
--------------------------------------------------
-- Note on Use of End_Label and End_Span Fields --
-- Record Definition end record;
-- Enumeration Definition );
- -- The End_Label and End_Span fields are used to mark the locations
- -- of these lines, and also keep track of the label in the case where
- -- a label is present.
-
- -- For the first group above, the End_Label field of the corresponding
- -- node is used to point to the label identifier. In the case where
- -- there is no label in the source, the parser supplies a dummy
- -- identifier (with Comes_From_Source set to False), and the Sloc
- -- of this dummy identifier marks the location of the token following
- -- the END token.
-
- -- For the second group, the use of End_Label is similar, but the
- -- End_Label is found in the N_Handled_Sequence_Of_Statements node.
- -- This is done simply because in some cases there is no room in
- -- the parent node.
-
- -- For the third group, there is never any label, and instead of
- -- using End_Label, we use the End_Span field which gives the
- -- location of the token following END, relative to the starting
- -- Sloc of the construct, i.e. add Sloc (Node) + End_Span (Node)
- -- to get the Sloc of the IF or CASE following the End_Label.
-
- -- The record definition case is handled specially, we treat it
- -- as though it required an optional label which is never present,
- -- and so the parser always builds a dummy identifier with Comes
- -- From Source set False. The reason we do this, rather than using
- -- End_Span in this case, is that we want to generate a cross-ref
- -- entry for the end of a record, since it represents a scope for
- -- name declaration purposes.
-
- -- The enumeration definition case is handled in an exactly similar
- -- manner, building a dummy identifier to get a cross-reference.
-
- -- Note: the reason we store the difference as a Uint, instead of
- -- storing the Source_Ptr value directly, is that Source_Ptr values
- -- cannot be distinguished from other types of values, and we count
- -- on all general use fields being self describing. To make things
- -- easier for clients, note that we provide function End_Location,
- -- and procedure Set_End_Location to allow access to the logical
- -- value (which is the Source_Ptr value for the end token).
+ -- The End_Label and End_Span fields are used to mark the locations of
+ -- these lines, and also keep track of the label in the case where a label
+ -- is present.
+
+ -- For the first group above, the End_Label field of the corresponding node
+ -- is used to point to the label identifier. In the case where there is no
+ -- label in the source, the parser supplies a dummy identifier (with
+ -- Comes_From_Source set to False), and the Sloc of this dummy identifier
+ -- marks the location of the token following the END token.
+
+ -- For the second group, the use of End_Label is similar, but the End_Label
+ -- is found in the N_Handled_Sequence_Of_Statements node. This is done
+ -- simply because in some cases there is no room in the parent node.
+
+ -- For the third group, there is never any label, and instead of using
+ -- End_Label, we use the End_Span field which gives the location of the
+ -- token following END, relative to the starting Sloc of the construct,
+ -- i.e. add Sloc (Node) + End_Span (Node) to get the Sloc of the IF or CASE
+ -- following the End_Label.
+
+ -- The record definition case is handled specially, we treat it as though
+ -- it required an optional label which is never present, and so the parser
+ -- always builds a dummy identifier with Comes From Source set False. The
+ -- reason we do this, rather than using End_Span in this case, is that we
+ -- want to generate a cross-ref entry for the end of a record, since it
+ -- represents a scope for name declaration purposes.
+
+ -- The enumeration definition case is handled in an exactly similar manner,
+ -- building a dummy identifier to get a cross-reference.
+
+ -- Note: the reason we store the difference as a Uint, instead of storing
+ -- the Source_Ptr value directly, is that Source_Ptr values cannot be
+ -- distinguished from other types of values, and we count on all general
+ -- use fields being self describing. To make things easier for clients,
+ -- note that we provide function End_Location, and procedure
+ -- Set_End_Location to allow access to the logical value (which is the
+ -- Source_Ptr value for the end token).
---------------------
-- Syntactic Nodes --
-- An IDENTIFIER shall not be a reserved word
- -- In the Ada grammar identifiers are the bottom level tokens which
- -- have very few semantics. Actual program identifiers are direct
- -- names. If we were being 100% honest with the grammar, then we would
- -- have a node called N_Direct_Name which would point to an identifier.
- -- However, that's too many extra nodes, so we just use the N_Identifier
- -- node directly as a direct name, and it contains the expression fields
- -- and Entity field that correspond to its use as a direct name. In
- -- those few cases where identifiers appear in contexts where they are
- -- not direct names (pragmas, pragma argument associations, attribute
+ -- In the Ada grammar identifiers are the bottom level tokens which have
+ -- very few semantics. Actual program identifiers are direct names. If
+ -- we were being 100% honest with the grammar, then we would have a node
+ -- called N_Direct_Name which would point to an identifier. However,
+ -- that's too many extra nodes, so we just use the N_Identifier node
+ -- directly as a direct name, and it contains the expression fields and
+ -- Entity field that correspond to its use as a direct name. In those
+ -- few cases where identifiers appear in contexts where they are not
+ -- direct names (pragmas, pragma argument associations, attribute
-- references and attribute definition clauses), the Chars field of the
-- node contains the Name_Id for the identifier name.
- -- Note: in GNAT, a reserved word can be treated as an identifier
- -- in two cases. First, an incorrect use of a reserved word as an
- -- identifier is diagnosed and then treated as a normal identifier.
- -- Second, an attribute designator of the form of a reserved word
- -- (access, delta, digits, range) is treated as an identifier.
+ -- Note: in GNAT, a reserved word can be treated as an identifier in two
+ -- cases. First, an incorrect use of a reserved word as an identifier is
+ -- diagnosed and then treated as a normal identifier. Second, an
+ -- attribute designator of the form of a reserved word (access, delta,
+ -- digits, range) is treated as an identifier.
-- Note: The set of letters that is permitted in an identifier depends
-- on the character set in use. See package Csets for full details.
-- Has_Private_View (Flag11-Sem) set in generic units.
-- plus fields for expression
- -- Note: the Entity field will be missing (and set to Empty) for
- -- character literals whose type is Standard.Wide_Character or
- -- Standard.Character or a type derived from one of these two.
- -- In this case the character literal stands for its own coding.
- -- The reason we take this irregular short cut is to avoid the
- -- need to build lots of junk defining character literal nodes.
+ -- Note: the Entity field will be missing (set to Empty) for character
+ -- literals whose type is Standard.Wide_Character or Standard.Character
+ -- or a type derived from one of these two. In this case the character
+ -- literal stands for its own coding. The reason we take this irregular
+ -- short cut is to avoid the need to build lots of junk defining
+ -- character literal nodes.
-------------------------
-- 2.6 String Literal --
--------------------------------------------
-- FORMAL_DERIVED_TYPE_DEFINITION ::=
- -- [abstract] new SUBTYPE_MARK [[and INTERFACE_LIST] with private]
+ -- [abstract] [limited]
+ -- new SUBTYPE_MARK [[and INTERFACE_LIST] with private]
-- Note: this construct is not allowed in Ada 83 mode
-- N_Formal_Derived_Type_Definition
-- Subtype_Mark (Node4)
-- Private_Present (Flag15)
-- Abstract_Present (Flag4)
+ -- Limited_Present (Flag17)
-- Interface_List (List2) (set to No_List if none)
---------------------------------------------
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