1480 lines
65 KiB
Ada
1480 lines
65 KiB
Ada
------------------------------------------------------------------------------
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-- --
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-- GNAT COMPILER COMPONENTS --
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-- --
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-- P A R --
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-- --
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-- B o d y --
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-- --
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-- Copyright (C) 1992-2009, Free Software Foundation, Inc. --
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-- --
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-- GNAT is free software; you can redistribute it and/or modify it under --
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-- terms of the GNU General Public License as published by the Free Soft- --
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-- ware Foundation; either version 3, or (at your option) any later ver- --
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-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
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-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
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-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
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-- for more details. You should have received a copy of the GNU General --
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-- Public License distributed with GNAT; see file COPYING3. If not, go to --
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-- http://www.gnu.org/licenses for a complete copy of the license. --
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-- --
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-- GNAT was originally developed by the GNAT team at New York University. --
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-- Extensive contributions were provided by Ada Core Technologies Inc. --
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-- --
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------------------------------------------------------------------------------
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with Atree; use Atree;
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with Casing; use Casing;
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with Debug; use Debug;
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with Elists; use Elists;
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with Errout; use Errout;
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with Fname; use Fname;
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with Lib; use Lib;
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with Namet; use Namet;
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with Nlists; use Nlists;
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with Nmake; use Nmake;
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with Opt; use Opt;
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with Output; use Output;
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with Par_SCO; use Par_SCO;
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with Scans; use Scans;
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with Scn; use Scn;
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with Sinput; use Sinput;
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with Sinput.L; use Sinput.L;
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with Sinfo; use Sinfo;
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with Snames; use Snames;
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with Style;
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with Stylesw; use Stylesw;
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with Table;
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with Tbuild; use Tbuild;
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---------
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-- Par --
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---------
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function Par (Configuration_Pragmas : Boolean) return List_Id is
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Num_Library_Units : Natural := 0;
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-- Count number of units parsed (relevant only in syntax check only mode,
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-- since in semantics check mode only a single unit is permitted anyway)
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Save_Config_Switches : Config_Switches_Type;
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-- Variable used to save values of config switches while we parse the
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-- new unit, to be restored on exit for proper recursive behavior.
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Loop_Block_Count : Nat := 0;
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-- Counter used for constructing loop/block names (see the routine
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-- Par.Ch5.Get_Loop_Block_Name)
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--------------------
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-- Error Recovery --
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--------------------
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-- When an error is encountered, a call is made to one of the Error_Msg
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-- routines to record the error. If the syntax scan is not derailed by the
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-- error (e.g. a complaint that logical operators are inconsistent in an
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-- EXPRESSION), then control returns from the Error_Msg call, and the
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-- parse continues unimpeded.
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-- If on the other hand, the Error_Msg represents a situation from which
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-- the parser cannot recover locally, the exception Error_Resync is raised
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-- immediately after the call to Error_Msg. Handlers for Error_Resync
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-- are located at strategic points to resynchronize the parse. For example,
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-- when an error occurs in a statement, the handler skips to the next
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-- semicolon and continues the scan from there.
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-- Each parsing procedure contains a note with the heading "Error recovery"
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-- which shows if it can propagate the Error_Resync exception. In order
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-- not to propagate the exception, a procedure must either contain its own
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-- handler for this exception, or it must not call any other routines which
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-- propagate the exception.
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-- Note: the arrangement of Error_Resync handlers is such that it should
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-- never be possible to transfer control through a procedure which made
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-- an entry in the scope stack, invalidating the contents of the stack.
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Error_Resync : exception;
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-- Exception raised on error that is not handled locally, see above
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Last_Resync_Point : Source_Ptr;
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-- The resynchronization routines in Par.Sync run a risk of getting
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-- stuck in an infinite loop if they do not skip a token, and the caller
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-- keeps repeating the same resync call. On the other hand, if they skip
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-- a token unconditionally, some recovery opportunities are missed. The
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-- variable Last_Resync_Point records the token location previously set
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-- by a Resync call, and if a subsequent Resync call occurs at the same
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-- location, then the Resync routine does guarantee to skip a token.
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--------------------------------------------
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-- Handling Semicolon Used in Place of IS --
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--------------------------------------------
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-- The following global variables are used in handling the error situation
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-- of using a semicolon in place of IS in a subprogram declaration as in:
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-- procedure X (Y : Integer);
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-- Q : Integer;
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-- begin
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-- ...
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-- end;
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-- The two contexts in which this can appear are at the outer level, and
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-- within a declarative region. At the outer level, we know something is
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-- wrong as soon as we see the Q (or begin, if there are no declarations),
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-- and we can immediately decide that the semicolon should have been IS.
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-- The situation in a declarative region is more complex. The declaration
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-- of Q could belong to the outer region, and we do not know that we have
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-- an error until we hit the begin. It is still not clear at this point
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-- from a syntactic point of view that something is wrong, because the
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-- begin could belong to the enclosing subprogram or package. However, we
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-- can incorporate a bit of semantic knowledge and note that the body of
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-- X is missing, so we definitely DO have an error. We diagnose this error
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-- as semicolon in place of IS on the subprogram line.
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-- There are two styles for this diagnostic. If the begin immediately
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-- follows the semicolon, then we can place a flag (IS expected) right
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-- on the semicolon. Otherwise we do not detect the error until we hit
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-- the begin which refers back to the line with the semicolon.
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-- To control the process in the second case, the following global
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-- variables are set to indicate that we have a subprogram declaration
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-- whose body is required and has not yet been found. The prefix SIS
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-- stands for "Subprogram IS" handling.
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SIS_Entry_Active : Boolean := False;
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-- Set True to indicate that an entry is active (i.e. that a subprogram
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-- declaration has been encountered, and no body for this subprogram has
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-- been encountered). The remaining fields are valid only if this is True.
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SIS_Labl : Node_Id;
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-- Subprogram designator
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SIS_Sloc : Source_Ptr;
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-- Source location of FUNCTION/PROCEDURE keyword
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SIS_Ecol : Column_Number;
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-- Column number of FUNCTION/PROCEDURE keyword
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SIS_Semicolon_Sloc : Source_Ptr;
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-- Source location of semicolon at end of subprogram declaration
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SIS_Declaration_Node : Node_Id;
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-- Pointer to tree node for subprogram declaration
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SIS_Missing_Semicolon_Message : Error_Msg_Id;
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-- Used to save message ID of missing semicolon message (which will be
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-- modified to missing IS if necessary). Set to No_Error_Msg in the
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-- normal (non-error) case.
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-- Five things can happen to an active SIS entry
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-- 1. If a BEGIN is encountered with an SIS entry active, then we have
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-- exactly the situation in which we know the body of the subprogram is
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-- missing. After posting an error message, we change the spec to a body,
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-- rechaining the declarations that intervened between the spec and BEGIN.
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-- 2. Another subprogram declaration or body is encountered. In this
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-- case the entry gets overwritten with the information for the new
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-- subprogram declaration. We don't catch some nested cases this way,
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-- but it doesn't seem worth the effort.
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-- 3. A nested declarative region (e.g. package declaration or package
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-- body) is encountered. The SIS active indication is reset at the start
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-- of such a nested region. Again, like case 2, this causes us to miss
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-- some nested cases, but it doesn't seen worth the effort to stack and
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-- unstack the SIS information. Maybe we will reconsider this if we ever
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-- get a complaint about a missed case.
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-- 4. We encounter a valid pragma INTERFACE or IMPORT that effectively
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-- supplies the missing body. In this case we reset the entry.
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-- 5. We encounter the end of the declarative region without encountering
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-- a BEGIN first. In this situation we simply reset the entry. We know
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-- that there is a missing body, but it seems more reasonable to let the
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-- later semantic checking discover this.
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----------------------------------------------------
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-- Handling of Reserved Words Used as Identifiers --
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----------------------------------------------------
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-- Note: throughout the parser, the terms reserved word and keyword are
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-- used interchangeably to refer to the same set of reserved keywords
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-- (including until, protected, etc).
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-- If a reserved word is used in place of an identifier, the parser where
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-- possible tries to recover gracefully. In particular, if the keyword is
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-- clearly spelled using identifier casing, e.g. Until in a source program
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-- using mixed case identifiers and lower case keywords, then the keyword
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-- is treated as an identifier if it appears in a place where an identifier
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-- is required.
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-- The situation is more complex if the keyword is spelled with normal
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-- keyword casing. In this case, the parser is more reluctant to consider
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-- it to be intended as an identifier, unless it has some further
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-- confirmation.
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-- In the case of an identifier appearing in the identifier list of a
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-- declaration, the appearance of a comma or colon right after the keyword
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-- on the same line is taken as confirmation. For an enumeration literal,
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-- a comma or right paren right after the identifier is also treated as
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-- adequate confirmation.
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-- The following type is used in calls to Is_Reserved_Identifier and
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-- also to P_Defining_Identifier and P_Identifier. The default for all
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-- these functions is that reserved words in reserved word case are not
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-- considered to be reserved identifiers. The Id_Check value indicates
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-- tokens, which if they appear immediately after the identifier, are
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-- taken as confirming that the use of an identifier was expected
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type Id_Check is
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(None,
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-- Default, no special token test
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C_Comma_Right_Paren,
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-- Consider as identifier if followed by comma or right paren
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C_Comma_Colon,
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-- Consider as identifier if followed by comma or colon
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C_Do,
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-- Consider as identifier if followed by DO
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C_Dot,
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-- Consider as identifier if followed by period
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C_Greater_Greater,
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-- Consider as identifier if followed by >>
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C_In,
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-- Consider as identifier if followed by IN
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C_Is,
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-- Consider as identifier if followed by IS
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C_Left_Paren_Semicolon,
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-- Consider as identifier if followed by left paren or semicolon
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C_Use,
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-- Consider as identifier if followed by USE
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C_Vertical_Bar_Arrow);
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-- Consider as identifier if followed by | or =>
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--------------------------------------------
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-- Handling IS Used in Place of Semicolon --
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--------------------------------------------
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-- This is a somewhat trickier situation, and we can't catch it in all
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-- cases, but we do our best to detect common situations resulting from
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-- a "cut and paste" operation which forgets to change the IS to semicolon.
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-- Consider the following example:
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-- package body X is
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-- procedure A;
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-- procedure B is
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-- procedure C;
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-- ...
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-- procedure D is
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-- begin
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-- ...
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-- end;
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-- begin
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-- ...
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-- end;
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-- The trouble is that the section of text from PROCEDURE B through END;
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-- constitutes a valid procedure body, and the danger is that we find out
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-- far too late that something is wrong (indeed most compilers will behave
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-- uncomfortably on the above example).
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-- We have two approaches to helping to control this situation. First we
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-- make every attempt to avoid swallowing the last END; if we can be sure
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-- that some error will result from doing so. In particular, we won't
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-- accept the END; unless it is exactly correct (in particular it must not
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-- have incorrect name tokens), and we won't accept it if it is immediately
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-- followed by end of file, WITH or SEPARATE (all tokens that unmistakeably
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-- signal the start of a compilation unit, and which therefore allow us to
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-- reserve the END; for the outer level.) For more details on this aspect
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-- of the handling, see package Par.Endh.
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-- If we can avoid eating up the END; then the result in the absence of
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-- any additional steps would be to post a missing END referring back to
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-- the subprogram with the bogus IS. Similarly, if the enclosing package
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-- has no BEGIN, then the result is a missing BEGIN message, which again
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-- refers back to the subprogram header.
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-- Such an error message is not too bad (it's already a big improvement
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-- over what many parsers do), but it's not ideal, because the declarations
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-- following the IS have been absorbed into the wrong scope. In the above
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-- case, this could result for example in a bogus complaint that the body
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-- of D was missing from the package.
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-- To catch at least some of these cases, we take the following additional
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-- steps. First, a subprogram body is marked as having a suspicious IS if
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-- the declaration line is followed by a line which starts with a symbol
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-- that can start a declaration in the same column, or to the left of the
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-- column in which the FUNCTION or PROCEDURE starts (normal style is to
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-- indent any declarations which really belong a subprogram). If such a
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-- subprogram encounters a missing BEGIN or missing END, then we decide
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-- that the IS should have been a semicolon, and the subprogram body node
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-- is marked (by setting the Bad_Is_Detected flag true. Note that we do
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-- not do this for library level procedures, only for nested procedures,
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-- since for library level procedures, we must have a body.
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-- The processing for a declarative part checks to see if the last
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-- declaration scanned is marked in this way, and if it is, the tree
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-- is modified to reflect the IS being interpreted as a semicolon.
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---------------------------------------------------
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-- Parser Type Definitions and Control Variables --
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---------------------------------------------------
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-- The following variable and associated type declaration are used by the
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-- expression parsing routines to return more detailed information about
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-- the categorization of a parsed expression.
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type Expr_Form_Type is (
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EF_Simple_Name, -- Simple name, i.e. possibly qualified identifier
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EF_Name, -- Simple expression which could also be a name
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EF_Simple, -- Simple expression which is not call or name
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EF_Range_Attr, -- Range attribute reference
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EF_Non_Simple); -- Expression that is not a simple expression
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Expr_Form : Expr_Form_Type;
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-- The following type is used for calls to P_Subprogram, P_Package, P_Task,
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-- P_Protected to indicate which of several possibilities is acceptable.
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type Pf_Rec is record
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Spcn : Boolean; -- True if specification OK
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Decl : Boolean; -- True if declaration OK
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Gins : Boolean; -- True if generic instantiation OK
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Pbod : Boolean; -- True if proper body OK
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Rnam : Boolean; -- True if renaming declaration OK
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Stub : Boolean; -- True if body stub OK
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Fil1 : Boolean; -- Filler to fill to 8 bits
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Fil2 : Boolean; -- Filler to fill to 8 bits
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end record;
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pragma Pack (Pf_Rec);
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function T return Boolean renames True;
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function F return Boolean renames False;
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Pf_Decl_Gins_Pbod_Rnam_Stub : constant Pf_Rec :=
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Pf_Rec'(F, T, T, T, T, T, F, F);
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Pf_Decl : constant Pf_Rec :=
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Pf_Rec'(F, T, F, F, F, F, F, F);
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Pf_Decl_Gins_Pbod_Rnam : constant Pf_Rec :=
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Pf_Rec'(F, T, T, T, T, F, F, F);
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Pf_Decl_Pbod : constant Pf_Rec :=
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Pf_Rec'(F, T, F, T, F, F, F, F);
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Pf_Pbod : constant Pf_Rec :=
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Pf_Rec'(F, F, F, T, F, F, F, F);
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Pf_Spcn : constant Pf_Rec :=
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Pf_Rec'(T, F, F, F, F, F, F, F);
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-- The above are the only allowed values of Pf_Rec arguments
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type SS_Rec is record
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Eftm : Boolean; -- ELSIF can terminate sequence
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Eltm : Boolean; -- ELSE can terminate sequence
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Extm : Boolean; -- EXCEPTION can terminate sequence
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Ortm : Boolean; -- OR can terminate sequence
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Sreq : Boolean; -- at least one statement required
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Tatm : Boolean; -- THEN ABORT can terminate sequence
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Whtm : Boolean; -- WHEN can terminate sequence
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Unco : Boolean; -- Unconditional terminate after one statement
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end record;
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pragma Pack (SS_Rec);
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SS_Eftm_Eltm_Sreq : constant SS_Rec := SS_Rec'(T, T, F, F, T, F, F, F);
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SS_Eltm_Ortm_Tatm : constant SS_Rec := SS_Rec'(F, T, F, T, F, T, F, F);
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SS_Extm_Sreq : constant SS_Rec := SS_Rec'(F, F, T, F, T, F, F, F);
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SS_None : constant SS_Rec := SS_Rec'(F, F, F, F, F, F, F, F);
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SS_Ortm_Sreq : constant SS_Rec := SS_Rec'(F, F, F, T, T, F, F, F);
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SS_Sreq : constant SS_Rec := SS_Rec'(F, F, F, F, T, F, F, F);
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SS_Sreq_Whtm : constant SS_Rec := SS_Rec'(F, F, F, F, T, F, T, F);
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SS_Whtm : constant SS_Rec := SS_Rec'(F, F, F, F, F, F, T, F);
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SS_Unco : constant SS_Rec := SS_Rec'(F, F, F, F, F, F, F, T);
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Goto_List : Elist_Id;
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-- List of goto nodes appearing in the current compilation. Used to
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-- recognize natural loops and convert them into bona fide loops for
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-- optimization purposes.
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Label_List : Elist_Id;
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-- List of label nodes for labels appearing in the current compilation.
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-- Used by Par.Labl to construct the corresponding implicit declarations.
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-----------------
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-- Scope Table --
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-----------------
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-- The scope table, also referred to as the scope stack, is used to record
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-- the current scope context. It is organized as a stack, with inner nested
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-- entries corresponding to higher entries on the stack. An entry is made
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-- when the parser encounters the opening of a nested construct (such as a
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-- record, task, package etc.), and then package Par.Endh uses this stack
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-- to deal with END lines (including properly dealing with END nesting
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-- errors).
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type SS_End_Type is
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-- Type of end entry required for this scope. The last two entries are
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-- used only in the subprogram body case to mark the case of a suspicious
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-- IS, or a bad IS (i.e. suspicions confirmed by missing BEGIN or END).
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-- See separate section on dealing with IS used in place of semicolon.
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-- Note that for many purposes E_Name, E_Suspicious_Is and E_Bad_Is are
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-- treated the same (E_Suspicious_Is and E_Bad_Is are simply special cases
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-- of E_Name). They are placed at the end of the enumeration so that a
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-- test for >= E_Name catches all three cases efficiently.
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(E_Dummy, -- dummy entry at outer level
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E_Case, -- END CASE;
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E_If, -- END IF;
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E_Loop, -- END LOOP;
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E_Record, -- END RECORD;
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E_Return, -- END RETURN;
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E_Select, -- END SELECT;
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E_Name, -- END [name];
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E_Suspicious_Is, -- END [name]; (case of suspicious IS)
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E_Bad_Is); -- END [name]; (case of bad IS)
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-- The following describes a single entry in the scope table
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type Scope_Table_Entry is record
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Etyp : SS_End_Type;
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-- Type of end entry, as per above description
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Lreq : Boolean;
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-- A flag indicating whether the label, if present, is required to
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-- appear on the end line. It is referenced only in the case of Etyp is
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-- equal to E_Name or E_Suspicious_Is where the name may or may not be
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-- required (yes for labeled block, no in other cases). Note that for
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-- all cases except begin, the question of whether a label is required
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-- can be determined from the other fields (for loop, it is required if
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-- it is present, and for the other constructs it is never required or
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-- allowed).
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Ecol : Column_Number;
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-- Contains the absolute column number (with tabs expanded) of the
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-- expected column of the end assuming normal Ada indentation usage. If
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-- the RM_Column_Check mode is set, this value is used for generating
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-- error messages about indentation. Otherwise it is used only to
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|
-- control heuristic error recovery actions.
|
|
|
|
Labl : Node_Id;
|
|
-- This field is used only for the LOOP and BEGIN cases, and is the
|
|
-- Node_Id value of the label name. For all cases except child units,
|
|
-- this value is an entity whose Chars field contains the name pointer
|
|
-- that identifies the label uniquely. For the child unit case the Labl
|
|
-- field references an N_Defining_Program_Unit_Name node for the name.
|
|
-- For cases other than LOOP or BEGIN, the Label field is set to Error,
|
|
-- indicating that it is an error to have a label on the end line.
|
|
-- (this is really a misuse of Error since there is no Error ???)
|
|
|
|
Decl : List_Id;
|
|
-- Points to the list of declarations (i.e. the declarative part)
|
|
-- associated with this construct. It is set only in the END [name]
|
|
-- cases, and is set to No_List for all other cases which do not have a
|
|
-- declarative unit associated with them. This is used for determining
|
|
-- the proper location for implicit label declarations.
|
|
|
|
Node : Node_Id;
|
|
-- Empty except in the case of entries for IF and CASE statements, in
|
|
-- which case it contains the N_If_Statement or N_Case_Statement node.
|
|
-- This is used for setting the End_Span field.
|
|
|
|
Sloc : Source_Ptr;
|
|
-- Source location of the opening token of the construct. This is used
|
|
-- to refer back to this line in error messages (such as missing or
|
|
-- incorrect end lines). The Sloc field is not used, and is not set, if
|
|
-- a label is present (the Labl field provides the text name of the
|
|
-- label in this case, which is fine for error messages).
|
|
|
|
S_Is : Source_Ptr;
|
|
-- S_Is is relevant only if Etyp is set to E_Suspicious_Is or E_Bad_Is.
|
|
-- It records the location of the IS that is considered to be
|
|
-- suspicious.
|
|
|
|
Junk : Boolean;
|
|
-- A boolean flag that is set true if the opening entry is the dubious
|
|
-- result of some prior error, e.g. a record entry where the record
|
|
-- keyword was missing. It is used to suppress the issuing of a
|
|
-- corresponding junk complaint about the end line (we do not want
|
|
-- to complain about a missing end record when there was no record).
|
|
end record;
|
|
|
|
-- The following declares the scope table itself. The Last field is the
|
|
-- stack pointer, so that Scope.Table (Scope.Last) is the top entry. The
|
|
-- oldest entry, at Scope_Stack (0), is a dummy entry with Etyp set to
|
|
-- E_Dummy, and the other fields undefined. This dummy entry ensures that
|
|
-- Scope_Stack (Scope_Stack_Ptr).Etyp can always be tested, and that the
|
|
-- scope stack pointer is always in range.
|
|
|
|
package Scope is new Table.Table (
|
|
Table_Component_Type => Scope_Table_Entry,
|
|
Table_Index_Type => Int,
|
|
Table_Low_Bound => 0,
|
|
Table_Initial => 50,
|
|
Table_Increment => 100,
|
|
Table_Name => "Scope");
|
|
|
|
---------------------------------
|
|
-- Parsing Routines by Chapter --
|
|
---------------------------------
|
|
|
|
-- Uncommented declarations in this section simply parse the construct
|
|
-- corresponding to their name, and return an ID value for the Node or
|
|
-- List that is created.
|
|
|
|
-------------
|
|
-- Par.Ch2 --
|
|
-------------
|
|
|
|
package Ch2 is
|
|
function P_Pragma (Skipping : Boolean := False) return Node_Id;
|
|
-- Scan out a pragma. If Skipping is True, then the caller is skipping
|
|
-- the pragma in the context of illegal placement (this is used to avoid
|
|
-- some junk cascaded messages).
|
|
|
|
function P_Identifier (C : Id_Check := None) return Node_Id;
|
|
-- Scans out an identifier. The parameter C determines the treatment
|
|
-- of reserved identifiers. See declaration of Id_Check for details.
|
|
|
|
function P_Pragmas_Opt return List_Id;
|
|
-- This function scans for a sequence of pragmas in other than a
|
|
-- declaration sequence or statement sequence context. All pragmas
|
|
-- can appear except pragmas Assert and Debug, which are only allowed
|
|
-- in a declaration or statement sequence context.
|
|
|
|
procedure P_Pragmas_Misplaced;
|
|
-- Skips misplaced pragmas with a complaint
|
|
|
|
procedure P_Pragmas_Opt (List : List_Id);
|
|
-- Parses optional pragmas and appends them to the List
|
|
end Ch2;
|
|
|
|
-------------
|
|
-- Par.Ch3 --
|
|
-------------
|
|
|
|
package Ch3 is
|
|
Missing_Begin_Msg : Error_Msg_Id;
|
|
-- This variable is set by a call to P_Declarative_Part. Normally it
|
|
-- is set to No_Error_Msg, indicating that no special processing is
|
|
-- required by the caller. The special case arises when a statement
|
|
-- is found in the sequence of declarations. In this case the Id of
|
|
-- the message issued ("declaration expected") is preserved in this
|
|
-- variable, then the caller can change it to an appropriate missing
|
|
-- begin message if indeed the BEGIN is missing.
|
|
|
|
function P_Array_Type_Definition return Node_Id;
|
|
function P_Basic_Declarative_Items return List_Id;
|
|
function P_Constraint_Opt return Node_Id;
|
|
function P_Declarative_Part return List_Id;
|
|
function P_Discrete_Choice_List return List_Id;
|
|
function P_Discrete_Range return Node_Id;
|
|
function P_Discrete_Subtype_Definition return Node_Id;
|
|
function P_Known_Discriminant_Part_Opt return List_Id;
|
|
function P_Signed_Integer_Type_Definition return Node_Id;
|
|
function P_Range return Node_Id;
|
|
function P_Range_Constraint return Node_Id;
|
|
function P_Record_Definition return Node_Id;
|
|
function P_Subtype_Mark return Node_Id;
|
|
function P_Subtype_Mark_Resync return Node_Id;
|
|
function P_Unknown_Discriminant_Part_Opt return Boolean;
|
|
|
|
function P_Access_Definition
|
|
(Null_Exclusion_Present : Boolean) return Node_Id;
|
|
-- Ada 2005 (AI-231/AI-254): The caller parses the null-exclusion part
|
|
-- and indicates if it was present
|
|
|
|
function P_Access_Type_Definition
|
|
(Header_Already_Parsed : Boolean := False) return Node_Id;
|
|
-- Ada 2005 (AI-254): The formal is used to indicate if the caller has
|
|
-- parsed the null_exclusion part. In this case the caller has also
|
|
-- removed the ACCESS token
|
|
|
|
procedure P_Component_Items (Decls : List_Id);
|
|
-- Scan out one or more component items and append them to the given
|
|
-- list. Only scans out more than one declaration in the case where the
|
|
-- source has a single declaration with multiple defining identifiers.
|
|
|
|
function P_Defining_Identifier (C : Id_Check := None) return Node_Id;
|
|
-- Scan out a defining identifier. The parameter C controls the
|
|
-- treatment of errors in case a reserved word is scanned. See the
|
|
-- declaration of this type for details.
|
|
|
|
function P_Interface_Type_Definition
|
|
(Abstract_Present : Boolean) return Node_Id;
|
|
-- Ada 2005 (AI-251): Parse the interface type definition part. Abstract
|
|
-- Present indicates if the reserved word "abstract" has been previously
|
|
-- found. It is used to report an error message because interface types
|
|
-- are by definition abstract tagged. We generate a record_definition
|
|
-- node if the list of interfaces is empty; otherwise we generate a
|
|
-- derived_type_definition node (the first interface in this list is the
|
|
-- ancestor interface).
|
|
|
|
function P_Null_Exclusion
|
|
(Allow_Anonymous_In_95 : Boolean := False) return Boolean;
|
|
-- Ada 2005 (AI-231): Parse the null-excluding part. A True result
|
|
-- indicates that the null-excluding part was present.
|
|
--
|
|
-- Allow_Anonymous_In_95 is True if we are in a context that allows
|
|
-- anonymous access types in Ada 95, in which case "not null" is legal
|
|
-- if it precedes "access".
|
|
|
|
function P_Subtype_Indication
|
|
(Not_Null_Present : Boolean := False) return Node_Id;
|
|
-- Ada 2005 (AI-231): The flag Not_Null_Present indicates that the
|
|
-- null-excluding part has been scanned out and it was present.
|
|
|
|
function P_Range_Or_Subtype_Mark
|
|
(Allow_Simple_Expression : Boolean := False) return Node_Id;
|
|
-- Scans out a range or subtype mark, and also permits a general simple
|
|
-- expression if Allow_Simple_Expresion is set to True.
|
|
|
|
function Init_Expr_Opt (P : Boolean := False) return Node_Id;
|
|
-- If an initialization expression is present (:= expression), then
|
|
-- it is scanned out and returned, otherwise Empty is returned if no
|
|
-- initialization expression is present. This procedure also handles
|
|
-- certain common error cases cleanly. The parameter P indicates if
|
|
-- a right paren can follow the expression (default = no right paren
|
|
-- allowed).
|
|
|
|
procedure Skip_Declaration (S : List_Id);
|
|
-- Used when scanning statements to skip past a misplaced declaration
|
|
-- The declaration is scanned out and appended to the given list.
|
|
-- Token is known to be a declaration token (in Token_Class_Declk)
|
|
-- on entry, so there definition is a declaration to be scanned.
|
|
|
|
function P_Subtype_Indication
|
|
(Subtype_Mark : Node_Id;
|
|
Not_Null_Present : Boolean := False) return Node_Id;
|
|
-- This version of P_Subtype_Indication is called when the caller has
|
|
-- already scanned out the subtype mark which is passed as a parameter.
|
|
-- Ada 2005 (AI-231): The flag Not_Null_Present indicates that the
|
|
-- null-excluding part has been scanned out and it was present.
|
|
|
|
function P_Subtype_Mark_Attribute (Type_Node : Node_Id) return Node_Id;
|
|
-- Parse a subtype mark attribute. The caller has already parsed the
|
|
-- subtype mark, which is passed in as the argument, and has checked
|
|
-- that the current token is apostrophe.
|
|
end Ch3;
|
|
|
|
-------------
|
|
-- Par.Ch4 --
|
|
-------------
|
|
|
|
package Ch4 is
|
|
function P_Aggregate return Node_Id;
|
|
function P_Expression return Node_Id;
|
|
function P_Expression_Or_Range_Attribute return Node_Id;
|
|
function P_Function_Name return Node_Id;
|
|
function P_Name return Node_Id;
|
|
function P_Qualified_Simple_Name return Node_Id;
|
|
function P_Qualified_Simple_Name_Resync return Node_Id;
|
|
function P_Simple_Expression return Node_Id;
|
|
function P_Simple_Expression_Or_Range_Attribute return Node_Id;
|
|
|
|
function P_Conditional_Expression return Node_Id;
|
|
-- Scans out a conditional expression. Called with token pointing to
|
|
-- the IF keyword, and returns pointing to the terminating right paren,
|
|
-- semicolon or comma, but does not consume this terminating token.
|
|
|
|
function P_Expression_If_OK return Node_Id;
|
|
-- Scans out an expression in a context where a conditional expression
|
|
-- is permitted to appear without surrounding parentheses.
|
|
|
|
function P_Expression_No_Right_Paren return Node_Id;
|
|
-- Scans out an expression in contexts where the expression cannot be
|
|
-- terminated by a right paren (gives better error recovery if an errant
|
|
-- right paren is found after the expression).
|
|
|
|
function P_Expression_Or_Range_Attribute_If_OK return Node_Id;
|
|
-- Scans out an expression or range attribute where a conditional
|
|
-- expression is permitted to appear without surrounding parentheses.
|
|
|
|
function P_Qualified_Expression (Subtype_Mark : Node_Id) return Node_Id;
|
|
-- This routine scans out a qualified expression when the caller has
|
|
-- already scanned out the name and apostrophe of the construct.
|
|
end Ch4;
|
|
|
|
-------------
|
|
-- Par.Ch5 --
|
|
-------------
|
|
|
|
package Ch5 is
|
|
function P_Statement_Name (Name_Node : Node_Id) return Node_Id;
|
|
-- Given a node representing a name (which is a call), converts it
|
|
-- to the syntactically corresponding procedure call statement.
|
|
|
|
function P_Sequence_Of_Statements (SS_Flags : SS_Rec) return List_Id;
|
|
-- The argument indicates the acceptable termination tokens.
|
|
-- See body in Par.Ch5 for details of the use of this parameter.
|
|
|
|
procedure Parse_Decls_Begin_End (Parent : Node_Id);
|
|
-- Parses declarations and handled statement sequence, setting
|
|
-- fields of Parent node appropriately.
|
|
end Ch5;
|
|
|
|
-------------
|
|
-- Par.Ch6 --
|
|
-------------
|
|
|
|
package Ch6 is
|
|
function P_Designator return Node_Id;
|
|
function P_Defining_Program_Unit_Name return Node_Id;
|
|
function P_Formal_Part return List_Id;
|
|
function P_Parameter_Profile return List_Id;
|
|
function P_Return_Statement return Node_Id;
|
|
function P_Subprogram_Specification return Node_Id;
|
|
|
|
procedure P_Mode (Node : Node_Id);
|
|
-- Sets In_Present and/or Out_Present flags in Node scanning past IN,
|
|
-- OUT or IN OUT tokens in the source.
|
|
|
|
function P_Subprogram (Pf_Flags : Pf_Rec) return Node_Id;
|
|
-- Scans out any construct starting with either of the keywords
|
|
-- PROCEDURE or FUNCTION. The parameter indicates which possible
|
|
-- possible kinds of construct (body, spec, instantiation etc.)
|
|
-- are permissible in the current context.
|
|
end Ch6;
|
|
|
|
-------------
|
|
-- Par.Ch7 --
|
|
-------------
|
|
|
|
package Ch7 is
|
|
function P_Package (Pf_Flags : Pf_Rec) return Node_Id;
|
|
-- Scans out any construct starting with the keyword PACKAGE. The
|
|
-- parameter indicates which possible kinds of construct (body, spec,
|
|
-- instantiation etc.) are permissible in the current context.
|
|
end Ch7;
|
|
|
|
-------------
|
|
-- Par.Ch8 --
|
|
-------------
|
|
|
|
package Ch8 is
|
|
function P_Use_Clause return Node_Id;
|
|
end Ch8;
|
|
|
|
-------------
|
|
-- Par.Ch9 --
|
|
-------------
|
|
|
|
package Ch9 is
|
|
function P_Abort_Statement return Node_Id;
|
|
function P_Abortable_Part return Node_Id;
|
|
function P_Accept_Statement return Node_Id;
|
|
function P_Delay_Statement return Node_Id;
|
|
function P_Entry_Body return Node_Id;
|
|
function P_Protected return Node_Id;
|
|
function P_Requeue_Statement return Node_Id;
|
|
function P_Select_Statement return Node_Id;
|
|
function P_Task return Node_Id;
|
|
function P_Terminate_Alternative return Node_Id;
|
|
end Ch9;
|
|
|
|
--------------
|
|
-- Par.Ch10 --
|
|
--------------
|
|
|
|
package Ch10 is
|
|
function P_Compilation_Unit return Node_Id;
|
|
-- Note: this function scans a single compilation unit, and checks that
|
|
-- an end of file follows this unit, diagnosing any unexpected input as
|
|
-- an error, and then skipping it, so that Token is set to Tok_EOF on
|
|
-- return. An exception is in syntax-only mode, where multiple
|
|
-- compilation units are permitted. In this case, P_Compilation_Unit
|
|
-- does not check for end of file and there may be more compilation
|
|
-- units to scan. The caller can uniquely detect this situation by the
|
|
-- fact that Token is not set to Tok_EOF on return.
|
|
--
|
|
-- What about multiple unit/file capability that now exists???
|
|
--
|
|
-- The Ignore parameter is normally set False. It is set True in the
|
|
-- multiple unit per file mode if we are skipping past a unit that we
|
|
-- are not interested in.
|
|
end Ch10;
|
|
|
|
--------------
|
|
-- Par.Ch11 --
|
|
--------------
|
|
|
|
package Ch11 is
|
|
function P_Handled_Sequence_Of_Statements return Node_Id;
|
|
function P_Raise_Statement return Node_Id;
|
|
|
|
function Parse_Exception_Handlers return List_Id;
|
|
-- Parses the partial construct EXCEPTION followed by a list of
|
|
-- exception handlers which appears in a number of productions, and
|
|
-- returns the list of exception handlers.
|
|
end Ch11;
|
|
|
|
--------------
|
|
-- Par.Ch12 --
|
|
--------------
|
|
|
|
package Ch12 is
|
|
function P_Generic return Node_Id;
|
|
function P_Generic_Actual_Part_Opt return List_Id;
|
|
end Ch12;
|
|
|
|
--------------
|
|
-- Par.Ch13 --
|
|
--------------
|
|
|
|
package Ch13 is
|
|
function P_Representation_Clause return Node_Id;
|
|
|
|
function P_Code_Statement (Subtype_Mark : Node_Id) return Node_Id;
|
|
-- Function to parse a code statement. The caller has scanned out
|
|
-- the name to be used as the subtype mark (but has not checked that
|
|
-- it is suitable for use as a subtype mark, i.e. is either an
|
|
-- identifier or a selected component). The current token is an
|
|
-- apostrophe and the following token is either a left paren or
|
|
-- RANGE (the latter being an error to be caught by P_Code_Statement.
|
|
end Ch13;
|
|
|
|
-- Note: the parsing for annexe J features (i.e. obsolescent features)
|
|
-- is found in the logical section where these features would be if
|
|
-- they were not obsolescent. In particular:
|
|
|
|
-- Delta constraint is parsed by P_Delta_Constraint (3.5.9)
|
|
-- At clause is parsed by P_At_Clause (13.1)
|
|
-- Mod clause is parsed by P_Mod_Clause (13.5.1)
|
|
|
|
--------------
|
|
-- Par.Endh --
|
|
--------------
|
|
|
|
-- Routines for handling end lines, including scope recovery
|
|
|
|
package Endh is
|
|
function Check_End return Boolean;
|
|
-- Called when an end sequence is required. In the absence of an error
|
|
-- situation, Token contains Tok_End on entry, but in a missing end
|
|
-- case, this may not be the case. Pop_End_Context is used to determine
|
|
-- the appropriate action to be taken. The returned result is True if
|
|
-- an End sequence was encountered and False if no End sequence was
|
|
-- present. This occurs if the END keyword encountered was determined
|
|
-- to be improper and deleted (i.e. Pop_End_Context set End_Action to
|
|
-- Skip_And_Reject). Note that the END sequence includes a semicolon,
|
|
-- except in the case of END RECORD, where a semicolon follows the END
|
|
-- RECORD, but is not part of the record type definition itself.
|
|
|
|
procedure End_Skip;
|
|
-- Skip past an end sequence. On entry Token contains Tok_End, and we
|
|
-- we know that the end sequence is syntactically incorrect, and that
|
|
-- an appropriate error message has already been posted. The mission
|
|
-- is simply to position the scan pointer to be the best guess of the
|
|
-- position after the end sequence. We do not issue any additional
|
|
-- error messages while carrying this out.
|
|
|
|
procedure End_Statements (Parent : Node_Id := Empty);
|
|
-- Called when an end is required or expected to terminate a sequence
|
|
-- of statements. The caller has already made an appropriate entry in
|
|
-- the Scope.Table to describe the expected form of the end. This can
|
|
-- only be used in cases where the only appropriate terminator is end.
|
|
-- If Parent is non-empty, then if a correct END line is encountered,
|
|
-- the End_Label field of Parent is set appropriately.
|
|
end Endh;
|
|
|
|
--------------
|
|
-- Par.Sync --
|
|
--------------
|
|
|
|
-- These procedures are used to resynchronize after errors. Following an
|
|
-- error which is not immediately locally recoverable, the exception
|
|
-- Error_Resync is raised. The handler for Error_Resync typically calls
|
|
-- one of these recovery procedures to resynchronize the source position
|
|
-- to a point from which parsing can be restarted.
|
|
|
|
-- Note: these procedures output an information message that tokens are
|
|
-- being skipped, but this message is output only if the option for
|
|
-- Multiple_Errors_Per_Line is set in Options.
|
|
|
|
package Sync is
|
|
procedure Resync_Choice;
|
|
-- Used if an error occurs scanning a choice. The scan pointer is
|
|
-- advanced to the next vertical bar, arrow, or semicolon, whichever
|
|
-- comes first. We also quit if we encounter an end of file.
|
|
|
|
procedure Resync_Expression;
|
|
-- Used if an error is detected during the parsing of an expression.
|
|
-- It skips past tokens until either a token which cannot be part of
|
|
-- an expression is encountered (an expression terminator), or if a
|
|
-- comma or right parenthesis or vertical bar is encountered at the
|
|
-- current parenthesis level (a parenthesis level counter is maintained
|
|
-- to carry out this test).
|
|
|
|
procedure Resync_Past_Semicolon;
|
|
-- Used if an error occurs while scanning a sequence of declarations.
|
|
-- The scan pointer is positioned past the next semicolon and the scan
|
|
-- resumes. The scan is also resumed on encountering a token which
|
|
-- starts a declaration (but we make sure to skip at least one token
|
|
-- in this case, to avoid getting stuck in a loop).
|
|
|
|
procedure Resync_To_Semicolon;
|
|
-- Similar to Resync_Past_Semicolon, except that the scan pointer is
|
|
-- left pointing to the semicolon rather than past it.
|
|
|
|
procedure Resync_Past_Semicolon_Or_To_Loop_Or_Then;
|
|
-- Used if an error occurs while scanning a sequence of statements. The
|
|
-- scan pointer is positioned past the next semicolon, or to the next
|
|
-- occurrence of either then or loop, and the scan resumes.
|
|
|
|
procedure Resync_To_When;
|
|
-- Used when an error occurs scanning an entry index specification. The
|
|
-- scan pointer is positioned to the next WHEN (or to IS or semicolon if
|
|
-- either of these appear before WHEN, indicating another error has
|
|
-- occurred).
|
|
|
|
procedure Resync_Semicolon_List;
|
|
-- Used if an error occurs while scanning a parenthesized list of items
|
|
-- separated by semicolons. The scan pointer is advanced to the next
|
|
-- semicolon or right parenthesis at the outer parenthesis level, or
|
|
-- to the next is or RETURN keyword occurrence, whichever comes first.
|
|
|
|
procedure Resync_Cunit;
|
|
-- Synchronize to next token which could be the start of a compilation
|
|
-- unit, or to the end of file token.
|
|
end Sync;
|
|
|
|
--------------
|
|
-- Par.Tchk --
|
|
--------------
|
|
|
|
-- Routines to check for expected tokens
|
|
|
|
package Tchk is
|
|
|
|
-- Procedures with names of the form T_xxx, where Tok_xxx is a token
|
|
-- name, check that the current token matches the required token, and
|
|
-- if so, scan past it. If not, an error is issued indicating that
|
|
-- the required token is not present (xxx expected). In most cases, the
|
|
-- scan pointer is not moved in the not-found case, but there are some
|
|
-- exceptions to this, see for example T_Id, where the scan pointer is
|
|
-- moved across a literal appearing where an identifier is expected.
|
|
|
|
procedure T_Abort;
|
|
procedure T_Arrow;
|
|
procedure T_At;
|
|
procedure T_Body;
|
|
procedure T_Box;
|
|
procedure T_Colon;
|
|
procedure T_Colon_Equal;
|
|
procedure T_Comma;
|
|
procedure T_Dot_Dot;
|
|
procedure T_For;
|
|
procedure T_Greater_Greater;
|
|
procedure T_Identifier;
|
|
procedure T_In;
|
|
procedure T_Is;
|
|
procedure T_Left_Paren;
|
|
procedure T_Loop;
|
|
procedure T_Mod;
|
|
procedure T_New;
|
|
procedure T_Of;
|
|
procedure T_Or;
|
|
procedure T_Private;
|
|
procedure T_Range;
|
|
procedure T_Record;
|
|
procedure T_Right_Paren;
|
|
procedure T_Semicolon;
|
|
procedure T_Then;
|
|
procedure T_Type;
|
|
procedure T_Use;
|
|
procedure T_When;
|
|
procedure T_With;
|
|
|
|
-- Procedures having names of the form TF_xxx, where Tok_xxx is a token
|
|
-- name check that the current token matches the required token, and
|
|
-- if so, scan past it. If not, an error message is issued indicating
|
|
-- that the required token is not present (xxx expected).
|
|
|
|
-- If the missing token is at the end of the line, then control returns
|
|
-- immediately after posting the message. If there are remaining tokens
|
|
-- on the current line, a search is conducted to see if the token
|
|
-- appears later on the current line, as follows:
|
|
|
|
-- A call to Scan_Save is issued and a forward search for the token
|
|
-- is carried out. If the token is found on the current line before a
|
|
-- semicolon, then it is scanned out and the scan continues from that
|
|
-- point. If not the scan is restored to the point where it was missing.
|
|
|
|
procedure TF_Arrow;
|
|
procedure TF_Is;
|
|
procedure TF_Loop;
|
|
procedure TF_Return;
|
|
procedure TF_Semicolon;
|
|
procedure TF_Then;
|
|
procedure TF_Use;
|
|
|
|
-- Procedures with names of the form U_xxx, where Tok_xxx is a token
|
|
-- name, are just like the corresponding T_xxx procedures except that
|
|
-- an error message, if given, is unconditional.
|
|
|
|
procedure U_Left_Paren;
|
|
procedure U_Right_Paren;
|
|
end Tchk;
|
|
|
|
--------------
|
|
-- Par.Util --
|
|
--------------
|
|
|
|
package Util is
|
|
function Bad_Spelling_Of (T : Token_Type) return Boolean;
|
|
-- This function is called in an error situation. It checks if the
|
|
-- current token is an identifier whose name is a plausible bad
|
|
-- spelling of the given keyword token, and if so, issues an error
|
|
-- message, sets Token from T, and returns True. Otherwise Token is
|
|
-- unchanged, and False is returned.
|
|
|
|
procedure Check_Bad_Layout;
|
|
-- Check for bad indentation in RM checking mode. Used for statements
|
|
-- and declarations. Checks if current token is at start of line and
|
|
-- is exdented from the current expected end column, and if so an
|
|
-- error message is generated.
|
|
|
|
procedure Check_Misspelling_Of (T : Token_Type);
|
|
pragma Inline (Check_Misspelling_Of);
|
|
-- This is similar to the function above, except that it does not
|
|
-- return a result. It is typically used in a situation where any
|
|
-- identifier is an error, and it makes sense to simply convert it
|
|
-- to the given token if it is a plausible misspelling of it.
|
|
|
|
procedure Check_95_Keyword (Token_95, Next : Token_Type);
|
|
-- This routine checks if the token after the current one matches the
|
|
-- Next argument. If so, the scan is backed up to the current token
|
|
-- and Token_Type is changed to Token_95 after issuing an appropriate
|
|
-- error message ("(Ada 83) keyword xx cannot be used"). If not,
|
|
-- the scan is backed up with Token_Type unchanged. This routine
|
|
-- is used to deal with an attempt to use a 95 keyword in Ada 83
|
|
-- mode. The caller has typically checked that the current token,
|
|
-- an identifier, matches one of the 95 keywords.
|
|
|
|
procedure Check_Simple_Expression (E : Node_Id);
|
|
-- Given an expression E, that has just been scanned, so that Expr_Form
|
|
-- is still set, outputs an error if E is a non-simple expression. E is
|
|
-- not modified by this call.
|
|
|
|
procedure Check_Simple_Expression_In_Ada_83 (E : Node_Id);
|
|
-- Like Check_Simple_Expression, except that the error message is only
|
|
-- given when operating in Ada 83 mode, and includes "in Ada 83".
|
|
|
|
function Check_Subtype_Mark (Mark : Node_Id) return Node_Id;
|
|
-- Called to check that a node representing a name (or call) is
|
|
-- suitable for a subtype mark, i.e, that it is an identifier or
|
|
-- a selected component. If so, or if it is already Error, then
|
|
-- it is returned unchanged. Otherwise an error message is issued
|
|
-- and Error is returned.
|
|
|
|
function Comma_Present return Boolean;
|
|
-- Used in comma delimited lists to determine if a comma is present, or
|
|
-- can reasonably be assumed to have been present (an error message is
|
|
-- generated in the latter case). If True is returned, the scan has been
|
|
-- positioned past the comma. If False is returned, the scan position
|
|
-- is unchanged. Note that all comma-delimited lists are terminated by
|
|
-- a right paren, so the only legitimate tokens when Comma_Present is
|
|
-- called are right paren and comma. If some other token is found, then
|
|
-- Comma_Present has the job of deciding whether it is better to pretend
|
|
-- a comma was present, post a message for a missing comma and return
|
|
-- True, or return False and let the caller diagnose the missing right
|
|
-- parenthesis.
|
|
|
|
procedure Discard_Junk_Node (N : Node_Id);
|
|
procedure Discard_Junk_List (L : List_Id);
|
|
pragma Inline (Discard_Junk_Node);
|
|
pragma Inline (Discard_Junk_List);
|
|
-- These procedures do nothing at all, their effect is simply to discard
|
|
-- the argument. A typical use is to skip by some junk that is not
|
|
-- expected in the current context.
|
|
|
|
procedure Ignore (T : Token_Type);
|
|
-- If current token matches T, then give an error message and skip
|
|
-- past it, otherwise the call has no effect at all. T may be any
|
|
-- reserved word token, or comma, left or right paren, or semicolon.
|
|
|
|
function Is_Reserved_Identifier (C : Id_Check := None) return Boolean;
|
|
-- Test if current token is a reserved identifier. This test is based
|
|
-- on the token being a keyword and being spelled in typical identifier
|
|
-- style (i.e. starting with an upper case letter). The parameter C
|
|
-- determines the special treatment if a reserved word is encountered
|
|
-- that has the normal casing of a reserved word.
|
|
|
|
procedure Merge_Identifier (Prev : Node_Id; Nxt : Token_Type);
|
|
-- Called when the previous token is an identifier (whose Token_Node
|
|
-- value is given by Prev) to check if current token is an identifier
|
|
-- that can be merged with the previous one adding an underscore. The
|
|
-- merge is only attempted if the following token matches Nxt. If all
|
|
-- conditions are met, an error message is issued, and the merge is
|
|
-- carried out, modifying the Chars field of Prev.
|
|
|
|
function Next_Token_Is (Tok : Token_Type) return Boolean;
|
|
-- Looks at token after current one and returns True if the token type
|
|
-- matches Tok. The scan is unconditionally restored on return.
|
|
|
|
procedure No_Constraint;
|
|
-- Called in a place where no constraint is allowed, but one might
|
|
-- appear due to a common error (e.g. after the type mark in a procedure
|
|
-- parameter. If a constraint is present, an error message is posted,
|
|
-- and the constraint is scanned and discarded.
|
|
|
|
procedure Push_Scope_Stack;
|
|
pragma Inline (Push_Scope_Stack);
|
|
-- Push a new entry onto the scope stack. Scope.Last (the stack pointer)
|
|
-- is incremented. The Junk field is preinitialized to False. The caller
|
|
-- is expected to fill in all remaining entries of the new top stack
|
|
-- entry at Scope.Table (Scope.Last).
|
|
|
|
procedure Pop_Scope_Stack;
|
|
-- Pop an entry off the top of the scope stack. Scope_Last (the scope
|
|
-- table stack pointer) is decremented by one. It is a fatal error to
|
|
-- try to pop off the dummy entry at the bottom of the stack (i.e.
|
|
-- Scope.Last must be non-zero at the time of call).
|
|
|
|
function Separate_Present return Boolean;
|
|
-- Determines if the current token is either Tok_Separate, or an
|
|
-- identifier that is a possible misspelling of "separate" followed
|
|
-- by a semicolon. True is returned if so, otherwise False.
|
|
|
|
procedure Signal_Bad_Attribute;
|
|
-- The current token is an identifier that is supposed to be an
|
|
-- attribute identifier but is not. This routine posts appropriate
|
|
-- error messages, including a check for a near misspelling.
|
|
|
|
function Token_Is_At_Start_Of_Line return Boolean;
|
|
pragma Inline (Token_Is_At_Start_Of_Line);
|
|
-- Determines if the current token is the first token on the line
|
|
|
|
function Token_Is_At_End_Of_Line return Boolean;
|
|
-- Determines if the current token is the last token on the line
|
|
|
|
end Util;
|
|
|
|
--------------
|
|
-- Par.Prag --
|
|
--------------
|
|
|
|
-- The processing for pragmas is split off from chapter 2
|
|
|
|
function Prag (Pragma_Node : Node_Id; Semi : Source_Ptr) return Node_Id;
|
|
-- This function is passed a tree for a pragma that has been scanned out.
|
|
-- The pragma is syntactically well formed according to the general syntax
|
|
-- for pragmas and the pragma identifier is for one of the recognized
|
|
-- pragmas. It performs specific syntactic checks for specific pragmas.
|
|
-- The result is the input node if it is OK, or Error otherwise. The
|
|
-- reason that this is separated out is to facilitate the addition
|
|
-- of implementation defined pragmas. The second parameter records the
|
|
-- location of the semicolon following the pragma (this is needed for
|
|
-- correct processing of the List and Page pragmas). The returned value
|
|
-- is a copy of Pragma_Node, or Error if an error is found. Note that
|
|
-- at the point where Prag is called, the right paren ending the pragma
|
|
-- has been scanned out, and except in the case of pragma Style_Checks,
|
|
-- so has the following semicolon. For Style_Checks, the caller delays
|
|
-- the scanning of the semicolon so that it will be scanned using the
|
|
-- settings from the Style_Checks pragma preceding it.
|
|
|
|
--------------
|
|
-- Par.Labl --
|
|
--------------
|
|
|
|
procedure Labl;
|
|
-- This procedure creates implicit label declarations for all label that
|
|
-- are declared in the current unit. Note that this could conceptually
|
|
-- be done at the point where the labels are declared, but it is tricky
|
|
-- to do it then, since the tree is not hooked up at the point where the
|
|
-- label is declared (e.g. a sequence of statements is not yet attached
|
|
-- to its containing scope at the point a label in the sequence is found)
|
|
|
|
--------------
|
|
-- Par.Load --
|
|
--------------
|
|
|
|
procedure Load;
|
|
-- This procedure loads all subsidiary units that are required by this
|
|
-- unit, including with'ed units, specs for bodies, and parents for child
|
|
-- units. It does not load bodies for inlined procedures and generics,
|
|
-- since we don't know till semantic analysis is complete what is needed.
|
|
|
|
-----------
|
|
-- Stubs --
|
|
-----------
|
|
|
|
-- The package bodies can see all routines defined in all other subpackages
|
|
|
|
use Ch2;
|
|
use Ch3;
|
|
use Ch4;
|
|
use Ch5;
|
|
use Ch6;
|
|
use Ch7;
|
|
use Ch8;
|
|
use Ch9;
|
|
use Ch10;
|
|
use Ch11;
|
|
use Ch12;
|
|
use Ch13;
|
|
|
|
use Endh;
|
|
use Tchk;
|
|
use Sync;
|
|
use Util;
|
|
|
|
package body Ch2 is separate;
|
|
package body Ch3 is separate;
|
|
package body Ch4 is separate;
|
|
package body Ch5 is separate;
|
|
package body Ch6 is separate;
|
|
package body Ch7 is separate;
|
|
package body Ch8 is separate;
|
|
package body Ch9 is separate;
|
|
package body Ch10 is separate;
|
|
package body Ch11 is separate;
|
|
package body Ch12 is separate;
|
|
package body Ch13 is separate;
|
|
|
|
package body Endh is separate;
|
|
package body Tchk is separate;
|
|
package body Sync is separate;
|
|
package body Util is separate;
|
|
|
|
function Prag (Pragma_Node : Node_Id; Semi : Source_Ptr) return Node_Id
|
|
is separate;
|
|
|
|
procedure Labl is separate;
|
|
procedure Load is separate;
|
|
|
|
-- Start of processing for Par
|
|
|
|
begin
|
|
|
|
-- Deal with configuration pragmas case first
|
|
|
|
if Configuration_Pragmas then
|
|
declare
|
|
Pragmas : constant List_Id := Empty_List;
|
|
P_Node : Node_Id;
|
|
|
|
begin
|
|
loop
|
|
if Token = Tok_EOF then
|
|
return Pragmas;
|
|
|
|
elsif Token /= Tok_Pragma then
|
|
Error_Msg_SC ("only pragmas allowed in configuration file");
|
|
return Error_List;
|
|
|
|
else
|
|
P_Node := P_Pragma;
|
|
|
|
if Nkind (P_Node) = N_Pragma then
|
|
|
|
-- Give error if bad pragma
|
|
|
|
if not Is_Configuration_Pragma_Name (Pragma_Name (P_Node))
|
|
and then Pragma_Name (P_Node) /= Name_Source_Reference
|
|
then
|
|
if Is_Pragma_Name (Pragma_Name (P_Node)) then
|
|
Error_Msg_N
|
|
("only configuration pragmas allowed " &
|
|
"in configuration file", P_Node);
|
|
else
|
|
Error_Msg_N
|
|
("unrecognized pragma in configuration file",
|
|
P_Node);
|
|
end if;
|
|
|
|
-- Pragma is OK config pragma, so collect it
|
|
|
|
else
|
|
Append (P_Node, Pragmas);
|
|
end if;
|
|
end if;
|
|
end if;
|
|
end loop;
|
|
end;
|
|
|
|
-- Normal case of compilation unit
|
|
|
|
else
|
|
Save_Opt_Config_Switches (Save_Config_Switches);
|
|
|
|
-- The following loop runs more than once in syntax check mode
|
|
-- where we allow multiple compilation units in the same file
|
|
-- and in Multiple_Unit_Per_file mode where we skip units till
|
|
-- we get to the unit we want.
|
|
|
|
for Ucount in Pos loop
|
|
Set_Opt_Config_Switches
|
|
(Is_Internal_File_Name (File_Name (Current_Source_File)),
|
|
Current_Source_Unit = Main_Unit);
|
|
|
|
-- Initialize scope table and other parser control variables
|
|
|
|
Compiler_State := Parsing;
|
|
Scope.Init;
|
|
Scope.Increment_Last;
|
|
Scope.Table (0).Etyp := E_Dummy;
|
|
SIS_Entry_Active := False;
|
|
Last_Resync_Point := No_Location;
|
|
|
|
Goto_List := New_Elmt_List;
|
|
Label_List := New_Elmt_List;
|
|
|
|
-- If in multiple unit per file mode, skip past ignored unit
|
|
|
|
if Ucount < Multiple_Unit_Index then
|
|
|
|
-- We skip in syntax check only mode, since we don't want to do
|
|
-- anything more than skip past the unit and ignore it. This means
|
|
-- we skip processing like setting up a unit table entry.
|
|
|
|
declare
|
|
Save_Operating_Mode : constant Operating_Mode_Type :=
|
|
Operating_Mode;
|
|
|
|
Save_Style_Check : constant Boolean := Style_Check;
|
|
|
|
begin
|
|
Operating_Mode := Check_Syntax;
|
|
Style_Check := False;
|
|
Discard_Node (P_Compilation_Unit);
|
|
Operating_Mode := Save_Operating_Mode;
|
|
Style_Check := Save_Style_Check;
|
|
|
|
-- If we are at an end of file, and not yet at the right unit,
|
|
-- then we have a fatal error. The unit is missing.
|
|
|
|
if Token = Tok_EOF then
|
|
Error_Msg_SC ("file has too few compilation units");
|
|
raise Unrecoverable_Error;
|
|
end if;
|
|
end;
|
|
|
|
-- Here if we are not skipping a file in multiple unit per file mode.
|
|
-- Parse the unit that we are interested in. Note that in check
|
|
-- syntax mode we are interested in all units in the file.
|
|
|
|
else
|
|
declare
|
|
Comp_Unit_Node : constant Node_Id := P_Compilation_Unit;
|
|
|
|
begin
|
|
-- If parsing was successful and we are not in check syntax
|
|
-- mode, check that language defined units are compiled in GNAT
|
|
-- mode. For this purpose we do NOT consider renamings in annex
|
|
-- J as predefined. That allows users to compile their own
|
|
-- versions of these files, and in particular, in the VMS
|
|
-- implementation, the DEC versions can be substituted for the
|
|
-- standard Ada 95 versions. Another exception is System.RPC
|
|
-- and its children. This allows a user to supply their own
|
|
-- communication layer.
|
|
|
|
if Comp_Unit_Node /= Error
|
|
and then Operating_Mode = Generate_Code
|
|
and then Current_Source_Unit = Main_Unit
|
|
and then not GNAT_Mode
|
|
then
|
|
declare
|
|
Uname : constant String :=
|
|
Get_Name_String
|
|
(Unit_Name (Current_Source_Unit));
|
|
Name : String (1 .. Uname'Length - 2);
|
|
|
|
begin
|
|
-- Because Unit_Name includes "%s"/"%b", we need to strip
|
|
-- the last two characters to get the real unit name.
|
|
|
|
Name := Uname (Uname'First .. Uname'Last - 2);
|
|
|
|
if Name = "ada" or else
|
|
Name = "interfaces" or else
|
|
Name = "system"
|
|
then
|
|
Error_Msg
|
|
("language defined units may not be recompiled",
|
|
Sloc (Unit (Comp_Unit_Node)));
|
|
|
|
elsif Name'Length > 4
|
|
and then
|
|
Name (Name'First .. Name'First + 3) = "ada."
|
|
then
|
|
Error_Msg
|
|
("descendents of package Ada " &
|
|
"may not be compiled",
|
|
Sloc (Unit (Comp_Unit_Node)));
|
|
|
|
elsif Name'Length > 11
|
|
and then
|
|
Name (Name'First .. Name'First + 10) = "interfaces."
|
|
then
|
|
Error_Msg
|
|
("descendents of package Interfaces " &
|
|
"may not be compiled",
|
|
Sloc (Unit (Comp_Unit_Node)));
|
|
|
|
elsif Name'Length > 7
|
|
and then Name (Name'First .. Name'First + 6) = "system."
|
|
and then Name /= "system.rpc"
|
|
and then
|
|
(Name'Length < 11
|
|
or else Name (Name'First .. Name'First + 10) /=
|
|
"system.rpc.")
|
|
then
|
|
Error_Msg
|
|
("descendents of package System " &
|
|
"may not be compiled",
|
|
Sloc (Unit (Comp_Unit_Node)));
|
|
end if;
|
|
end;
|
|
end if;
|
|
end;
|
|
|
|
-- All done if at end of file
|
|
|
|
exit when Token = Tok_EOF;
|
|
|
|
-- If we are not at an end of file, it means we are in syntax
|
|
-- check only mode, and we keep the loop going to parse all
|
|
-- remaining units in the file.
|
|
|
|
end if;
|
|
|
|
Restore_Opt_Config_Switches (Save_Config_Switches);
|
|
end loop;
|
|
|
|
-- Now that we have completely parsed the source file, we can complete
|
|
-- the source file table entry.
|
|
|
|
Complete_Source_File_Entry;
|
|
|
|
-- An internal error check, the scope stack should now be empty
|
|
|
|
pragma Assert (Scope.Last = 0);
|
|
|
|
-- Here we make the SCO table entries for the main unit
|
|
|
|
if Generate_SCO then
|
|
SCO_Record (Main_Unit);
|
|
end if;
|
|
|
|
-- Remaining steps are to create implicit label declarations and to load
|
|
-- required subsidiary sources. These steps are required only if we are
|
|
-- doing semantic checking.
|
|
|
|
if Operating_Mode /= Check_Syntax or else Debug_Flag_F then
|
|
Par.Labl;
|
|
Par.Load;
|
|
end if;
|
|
|
|
-- Restore settings of switches saved on entry
|
|
|
|
Restore_Opt_Config_Switches (Save_Config_Switches);
|
|
Set_Comes_From_Source_Default (False);
|
|
return Empty_List;
|
|
end if;
|
|
end Par;
|