From 275e1f080b85b0bf335375a84f6cc5ab9031c364 Mon Sep 17 00:00:00 2001
From: Stephen Heumann <stephenheumann@gmail.com>
Date: Sun, 1 Apr 2018 14:14:18 -0500
Subject: [PATCH] Add a new flag to control whether mixed declarations are
 allowed and C99 scope rules are used.

#pragma ignore bit 4 (a value of 16) now controls these. It is on by default (allowing them), but turning it off will restore the C89 rules.
---
 Header.pas  |  5 ++++-
 Parser.pas  |  2 --
 Scanner.pas | 14 ++++++++++++++
 3 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/Header.pas b/Header.pas
index ed918cd..19f93a0 100644
--- a/Header.pas
+++ b/Header.pas
@@ -864,7 +864,8 @@ procedure EndInclude {chPtr: ptr};
                      WriteByte(ord(skipIllegalTokens)
                         | (ord(allowLongIntChar) << 1)
                         | (ord(allowTokensAfterEndif) << 2)
-                        | (ord(allowSlashSlashComments) << 3));
+                        | (ord(allowSlashSlashComments) << 3)
+                        | (ord(allowMixedDeclarations) << 4));
 
                   p_segment: begin
                      for i := 1 to 10 do begin
@@ -1499,6 +1500,8 @@ var
             allowLongIntChar := odd(i >> 1);
             allowTokensAfterEndif := odd(i >> 2);
             allowSlashSlashComments := odd(i >> 3);
+            allowMixedDeclarations := odd(i >> 4);
+            c99Scope := allowMixedDeclarations;
             end;
          
          p_segment: begin
diff --git a/Parser.pas b/Parser.pas
index 422ac1e..318e022 100644
--- a/Parser.pas
+++ b/Parser.pas
@@ -81,8 +81,6 @@ implementation
 
 const
    maxBitField = 32;                    {max # of bits in a bit field}
-   allowMixedDeclarations = true;
-   c99Scope = true;
  
 type
 
diff --git a/Scanner.pas b/Scanner.pas
index 0b13888..e6302ee 100644
--- a/Scanner.pas
+++ b/Scanner.pas
@@ -85,6 +85,9 @@ var
    allowSlashSlashComments: boolean;    {allow // comments?}
    allowTokensAfterEndif: boolean;      {allow tokens after #endif?}
    skipIllegalTokens: boolean;          {skip flagging illegal tokens in skipped code?}
+                                        {Note: The following two are set together}
+   allowMixedDeclarations: boolean;     {allow mixed declarations & stmts (C99)?}
+   c99Scope: boolean;                   {follow C99 rules for block scopes?}
 
 {---------------------------------------------------------------}
 
@@ -613,6 +616,7 @@ if list or (numErr <> 0) then begin
         123: msg := @'array element type may not be an incomplete or function type';
         124: msg := @'invalid format string';
         125: msg := @'format string is not a string literal';
+        126: msg := @'scope rules may not be changed within a function';
          otherwise: Error(57);
          end; {case}
        writeln(msg^);
@@ -2792,6 +2796,7 @@ if ch in ['a','d','e','i','l','p','u','w'] then begin
                      {     2 - allow long int character constants          }
                      {     4 - allow tokens after #endif                   }
                      {     8 - allow // comments                           }
+                     {    16 - allow mixed decls & use C99 scope rules     }
                      FlagPragmas(p_ignore);
                      NumericDirective;    
                      val := long(expressionValue).lsw;
@@ -2799,6 +2804,13 @@ if ch in ['a','d','e','i','l','p','u','w'] then begin
                      allowLongIntChar := odd(val >> 1);
                      allowTokensAfterEndif := odd(val >> 2);
                      allowSlashSlashComments := odd(val >> 3);
+                     allowMixedDeclarations := odd(val >> 4);
+                     if allowMixedDeclarations <> c99Scope then begin
+                        if doingFunction then
+                           Error(126)
+                        else
+                           c99Scope := allowMixedDeclarations;
+                        end; {if}
                      if token.kind <> eolsy then
                         Error(11);
                      end {else if}
@@ -3371,6 +3383,8 @@ skipIllegalTokens := false;		{flag illegal tokens in skipped code}
 allowLongIntChar := false;		{allow long int char constants}
 allowTokensAfterEndif := false;         {allow tokens after #endif}
 allowSlashSlashComments := true;		{allow // comments}
+allowMixedDeclarations := true;         {allow mixed declarations & stmts (C99)}
+c99Scope := true;                       {follow C99 rules for block scopes}
 foundFunction := false;                 {no functions found so far}
 fileList := nil;                        {no included files}
 gettingFileName := false;               {not in GetFileName}