Re: push parser

[Joel E. Denny]

On Mon, 18 Dec 2006, Joel E. Denny wrote:

> > Thanks for looking into it.  My, there is a lot of clever code here
> > without much explanation....  But I'll give some quick feedback anyway.
> 
> I should document the push.c changes better.  I got too lazy at the end of 
> that coding session.  Maybe later today.

By the way, thanks for the feedback regardless of my laziness.

> > +   YYCOPY (&yyptr->Stack##_alloc, Stack, yysize);                  \
> > +   Stack = &yyptr->Stack##_alloc;                                  \
> > 
> > The current yacc.c doesn't use ##, since ## is not portable to K&R C.
> 
> Thanks, I think I can work around that.

Below is a small uncommitted patch against CVS Bison.  It implements a 
different solution to the above in preparation for my larger patch posted 
earlier.  Ok to commit?

Index: ChangeLog
===================================================================
RCS file: /sources/bison/bison/ChangeLog,v
retrieving revision 1.1627
diff -p -u -r1.1627 ChangeLog
--- ChangeLog   18 Dec 2006 17:27:23 -0000      1.1627
+++ ChangeLog   18 Dec 2006 21:19:07 -0000
@@ -1,3 +1,12 @@
+2006-12-18  Joel E. Denny  <address@hidden>
+
+       * data/push.c (union yyalloc): Rename yyss, yyvs, and yyls fields to
+       prevent a name collision in a future patch where these names will
+       sometimes be #define'd.
+       (YYSTACK_RELOCATE): Add an argument to select a union yyalloc field
+       since it no longer has the same name as the existing argument.
+       (yyparse or yypush_parse): Update all uses of YYSTACK_RELOCATE.
+
 2006-12-18  Paul Eggert  <address@hidden>
 
        * src/symtab.h (struct semantic_type): Remove the tag 'semantic_type',
Index: data/push.c
===================================================================
RCS file: /sources/bison/bison/data/push.c,v
retrieving revision 1.17
diff -p -u -r1.17 push.c
--- data/push.c 17 Dec 2006 01:33:31 -0000      1.17
+++ data/push.c 18 Dec 2006 21:19:07 -0000
@@ -373,9 +373,9 @@ void free (void *); /* INFRINGES ON USER
 /* A type that is properly aligned for any stack member.  */
 union yyalloc
 {
-  yytype_int16 yyss;
-  YYSTYPE yyvs;
-  ]b4_locations_if([  YYLTYPE yyls;
+  yytype_int16 yyss_alloc;
+  YYSTYPE yyvs_alloc;
+  ]b4_locations_if([  YYLTYPE yyls_alloc;
 ])dnl
 [};
 
@@ -415,12 +415,12 @@ union yyalloc
    elements in the stack, and YYPTR gives the new location of the
    stack.  Advance YYPTR to a properly aligned location for the next
    stack.  */
-# define YYSTACK_RELOCATE(Stack)                                       \
+# define YYSTACK_RELOCATE(Stack_alloc, Stack)                          \
     do                                                                 \
       {                                                                        
\
        YYSIZE_T yynewbytes;                                            \
-       YYCOPY (&yyptr->Stack, Stack, yysize);                          \
-       Stack = &yyptr->Stack;                                          \
+       YYCOPY (&yyptr->Stack_alloc, Stack, yysize);                    \
+       Stack = &yyptr->Stack_alloc;                                    \
        yynewbytes = yystacksize * sizeof (*Stack) + YYSTACK_GAP_MAXIMUM; \
        yyptr += yynewbytes / sizeof (*yyptr);                          \
       }                                                                        
\
@@ -1277,9 +1277,9 @@ m4_ifdef([b4_at_dollar_used], [[  yylsp[
          (union yyalloc *) YYSTACK_ALLOC (YYSTACK_BYTES (yystacksize));
        if (! yyptr)
          goto yyexhaustedlab;
-       YYSTACK_RELOCATE (yyss);
-       YYSTACK_RELOCATE (yyvs);
-]b4_locations_if([     YYSTACK_RELOCATE (yyls);])[
+       YYSTACK_RELOCATE (yyss_alloc, yyss);
+       YYSTACK_RELOCATE (yyvs_alloc, yyvs);
+]b4_locations_if([     YYSTACK_RELOCATE (yyls_alloc, yyls);])[
 #  undef YYSTACK_RELOCATE
        if (yyss1 != ]b4_yyssa[)
          YYSTACK_FREE (yyss1);