X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/30757c8c9355d76b2875757261c1d78e630690f4..a0af42fce6362cb02ac91613779a0afb6dc18357:/data/glr.c

diff --git a/data/glr.c b/data/glr.c
index c6fe4c3d..bc16ba1a 100644
--- a/data/glr.c
+++ b/data/glr.c
@@ -34,25 +34,30 @@ m4_define_default([b4_stack_depth_init],  [200])
 ## ------------------------ ##
 
 
+# b4_user_formals
+# ---------------
+# The possible parse-params formal arguments preceded by a comma.
+#
+# This is not shared with yacc.c in c.m4 because  GLR relies on ISO C
+# formal argument declarations.
+m4_define([b4_user_formals],
+[m4_ifset([b4_parse_param], [, b4_c_ansi_formals(b4_parse_param)])])
+
+
 # b4_lex_param
 # ------------
 # Accumule in b4_lex_param all the yylex arguments.
 # Yes, this is quite ugly...
 m4_define([b4_lex_param],
-m4_dquote(b4_pure_if([[[[YYSTYPE *]], [[yylvalp]]][]dnl
-b4_location_if([, [[YYLTYPE *], [yyllocp]]])])dnl
+m4_dquote(b4_pure_if([[[[YYSTYPE *]], [[&yylval]]][]dnl
+b4_location_if([, [[YYLTYPE *], [&yylloc]]])])dnl
 m4_ifdef([b4_lex_param], [, ]b4_lex_param)))
 
 
-# b4_user_formals
-# ---------------
-m4_define([b4_user_formals],
-[m4_ifset([b4_parse_param], [, b4_c_ansi_formals(b4_parse_param)])])
-
-
 # b4_yyerror_args
 # ---------------
-# Arguments passed to yyerror: user args plus yylloc.
+# Optional effective arguments passed to yyerror: user args plus yylloc, and
+# a trailing comma.
 m4_define([b4_yyerror_args],
 [b4_pure_if([b4_location_if([yylocp, ])])dnl
 m4_ifset([b4_parse_param], [b4_c_args(b4_parse_param), ])])
@@ -60,33 +65,33 @@ m4_ifset([b4_parse_param], [b4_c_args(b4_parse_param), ])])
 
 # b4_lyyerror_args
 # ----------------
-# Same as above, but on the look-ahead, hence yyllocp instead of yylocp.
+# Same as above, but on the look-ahead, hence &yylloc instead of yylocp.
 m4_define([b4_lyyerror_args],
-[b4_pure_if([b4_location_if([yyllocp, ])])dnl
+[b4_pure_if([b4_location_if([&yylloc, ])])dnl
 m4_ifset([b4_parse_param], [b4_c_args(b4_parse_param), ])])
 
 
 # b4_pure_args
 # ------------
-# Arguments needed by yyerror: user args plus yylloc.
+# Same as b4_yyerror_args, but with a leading comma.
 m4_define([b4_pure_args],
 [b4_pure_if([b4_location_if([, yylocp])])[]b4_user_args])
 
 
+# b4_lpure_args
+# -------------
+# Same as above, but on the look-ahead, hence &yylloc instead of yylocp.
+m4_define([b4_lpure_args],
+[b4_pure_if([b4_location_if([, &yylloc])])[]b4_user_args])
+
+
 # b4_pure_formals
 # ---------------
-# Arguments passed to yyerror: user formals plus yyllocp.
+# Arguments passed to yyerror: user formals plus yylocp.
 m4_define([b4_pure_formals],
 [b4_pure_if([b4_location_if([, YYLTYPE *yylocp])])[]b4_user_formals])
 
 
-# b4_lpure_args
-# -------------
-# Same as above, but on the look-ahead, hence yyllocp instead of yylocp.
-m4_define([b4_lpure_args],
-[b4_pure_if([b4_location_if([, yyllocp])])[]b4_user_args])
-
-
 # b4_lpure_formals
 # ----------------
 # Same as above, but on the look-ahead, hence yyllocp instead of yylocp.
@@ -111,7 +116,7 @@ m4_define([b4_lhs_value],
 # Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
 # symbols on RHS.
 m4_define([b4_rhs_value],
-[(((yyGLRStackItem const *)yyvsp)@{YYFILL (m4_eval([$2 - $1]))@}.yystate.yysemantics.yysval[]m4_ifval([$3], [.$3]))])
+[(((yyGLRStackItem const *)yyvsp)@{YYFILL (($2) - ($1))@}.yystate.yysemantics.yysval[]m4_ifval([$3], [.$3]))])
 
 
 
@@ -131,7 +136,13 @@ m4_define([b4_lhs_location],
 # Expansion of @NUM, where the current rule has RULE-LENGTH symbols
 # on RHS.
 m4_define([b4_rhs_location],
-[(((yyGLRStackItem const *)yyvsp)@{YYFILL (m4_eval([$2 - $1]))@}.yystate.yyloc)])
+[(((yyGLRStackItem const *)yyvsp)@{YYFILL (($2) - ($1))@}.yystate.yyloc)])
+
+
+
+## -------------- ##
+## Output files.  ##
+## -------------- ##
 
 # We do want M4 expansion after # for CPP macros.
 m4_changecom()
@@ -140,9 +151,10 @@ m4_divert(0)dnl
 b4_copyright([Skeleton parser for GLR parsing with Bison],
   [2002, 2003, 2004, 2005])
 [
-/* This is the parser code for GLR (Generalized LR) parser. */
+/* This is the parser code for GLR (Generalized LR) parser.  */
 
 ]b4_identification
+
 m4_if(b4_prefix[], [yy], [],
 [/* Substitute the variable and function names.  */
 #define yyparse b4_prefix[]parse
@@ -152,29 +164,21 @@ m4_if(b4_prefix[], [yy], [],
 #define yychar  b4_prefix[]char
 #define yydebug b4_prefix[]debug
 #define yynerrs b4_prefix[]nerrs
-#define yylloc b4_prefix[]lloc])
+#define yylloc  b4_prefix[]lloc])
 
-b4_token_defines(b4_tokens)
+dnl # b4_shared_declarations
+dnl # ----------------------
+dnl # Declaration that might either go into the header (if --defines)
+dnl # or open coded in the parser body.
+m4_define([b4_shared_declarations],
+[b4_token_enums(b4_tokens)[
 
 /* Copy the first part of user declarations.  */
-b4_pre_prologue[
-
-/* Enabling traces.  */
-#ifndef YYDEBUG
-# define YYDEBUG ]b4_debug[
-#endif
-
-/* Enabling verbose error messages.  */
-#ifdef YYERROR_VERBOSE
-# undef YYERROR_VERBOSE
-# define YYERROR_VERBOSE 1
-#else
-# define YYERROR_VERBOSE ]b4_error_verbose[
-#endif
+]b4_pre_prologue[
 
 #if ! defined (YYSTYPE) && ! defined (YYSTYPE_IS_DECLARED)
 ]m4_ifdef([b4_stype],
-[b4_syncline([b4_stype_line], [b4_filename])
+[b4_syncline([b4_stype_line], [b4_file_name])
 typedef union m4_bregexp(b4_stype, [^{], [YYSTYPE ])b4_stype YYSTYPE;
 /* Line __line__ of glr.c.  */
 b4_syncline([@oline@], [@ofile@])],
@@ -198,12 +202,35 @@ typedef struct YYLTYPE
 # define YYLTYPE_IS_DECLARED 1
 # define YYLTYPE_IS_TRIVIAL 1
 #endif
+]])
+
+m4_if(b4_defines_flag, 0,
+      [b4_shared_declarations],
+      [#include @output_header_name@])[
+
+/* Enabling traces.  */
+#ifndef YYDEBUG
+# define YYDEBUG ]b4_debug[
+#endif
+
+/* Enabling verbose error messages.  */
+#ifdef YYERROR_VERBOSE
+# undef YYERROR_VERBOSE
+# define YYERROR_VERBOSE 1
+#else
+# define YYERROR_VERBOSE ]b4_error_verbose[
+#endif
+
+/* Enabling the token table.  */
+#ifndef YYTOKEN_TABLE
+# define YYTOKEN_TABLE ]b4_token_table[
+#endif
 
 /* Default (constant) value used for initialization for null
    right-hand sides.  Unlike the standard yacc.c template,
    here we set the default value of $$ to a zeroed-out value.
    Since the default value is undefined, this behavior is
-   technically correct. */
+   technically correct.  */
 static YYSTYPE yyval_default;
 
 /* Copy the second part of user declarations.  */
@@ -216,7 +243,6 @@ b4_syncline([@oline@], [@ofile@])
 #include <stdlib.h>
 #include <string.h>
 #include <stdarg.h>
-#include <setjmp.h>
 
 #ifndef YY_
 # if YYENABLE_NLS
@@ -230,6 +256,23 @@ b4_syncline([@oline@], [@ofile@])
 # endif
 #endif
 
+/* Suppress unused-variable warnings by "using" E.  */
+#ifndef lint
+# define YYUSE(e) ((void) (e))
+#else
+# define YYUSE(e) /* empty */
+#endif
+
+/* Identity function, used to suppress warnings about constant conditions.  */
+#ifndef lint
+# define YYID(n) (n)
+#else
+]b4_c_function_def([YYID], [static int], [[int i], [i]])[
+{
+  return i;
+}
+#endif
+
 #ifndef YYFREE
 # define YYFREE free
 #endif
@@ -250,50 +293,53 @@ b4_syncline([@oline@], [@ofile@])
 #define yytrue 1
 #define yyfalse 0
 
+#ifndef YYSETJMP
+# include <setjmp.h>
+# define YYJMP_BUF jmp_buf
+# define YYSETJMP(env) setjmp (env)
+# define YYLONGJMP(env, val) longjmp (env, val)
+#endif
+
 /*-----------------.
 | GCC extensions.  |
 `-----------------*/
 
 #ifndef __attribute__
 /* This feature is available in gcc versions 2.5 and later.  */
-# if !defined (__GNUC__) || __GNUC__ < 2 || \
-(__GNUC__ == 2 && __GNUC_MINOR__ < 5) || __STRICT_ANSI__
+# if (!defined (__GNUC__) || __GNUC__ < 2 \
+      || (__GNUC__ == 2 && __GNUC_MINOR__ < 5) || __STRICT_ANSI__)
 #  define __attribute__(Spec) /* empty */
-# else
-]b4_location_if([#  define YYOPTIONAL_LOC(Name) Name],[
-#  if defined (__cplusplus)
-#   define YYOPTIONAL_LOC(Name) /* empty */
-#  else
-#   define YYOPTIONAL_LOC(Name) Name ATTRIBUTE_UNUSED
-#  endif])[
 # endif
 #endif
 
+]b4_location_if([#define YYOPTIONAL_LOC(Name) Name],[
+#ifdef __cplusplus
+# define YYOPTIONAL_LOC(Name) /* empty */
+#else
+# define YYOPTIONAL_LOC(Name) Name __attribute__ ((__unused__))
+#endif])[
+
 #ifndef YYASSERT
 # define YYASSERT(condition) ((void) ((condition) || (abort (), 0)))
 #endif
 
-#ifndef ATTRIBUTE_UNUSED
-# define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
-#endif
-
-/* YYFINAL -- State number of the termination state. */
+/* YYFINAL -- State number of the termination state.  */
 #define YYFINAL  ]b4_final_state_number[
 /* YYLAST -- Last index in YYTABLE.  */
 #define YYLAST   ]b4_last[
 
-/* YYNTOKENS -- Number of terminals. */
+/* YYNTOKENS -- Number of terminals.  */
 #define YYNTOKENS  ]b4_tokens_number[
-/* YYNNTS -- Number of nonterminals. */
+/* YYNNTS -- Number of nonterminals.  */
 #define YYNNTS  ]b4_nterms_number[
-/* YYNRULES -- Number of rules. */
+/* YYNRULES -- Number of rules.  */
 #define YYNRULES  ]b4_rules_number[
-/* YYNRULES -- Number of states. */
+/* YYNRULES -- Number of states.  */
 #define YYNSTATES  ]b4_states_number[
-/* YYMAXRHS -- Maximum number of symbols on right-hand side of rule. */
+/* YYMAXRHS -- Maximum number of symbols on right-hand side of rule.  */
 #define YYMAXRHS ]b4_r2_max[
 /* YYMAXLEFT -- Maximum number of symbols to the left of a handle
-   accessed by $0, $-1, etc., in any rule. */
+   accessed by $0, $-1, etc., in any rule.  */
 #define YYMAXLEFT ]b4_max_left_semantic_context[
 
 /* YYTRANSLATE(X) -- Bison symbol number corresponding to X.  */
@@ -318,7 +364,7 @@ static const ]b4_int_type_for([b4_prhs])[ yyprhs[] =
   ]b4_prhs[
 };
 
-/* YYRHS -- A `-1'-separated list of the rules' RHS. */
+/* YYRHS -- A `-1'-separated list of the rules' RHS.  */
 static const ]b4_int_type_for([b4_rhs])[ yyrhs[] =
 {
   ]b4_rhs[
@@ -331,9 +377,9 @@ static const ]b4_int_type_for([b4_rline])[ yyrline[] =
 };
 #endif
 
-#if (YYDEBUG) || YYERROR_VERBOSE
-/* YYTNME[SYMBOL-NUM] -- String name of the symbol SYMBOL-NUM.
-   First, the terminals, then, starting at YYNTOKENS, nonterminals. */
+#if YYDEBUG || YYERROR_VERBOSE || YYTOKEN_TABLE
+/* YYTNAME[SYMBOL-NUM] -- String name of the symbol SYMBOL-NUM.
+   First, the terminals, then, starting at YYNTOKENS, nonterminals.  */
 static const char *const yytname[] =
 {
   ]b4_tname[
@@ -352,13 +398,13 @@ static const ]b4_int_type_for([b4_r2])[ yyr2[] =
   ]b4_r2[
 };
 
-/* YYDPREC[RULE-NUM] -- Dynamic precedence of rule #RULE-NUM (0 if none). */
+/* YYDPREC[RULE-NUM] -- Dynamic precedence of rule #RULE-NUM (0 if none).  */
 static const ]b4_int_type_for([b4_dprec])[ yydprec[] =
 {
   ]b4_dprec[
 };
 
-/* YYMERGER[RULE-NUM] -- Index of merging function for rule #RULE-NUM. */
+/* YYMERGER[RULE-NUM] -- Index of merging function for rule #RULE-NUM.  */
 static const ]b4_int_type_for([b4_merger])[ yymerger[] =
 {
   ]b4_merger[
@@ -372,7 +418,7 @@ static const ]b4_int_type_for([b4_defact])[ yydefact[] =
   ]b4_defact[
 };
 
-/* YYPDEFGOTO[NTERM-NUM]. */
+/* YYPDEFGOTO[NTERM-NUM].  */
 static const ]b4_int_type_for([b4_defgoto])[ yydefgoto[] =
 {
   ]b4_defgoto[
@@ -449,7 +495,7 @@ static const ]b4_int_type_for([b4_stos])[ yystos[] =
 #ifndef YYLLOC_DEFAULT
 # define YYLLOC_DEFAULT(Current, Rhs, N)				\
     do									\
-      if (N)								\
+      if (YYID (N))                                                    \
 	{								\
 	  (Current).first_line   = YYRHSLOC (Rhs, 1).first_line;	\
 	  (Current).first_column = YYRHSLOC (Rhs, 1).first_column;	\
@@ -463,7 +509,7 @@ static const ]b4_int_type_for([b4_stos])[ yystos[] =
 	  (Current).first_column = (Current).last_column =		\
 	    YYRHSLOC (Rhs, 0).last_column;				\
 	}								\
-    while (0)
+    while (YYID (0))
 
 /* YY_LOCATION_PRINT -- Print the location on the stream.
    This macro was not mandated originally: define only if we know
@@ -471,8 +517,8 @@ static const ]b4_int_type_for([b4_stos])[ yystos[] =
 
 # define YY_LOCATION_PRINT(File, Loc)			\
     fprintf (File, "%d.%d-%d.%d",			\
-             (Loc).first_line, (Loc).first_column,	\
-             (Loc).last_line,  (Loc).last_column)
+	     (Loc).first_line, (Loc).first_column,	\
+	     (Loc).last_line,  (Loc).last_column)
 #endif
 ]],[
 #ifndef YYLLOC_DEFAULT
@@ -491,9 +537,18 @@ static const ]b4_int_type_for([b4_stos])[ yystos[] =
 ]b4_pure_if(
 [
 #undef yynerrs
-#define yynerrs (yystack->yyerrcnt)
+#define yynerrs (yystackp->yyerrcnt)
 #undef yychar
-#define yychar (yystack->yyrawchar)],
+#define yychar (yystackp->yyrawchar)
+#undef yylval
+#define yylval (yystackp->yyval)
+#undef yylloc
+#define yylloc (yystackp->yyloc)
+m4_if(b4_prefix[], [yy], [],
+[#define b4_prefix[]nerrs yynerrs
+#define b4_prefix[]char yychar
+#define b4_prefix[]lval yylval
+#define b4_prefix[]lloc yylloc])],
 [YYSTYPE yylval;
 
 YYLTYPE yylloc;
@@ -508,7 +563,7 @@ typedef enum { yyok, yyaccept, yyabort, yyerr } YYRESULTTAG;
 
 #define YYCHK(YYE)							     \
    do { YYRESULTTAG yyflag = YYE; if (yyflag != yyok) return yyflag; }	     \
-   while (0)
+   while (YYID (0))
 
 #if YYDEBUG
 
@@ -520,19 +575,20 @@ typedef enum { yyok, yyaccept, yyabort, yyerr } YYRESULTTAG;
 do {						\
   if (yydebug)					\
     YYFPRINTF Args;				\
-} while (0)
+} while (YYID (0))
 
-]b4_yysymprint_generate([b4_c_ansi_function_def])[
+]b4_yy_symbol_print_generate([b4_c_ansi_function_def])[
 
-# define YY_SYMBOL_PRINT(Title, Type, Value, Location)		\
-do {								\
-  if (yydebug)							\
-    {								\
-      YYFPRINTF (stderr, "%s ", Title);				\
-      yysymprint (stderr,					\
-                  Type, Value]b4_location_if([, Location])[);	\
-    }								\
-} while (0)
+# define YY_SYMBOL_PRINT(Title, Type, Value, Location)			    \
+do {									    \
+  if (yydebug)								    \
+    {									    \
+      YYFPRINTF (stderr, "%s ", Title);					    \
+      yy_symbol_print (stderr,						    \
+		  Type, Value]b4_location_if([, Location])[]b4_user_args[); \
+      YYFPRINTF (stderr, "\n");						    \
+    }									    \
+} while (YYID (0))
 
 /* Nonzero means print parse trace.  It is left uninitialized so that
    multiple parsers can coexist.  */
@@ -565,7 +621,7 @@ int yydebug;
    allocation.  This is to allow allocation and initialization
    to be completed by functions that call yyexpandGLRStack before the
    stack is expanded, thus insuring that all necessary pointers get
-   properly redirected to new data. */
+   properly redirected to new data.  */
 #define YYHEADROOM 2
 
 #ifndef YYSTACKEXPANDABLE
@@ -578,6 +634,21 @@ int yydebug;
 # endif
 #endif
 
+#if YYSTACKEXPANDABLE
+# define YY_RESERVE_GLRSTACK(Yystack)			\
+  do {							\
+    if (Yystack->yyspaceLeft < YYHEADROOM)		\
+      yyexpandGLRStack (Yystack);			\
+  } while (YYID (0))
+#else
+# define YY_RESERVE_GLRSTACK(Yystack)			\
+  do {							\
+    if (Yystack->yyspaceLeft < YYHEADROOM)		\
+      yyMemoryExhausted (Yystack);			\
+  } while (YYID (0))
+#endif
+
+
 #if YYERROR_VERBOSE
 
 # ifndef yystpcpy
@@ -600,6 +671,54 @@ yystpcpy (char *yydest, const char *yysrc)
 #  endif
 # endif
 
+# ifndef yytnamerr
+/* Copy to YYRES the contents of YYSTR after stripping away unnecessary
+   quotes and backslashes, so that it's suitable for yyerror.  The
+   heuristic is that double-quoting is unnecessary unless the string
+   contains an apostrophe, a comma, or backslash (other than
+   backslash-backslash).  YYSTR is taken from yytname.  If YYRES is
+   null, do not copy; instead, return the length of what the result
+   would have been.  */
+static size_t
+yytnamerr (char *yyres, const char *yystr)
+{
+  if (*yystr == '"')
+    {
+      size_t yyn = 0;
+      char const *yyp = yystr;
+
+      for (;;)
+	switch (*++yyp)
+	  {
+	  case '\'':
+	  case ',':
+	    goto do_not_strip_quotes;
+
+	  case '\\':
+	    if (*++yyp != '\\')
+	      goto do_not_strip_quotes;
+	    /* Fall through.  */
+	  default:
+	    if (yyres)
+	      yyres[yyn] = *yyp;
+	    yyn++;
+	    break;
+
+	  case '"':
+	    if (yyres)
+	      yyres[yyn] = '\0';
+	    return yyn;
+	  }
+    do_not_strip_quotes: ;
+    }
+
+  if (! yyres)
+    return strlen (yystr);
+
+  return yystpcpy (yyres, yystr) - yyres;
+}
+# endif
+
 #endif /* !YYERROR_VERBOSE */
 
 /** State numbers, as in LALR(1) machine */
@@ -615,18 +734,18 @@ typedef short int yySymbol;
 typedef short int yyItemNum;
 
 typedef struct yyGLRState yyGLRState;
+typedef struct yyGLRStateSet yyGLRStateSet;
 typedef struct yySemanticOption yySemanticOption;
 typedef union yyGLRStackItem yyGLRStackItem;
 typedef struct yyGLRStack yyGLRStack;
-typedef struct yyGLRStateSet yyGLRStateSet;
 
 struct yyGLRState {
-  /** Type tag: always true. */
+  /** Type tag: always true.  */
   yybool yyisState;
-  /** Type tag for yysemantics. If true, yysval applies, otherwise
-   *  yyfirstVal applies. */
+  /** Type tag for yysemantics.  If true, yysval applies, otherwise
+   *  yyfirstVal applies.  */
   yybool yyresolved;
-  /** Number of corresponding LALR(1) machine state. */
+  /** Number of corresponding LALR(1) machine state.  */
   yyStateNum yylrState;
   /** Preceding state in this stack */
   yyGLRState* yypred;
@@ -635,12 +754,12 @@ struct yyGLRState {
   union {
     /** First in a chain of alternative reductions producing the
      *  non-terminal corresponding to this state, threaded through
-     *  yynext. */
+     *  yynext.  */
     yySemanticOption* yyfirstVal;
-    /** Semantic value for this state. */
+    /** Semantic value for this state.  */
     YYSTYPE yysval;
   } yysemantics;
-  /** Source location for this state. */
+  /** Source location for this state.  */
   YYLTYPE yyloc;
 };
 
@@ -650,19 +769,19 @@ struct yyGLRStateSet {
 };
 
 struct yySemanticOption {
-  /** Type tag: always false. */
+  /** Type tag: always false.  */
   yybool yyisState;
   /** Rule number for this reduction */
   yyRuleNum yyrule;
-  /** The last RHS state in the list of states to be reduced. */
+  /** The last RHS state in the list of states to be reduced.  */
   yyGLRState* yystate;
-  /** Next sibling in chain of options. To facilitate merging,
-   *  options are chained in decreasing order by address. */
+  /** Next sibling in chain of options.  To facilitate merging,
+   *  options are chained in decreasing order by address.  */
   yySemanticOption* yynext;
 };
 
-/** Type of the items in the GLR stack. The yyisState field
- *  indicates which item of the union is valid. */
+/** Type of the items in the GLR stack.  The yyisState field
+ *  indicates which item of the union is valid.  */
 union yyGLRStackItem {
   yyGLRState yystate;
   yySemanticOption yyoption;
@@ -676,9 +795,11 @@ struct yyGLRStack {
 [
   int yyerrcnt;
   int yyrawchar;
+  YYSTYPE yyval;
+  YYLTYPE yyloc;
 ])[
   yySymbol* yytokenp;
-  jmp_buf yyexception_buffer;
+  YYJMP_BUF yyexception_buffer;
   yyGLRStackItem* yyitems;
   yyGLRStackItem* yynextFree;
   size_t yyspaceLeft;
@@ -687,20 +808,26 @@ struct yyGLRStack {
   yyGLRStateSet yytops;
 };
 
-static void yyexpandGLRStack (yyGLRStack* yystack]b4_pure_formals[);
+#if YYSTACKEXPANDABLE
+static void yyexpandGLRStack (yyGLRStack* yystackp);
+#endif
 
+static void yyFail (yyGLRStack* yystackp]b4_pure_formals[, const char* yymsg)
+  __attribute__ ((__noreturn__));
 static void
-yyFail (yyGLRStack* yystack]b4_pure_formals[, const char* yymsg)
+yyFail (yyGLRStack* yystackp]b4_pure_formals[, const char* yymsg)
 {
   if (yymsg != NULL)
     yyerror (]b4_yyerror_args[yymsg);
-  longjmp (yystack->yyexception_buffer, 1);
+  YYLONGJMP (yystackp->yyexception_buffer, 1);
 }
 
+static void yyMemoryExhausted (yyGLRStack* yystackp)
+  __attribute__ ((__noreturn__));
 static void
-yyStackOverflow (yyGLRStack* yystack]b4_pure_formals[)
+yyMemoryExhausted (yyGLRStack* yystackp)
 {
-  longjmp (yystack->yyexception_buffer, 2);
+  YYLONGJMP (yystackp->yyexception_buffer, 2);
 }
 
 #if YYDEBUG || YYERROR_VERBOSE
@@ -717,9 +844,8 @@ yytokenName (yySymbol yytoken)
 
 /** Fill in YYVSP[YYLOW1 .. YYLOW0-1] from the chain of states starting
  *  at YYVSP[YYLOW0].yystate.yypred.  Leaves YYVSP[YYLOW1].yystate.yypred
- *  containing the pointer to the next state in the chain. Assumes
- *  YYLOW1 < YYLOW0.  */
-static void yyfillin (yyGLRStackItem *, int, int) ATTRIBUTE_UNUSED;
+ *  containing the pointer to the next state in the chain.  */
+static void yyfillin (yyGLRStackItem *, int, int) __attribute__ ((__unused__));
 static void
 yyfillin (yyGLRStackItem *yyvsp, int yylow0, int yylow1)
 {
@@ -737,10 +863,10 @@ yyfillin (yyGLRStackItem *yyvsp, int yylow0, int yylow1)
 }
 
 /* Do nothing if YYNORMAL or if *YYLOW <= YYLOW1.  Otherwise, fill in
-   YYVSP[YYLOW1 .. *YYLOW-1] as in yyfillin and set *YYLOW = YYLOW1.
-   For convenience, always return YYLOW1.  */
+ * YYVSP[YYLOW1 .. *YYLOW-1] as in yyfillin and set *YYLOW = YYLOW1.
+ * For convenience, always return YYLOW1.  */
 static inline int yyfill (yyGLRStackItem *, int *, int, yybool)
-     ATTRIBUTE_UNUSED;
+     __attribute__ ((__unused__));
 static inline int
 yyfill (yyGLRStackItem *yyvsp, int *yylow, int yylow1, yybool yynormal)
 {
@@ -755,20 +881,21 @@ yyfill (yyGLRStackItem *yyvsp, int *yylow, int yylow1, yybool yynormal)
 /** Perform user action for rule number YYN, with RHS length YYRHSLEN,
  *  and top stack item YYVSP.  YYLVALP points to place to put semantic
  *  value ($$), and yylocp points to place for location information
- *  (@@$). Returns yyok for normal return, yyaccept for YYACCEPT,
- *  yyerr for YYERROR, yyabort for YYABORT. */
-static YYRESULTTAG
+ *  (@@$).  Returns yyok for normal return, yyaccept for YYACCEPT,
+ *  yyerr for YYERROR, yyabort for YYABORT.  */
+/*ARGSUSED*/ static YYRESULTTAG
 yyuserAction (yyRuleNum yyn, int yyrhslen, yyGLRStackItem* yyvsp,
 	      YYSTYPE* yyvalp,
 	      YYLTYPE* YYOPTIONAL_LOC (yylocp),
-	      yyGLRStack* yystack
-              ]b4_user_formals[)
+	      yyGLRStack* yystackp
+	      ]b4_user_formals[)
 {
-  yybool yynormal ATTRIBUTE_UNUSED = (yystack->yysplitPoint == NULL);
+  yybool yynormal __attribute__ ((__unused__)) =
+    (yystackp->yysplitPoint == NULL);
   int yylow;
-
-# undef yyerrok
-# define yyerrok (yystack->yyerrState = 0)
+]b4_parse_param_use[]dnl
+[# undef yyerrok
+# define yyerrok (yystackp->yyerrState = 0)
 # undef YYACCEPT
 # define YYACCEPT return yyaccept
 # undef YYABORT
@@ -776,9 +903,9 @@ yyuserAction (yyRuleNum yyn, int yyrhslen, yyGLRStackItem* yyvsp,
 # undef YYERROR
 # define YYERROR return yyerrok, yyerr
 # undef YYRECOVERING
-# define YYRECOVERING (yystack->yyerrState != 0)
+# define YYRECOVERING (yystackp->yyerrState != 0)
 # undef yyclearin
-# define yyclearin (yychar = *(yystack->yytokenp) = YYEMPTY)
+# define yyclearin (yychar = *(yystackp->yytokenp) = YYEMPTY)
 # undef YYFILL
 # define YYFILL(N) yyfill (yyvsp, &yylow, N, yynormal)
 # undef YYBACKUP
@@ -792,11 +919,13 @@ yyuserAction (yyRuleNum yyn, int yyrhslen, yyGLRStackItem* yyvsp,
   else
     *yyvalp = yyvsp[YYFILL (1-yyrhslen)].yystate.yysemantics.yysval;
   YYLLOC_DEFAULT (*yylocp, yyvsp - yyrhslen, yyrhslen);
-]b4_location_if([[  yystack->yyerror_range[1].yystate.yyloc = *yylocp;
-]])
+]b4_location_if([[  yystackp->yyerror_range[1].yystate.yyloc = *yylocp;
+]])[
   switch (yyn)
     {
-      b4_actions
+      ]b4_actions
+/* Line __line__ of glr.c.  */
+b4_syncline([@oline@], [@ofile@])[
       default: break;
     }
 
@@ -808,37 +937,65 @@ yyuserAction (yyRuleNum yyn, int yyrhslen, yyGLRStackItem* yyvsp,
 # undef YYBACKUP
 # undef yyclearin
 # undef YYRECOVERING
-/* Line __line__ of glr.c.  */
-b4_syncline([@oline@], [@ofile@])
 }
 
 
-static void
+/*ARGSUSED*/ static void
 yyuserMerge (int yyn, YYSTYPE* yy0, YYSTYPE* yy1)
 {
-  /* `Use' the arguments.  */
-  (void) yy0;
-  (void) yy1;
+  YYUSE (yy0);
+  YYUSE (yy1);
 
   switch (yyn)
     {
-      b4_mergers
+      ]b4_mergers[
       default: break;
     }
 }
-[
+
 			      /* Bison grammar-table manipulation.  */
 
 ]b4_yydestruct_generate([b4_c_ansi_function_def])[
 
-/** Number of symbols composing the right hand side of rule #RULE. */
+/** Number of symbols composing the right hand side of rule #RULE.  */
 static inline int
 yyrhsLength (yyRuleNum yyrule)
 {
   return yyr2[yyrule];
 }
 
-/** Left-hand-side symbol for rule #RULE. */
+static void
+yydestroyGLRState (char const *yymsg, yyGLRState *yys]b4_user_formals[)
+{
+  if (yys->yyresolved)
+    yydestruct (yymsg, yystos[yys->yylrState],
+		&yys->yysemantics.yysval]b4_location_if([, &yys->yyloc])[]b4_user_args[);
+  else
+    {
+#if YYDEBUG
+      if (yydebug)
+	{
+	  YYFPRINTF (stderr, "%s unresolved ", yymsg);
+	  yy_symbol_print (stderr, yystos[yys->yylrState],
+		      &yys->yysemantics.yysval]b4_location_if([, &yys->yyloc])[]b4_user_args[);
+	  YYFPRINTF (stderr, "\n");
+	}
+#endif
+
+      if (yys->yysemantics.yyfirstVal)
+	{
+	  yySemanticOption *yyoption = yys->yysemantics.yyfirstVal;
+	  yyGLRState *yyrh;
+	  int yyn;
+	  for (yyrh = yyoption->yystate, yyn = yyrhsLength (yyoption->yyrule);
+	       yyn > 0;
+	       yyrh = yyrh->yypred, yyn -= 1)
+	    yydestroyGLRState (yymsg, yyrh]b4_user_args[);
+	}
+    }
+}
+
+/** Left-hand-side symbol for rule #RULE.  */
 static inline yySymbol
 yylhsNonterm (yyRuleNum yyrule)
 {
@@ -846,19 +1003,19 @@ yylhsNonterm (yyRuleNum yyrule)
 }
 
 #define yyis_pact_ninf(yystate) \
-  ]m4_if(m4_eval(b4_pact_ninf < b4_pact_min), 1,
-	 0,
-	 ((yystate) == YYPACT_NINF))[
+  ]m4_if(m4_eval(b4_pact_ninf < b4_pact_min), [1],
+	 [0],
+	 [((yystate) == YYPACT_NINF)])[
 
 /** True iff LR state STATE has only a default reduction (regardless
- *  of token). */
+ *  of token).  */
 static inline yybool
 yyisDefaultedState (yyStateNum yystate)
 {
   return yyis_pact_ninf (yypact[yystate]);
 }
 
-/** The default reduction for STATE, assuming it has one. */
+/** The default reduction for STATE, assuming it has one.  */
 static inline yyRuleNum
 yydefaultAction (yyStateNum yystate)
 {
@@ -866,9 +1023,9 @@ yydefaultAction (yyStateNum yystate)
 }
 
 #define yyis_table_ninf(yytable_value) \
-  ]m4_if(m4_eval(b4_table_ninf < b4_table_min), 1,
-	 0,
-	 ((yytable_value) == YYTABLE_NINF))[
+  ]m4_if(m4_eval(b4_table_ninf < b4_table_min), [1],
+	 [YYID (0)],
+	 [((yytable_value) == YYTABLE_NINF)])[
 
 /** Set *YYACTION to the action to take in YYSTATE on seeing YYTOKEN.
  *  Result R means
@@ -880,7 +1037,7 @@ yydefaultAction (yyStateNum yystate)
  */
 static inline void
 yygetLRActions (yyStateNum yystate, int yytoken,
-	        int* yyaction, const short int** yyconflicts)
+		int* yyaction, const short int** yyconflicts)
 {
   int yyindex = yypact[yystate] + yytoken;
   if (yyindex < 0 || YYLAST < yyindex || yycheck[yyindex] != yytoken)
@@ -925,26 +1082,37 @@ yyisErrorAction (int yyaction)
 
 				/* GLRStates */
 
+/** Return a fresh GLRStackItem.  Callers should call
+ * YY_RESERVE_GLRSTACK afterwards to make sure there is sufficient
+ * headroom.  */
+
+static inline yyGLRStackItem*
+yynewGLRStackItem (yyGLRStack* yystackp, yybool yyisState)
+{
+  yyGLRStackItem* yynewItem = yystackp->yynextFree;
+  yystackp->yyspaceLeft -= 1;
+  yystackp->yynextFree += 1;
+  yynewItem->yystate.yyisState = yyisState;
+  return yynewItem;
+}
+
 static void
-yyaddDeferredAction (yyGLRStack* yystack, yyGLRState* yystate,
-		     yyGLRState* rhs, yyRuleNum yyrule]b4_pure_formals[)
-{
-  yySemanticOption* yynewItem;
-  yynewItem = &yystack->yynextFree->yyoption;
-  yystack->yyspaceLeft -= 1;
-  yystack->yynextFree += 1;
-  yynewItem->yyisState = yyfalse;
-  yynewItem->yystate = rhs;
-  yynewItem->yyrule = yyrule;
-  yynewItem->yynext = yystate->yysemantics.yyfirstVal;
-  yystate->yysemantics.yyfirstVal = yynewItem;
-  if (yystack->yyspaceLeft < YYHEADROOM)
-    yyexpandGLRStack (yystack]b4_pure_args[);
+yyaddDeferredAction (yyGLRStack* yystackp, yyGLRState* yystate,
+		     yyGLRState* rhs, yyRuleNum yyrule)
+{
+  yySemanticOption* yynewOption =
+    &yynewGLRStackItem (yystackp, yyfalse)->yyoption;
+  yynewOption->yystate = rhs;
+  yynewOption->yyrule = yyrule;
+  yynewOption->yynext = yystate->yysemantics.yyfirstVal;
+  yystate->yysemantics.yyfirstVal = yynewOption;
+
+  YY_RESERVE_GLRSTACK (yystackp);
 }
 
 				/* GLRStacks */
 
-/** Initialize SET to a singleton set containing an empty stack. */
+/** Initialize SET to a singleton set containing an empty stack.  */
 static yybool
 yyinitStateSet (yyGLRStateSet* yyset)
 {
@@ -963,46 +1131,50 @@ static void yyfreeStateSet (yyGLRStateSet* yyset)
 }
 
 /** Initialize STACK to a single empty stack, with total maximum
- *  capacity for all stacks of SIZE. */
+ *  capacity for all stacks of SIZE.  */
 static yybool
-yyinitGLRStack (yyGLRStack* yystack, size_t yysize)
+yyinitGLRStack (yyGLRStack* yystackp, size_t yysize)
 {
-  yystack->yyerrState = 0;
+  yystackp->yyerrState = 0;
   yynerrs = 0;
-  yystack->yyspaceLeft = yysize;
-  yystack->yynextFree = yystack->yyitems =
-    (yyGLRStackItem*) YYMALLOC (yysize * sizeof yystack->yynextFree[0]);
-  yystack->yysplitPoint = NULL;
-  yystack->yylastDeleted = NULL;
-  return yyinitStateSet (&yystack->yytops) && yystack->yyitems;
+  yystackp->yyspaceLeft = yysize;
+  yystackp->yyitems =
+    (yyGLRStackItem*) YYMALLOC (yysize * sizeof yystackp->yynextFree[0]);
+  if (!yystackp->yyitems)
+    return yyfalse;
+  yystackp->yynextFree = yystackp->yyitems;
+  yystackp->yysplitPoint = NULL;
+  yystackp->yylastDeleted = NULL;
+  return yyinitStateSet (&yystackp->yytops);
 }
 
-#define YYRELOC(YYFROMITEMS,YYTOITEMS,YYX,YYTYPE) \
+
+#if YYSTACKEXPANDABLE
+# define YYRELOC(YYFROMITEMS,YYTOITEMS,YYX,YYTYPE) \
   &((YYTOITEMS) - ((YYFROMITEMS) - (yyGLRStackItem*) (YYX)))->YYTYPE
 
 /** If STACK is expandable, extend it.  WARNING: Pointers into the
     stack from outside should be considered invalid after this call.
     We always expand when there are 1 or fewer items left AFTER an
     allocation, so that we can avoid having external pointers exist
-    across an allocation. */
+    across an allocation.  */
 static void
-yyexpandGLRStack (yyGLRStack* yystack]b4_pure_formals[)
+yyexpandGLRStack (yyGLRStack* yystackp)
 {
-#if YYSTACKEXPANDABLE
   yyGLRStackItem* yynewItems;
   yyGLRStackItem* yyp0, *yyp1;
   size_t yysize, yynewSize;
   size_t yyn;
-  yysize = yystack->yynextFree - yystack->yyitems;
+  yysize = yystackp->yynextFree - yystackp->yyitems;
   if (YYMAXDEPTH <= yysize)
-    yyStackOverflow (yystack]b4_pure_args[);
+    yyMemoryExhausted (yystackp);
   yynewSize = 2*yysize;
   if (YYMAXDEPTH < yynewSize)
     yynewSize = YYMAXDEPTH;
   yynewItems = (yyGLRStackItem*) YYMALLOC (yynewSize * sizeof yynewItems[0]);
   if (! yynewItems)
-    yyStackOverflow (yystack]b4_pure_args[);
-  for (yyp0 = yystack->yyitems, yyp1 = yynewItems, yyn = yysize;
+    yyMemoryExhausted (yystackp);
+  for (yyp0 = yystackp->yyitems, yyp1 = yynewItems, yyn = yysize;
        0 < yyn;
        yyn -= 1, yyp0 += 1, yyp1 += 1)
     {
@@ -1028,84 +1200,80 @@ yyexpandGLRStack (yyGLRStack* yystack]b4_pure_formals[)
 	    yyv1->yynext = YYRELOC (yyp0, yyp1, yyv0->yynext, yyoption);
 	}
     }
-  if (yystack->yysplitPoint != NULL)
-    yystack->yysplitPoint = YYRELOC (yystack->yyitems, yynewItems,
-				 yystack->yysplitPoint, yystate);
-
-  for (yyn = 0; yyn < yystack->yytops.yysize; yyn += 1)
-    if (yystack->yytops.yystates[yyn] != NULL)
-      yystack->yytops.yystates[yyn] =
-	YYRELOC (yystack->yyitems, yynewItems,
-		 yystack->yytops.yystates[yyn], yystate);
-  YYFREE (yystack->yyitems);
-  yystack->yyitems = yynewItems;
-  yystack->yynextFree = yynewItems + yysize;
-  yystack->yyspaceLeft = yynewSize - yysize;
-
-#else
-
-  yyStackOverflow (yystack]b4_pure_args[);
-#endif
+  if (yystackp->yysplitPoint != NULL)
+    yystackp->yysplitPoint = YYRELOC (yystackp->yyitems, yynewItems,
+				 yystackp->yysplitPoint, yystate);
+
+  for (yyn = 0; yyn < yystackp->yytops.yysize; yyn += 1)
+    if (yystackp->yytops.yystates[yyn] != NULL)
+      yystackp->yytops.yystates[yyn] =
+	YYRELOC (yystackp->yyitems, yynewItems,
+		 yystackp->yytops.yystates[yyn], yystate);
+  YYFREE (yystackp->yyitems);
+  yystackp->yyitems = yynewItems;
+  yystackp->yynextFree = yynewItems + yysize;
+  yystackp->yyspaceLeft = yynewSize - yysize;
 }
+#endif
 
 static void
-yyfreeGLRStack (yyGLRStack* yystack)
+yyfreeGLRStack (yyGLRStack* yystackp)
 {
-  YYFREE (yystack->yyitems);
-  yyfreeStateSet (&yystack->yytops);
+  YYFREE (yystackp->yyitems);
+  yyfreeStateSet (&yystackp->yytops);
 }
 
 /** Assuming that S is a GLRState somewhere on STACK, update the
  *  splitpoint of STACK, if needed, so that it is at least as deep as
- *  S. */
+ *  S.  */
 static inline void
-yyupdateSplit (yyGLRStack* yystack, yyGLRState* yys)
+yyupdateSplit (yyGLRStack* yystackp, yyGLRState* yys)
 {
-  if (yystack->yysplitPoint != NULL && yystack->yysplitPoint > yys)
-    yystack->yysplitPoint = yys;
+  if (yystackp->yysplitPoint != NULL && yystackp->yysplitPoint > yys)
+    yystackp->yysplitPoint = yys;
 }
 
-/** Invalidate stack #K in STACK. */
+/** Invalidate stack #K in STACK.  */
 static inline void
-yymarkStackDeleted (yyGLRStack* yystack, size_t yyk)
+yymarkStackDeleted (yyGLRStack* yystackp, size_t yyk)
 {
-  if (yystack->yytops.yystates[yyk] != NULL)
-    yystack->yylastDeleted = yystack->yytops.yystates[yyk];
-  yystack->yytops.yystates[yyk] = NULL;
+  if (yystackp->yytops.yystates[yyk] != NULL)
+    yystackp->yylastDeleted = yystackp->yytops.yystates[yyk];
+  yystackp->yytops.yystates[yyk] = NULL;
 }
 
 /** Undelete the last stack that was marked as deleted.  Can only be
     done once after a deletion, and only when all other stacks have
-    been deleted. */
+    been deleted.  */
 static void
-yyundeleteLastStack (yyGLRStack* yystack)
+yyundeleteLastStack (yyGLRStack* yystackp)
 {
-  if (yystack->yylastDeleted == NULL || yystack->yytops.yysize != 0)
+  if (yystackp->yylastDeleted == NULL || yystackp->yytops.yysize != 0)
     return;
-  yystack->yytops.yystates[0] = yystack->yylastDeleted;
-  yystack->yytops.yysize = 1;
+  yystackp->yytops.yystates[0] = yystackp->yylastDeleted;
+  yystackp->yytops.yysize = 1;
   YYDPRINTF ((stderr, "Restoring last deleted stack as stack #0.\n"));
-  yystack->yylastDeleted = NULL;
+  yystackp->yylastDeleted = NULL;
 }
 
 static inline void
-yyremoveDeletes (yyGLRStack* yystack)
+yyremoveDeletes (yyGLRStack* yystackp)
 {
   size_t yyi, yyj;
   yyi = yyj = 0;
-  while (yyj < yystack->yytops.yysize)
+  while (yyj < yystackp->yytops.yysize)
     {
-      if (yystack->yytops.yystates[yyi] == NULL)
+      if (yystackp->yytops.yystates[yyi] == NULL)
 	{
 	  if (yyi == yyj)
 	    {
 	      YYDPRINTF ((stderr, "Removing dead stacks.\n"));
 	    }
-	  yystack->yytops.yysize -= 1;
+	  yystackp->yytops.yysize -= 1;
 	}
       else
 	{
-	  yystack->yytops.yystates[yyj] = yystack->yytops.yystates[yyi];
+	  yystackp->yytops.yystates[yyj] = yystackp->yytops.yystates[yyi];
 	  if (yyj != yyi)
 	    {
 	      YYDPRINTF ((stderr, "Rename stack %lu -> %lu.\n",
@@ -1118,117 +1286,133 @@ yyremoveDeletes (yyGLRStack* yystack)
 }
 
 /** Shift to a new state on stack #K of STACK, corresponding to LR state
- * LRSTATE, at input position POSN, with (resolved) semantic value SVAL. */
+ * LRSTATE, at input position POSN, with (resolved) semantic value SVAL.  */
 static inline void
-yyglrShift (yyGLRStack* yystack, size_t yyk, yyStateNum yylrState,
+yyglrShift (yyGLRStack* yystackp, size_t yyk, yyStateNum yylrState,
 	    size_t yyposn,
-	    YYSTYPE yysval, YYLTYPE* yylocp]b4_user_formals[)
-{
-  yyGLRStackItem* yynewItem;
-
-  yynewItem = yystack->yynextFree;
-  yystack->yynextFree += 1;
-  yystack->yyspaceLeft -= 1;
-  yynewItem->yystate.yyisState = yytrue;
-  yynewItem->yystate.yylrState = yylrState;
-  yynewItem->yystate.yyposn = yyposn;
-  yynewItem->yystate.yyresolved = yytrue;
-  yynewItem->yystate.yypred = yystack->yytops.yystates[yyk];
-  yystack->yytops.yystates[yyk] = &yynewItem->yystate;
-  yynewItem->yystate.yysemantics.yysval = yysval;
-  yynewItem->yystate.yyloc = *yylocp;
-  if (yystack->yyspaceLeft < YYHEADROOM)
-    yyexpandGLRStack (yystack]b4_pure_args[);
+	    YYSTYPE* yyvalp, YYLTYPE* yylocp)
+{
+  yyGLRState* yynewState = &yynewGLRStackItem (yystackp, yytrue)->yystate;
+
+  yynewState->yylrState = yylrState;
+  yynewState->yyposn = yyposn;
+  yynewState->yyresolved = yytrue;
+  yynewState->yypred = yystackp->yytops.yystates[yyk];
+  yynewState->yysemantics.yysval = *yyvalp;
+  yynewState->yyloc = *yylocp;
+  yystackp->yytops.yystates[yyk] = yynewState;
+
+  YY_RESERVE_GLRSTACK (yystackp);
 }
 
 /** Shift stack #K of YYSTACK, to a new state corresponding to LR
  *  state YYLRSTATE, at input position YYPOSN, with the (unresolved)
- *  semantic value of YYRHS under the action for YYRULE. */
+ *  semantic value of YYRHS under the action for YYRULE.  */
 static inline void
-yyglrShiftDefer (yyGLRStack* yystack, size_t yyk, yyStateNum yylrState,
-		 size_t yyposn, yyGLRState* rhs, yyRuleNum yyrule]b4_pure_formals[)
-{
-  yyGLRStackItem* yynewItem;
-
-  yynewItem = yystack->yynextFree;
-  yynewItem->yystate.yyisState = yytrue;
-  yynewItem->yystate.yylrState = yylrState;
-  yynewItem->yystate.yyposn = yyposn;
-  yynewItem->yystate.yyresolved = yyfalse;
-  yynewItem->yystate.yypred = yystack->yytops.yystates[yyk];
-  yynewItem->yystate.yysemantics.yyfirstVal = NULL;
-  yystack->yytops.yystates[yyk] = &yynewItem->yystate;
-  yystack->yynextFree += 1;
-  yystack->yyspaceLeft -= 1;
-  yyaddDeferredAction (yystack, &yynewItem->yystate, rhs, yyrule]b4_pure_args[);
+yyglrShiftDefer (yyGLRStack* yystackp, size_t yyk, yyStateNum yylrState,
+		 size_t yyposn, yyGLRState* rhs, yyRuleNum yyrule)
+{
+  yyGLRState* yynewState = &yynewGLRStackItem (yystackp, yytrue)->yystate;
+
+  yynewState->yylrState = yylrState;
+  yynewState->yyposn = yyposn;
+  yynewState->yyresolved = yyfalse;
+  yynewState->yypred = yystackp->yytops.yystates[yyk];
+  yynewState->yysemantics.yyfirstVal = NULL;
+  yystackp->yytops.yystates[yyk] = yynewState;
+
+  /* Invokes YY_RESERVE_GLRSTACK.  */
+  yyaddDeferredAction (yystackp, yynewState, rhs, yyrule);
 }
 
 /** Pop the symbols consumed by reduction #RULE from the top of stack
  *  #K of STACK, and perform the appropriate semantic action on their
  *  semantic values.  Assumes that all ambiguities in semantic values
- *  have been previously resolved. Set *VALP to the resulting value,
+ *  have been previously resolved.  Set *VALP to the resulting value,
  *  and *LOCP to the computed location (if any).  Return value is as
- *  for userAction. */
+ *  for userAction.  */
 static inline YYRESULTTAG
-yydoAction (yyGLRStack* yystack, size_t yyk, yyRuleNum yyrule,
+yydoAction (yyGLRStack* yystackp, size_t yyk, yyRuleNum yyrule,
 	    YYSTYPE* yyvalp, YYLTYPE* yylocp]b4_user_formals[)
 {
   int yynrhs = yyrhsLength (yyrule);
 
-  if (yystack->yysplitPoint == NULL)
+  if (yystackp->yysplitPoint == NULL)
     {
-      /* Standard special case: single stack. */
-      yyGLRStackItem* rhs = (yyGLRStackItem*) yystack->yytops.yystates[yyk];
+      /* Standard special case: single stack.  */
+      yyGLRStackItem* rhs = (yyGLRStackItem*) yystackp->yytops.yystates[yyk];
       YYASSERT (yyk == 0);
-      yystack->yynextFree -= yynrhs;
-      yystack->yyspaceLeft += yynrhs;
-      yystack->yytops.yystates[0] = & yystack->yynextFree[-1].yystate;
+      yystackp->yynextFree -= yynrhs;
+      yystackp->yyspaceLeft += yynrhs;
+      yystackp->yytops.yystates[0] = & yystackp->yynextFree[-1].yystate;
       return yyuserAction (yyrule, yynrhs, rhs,
-			   yyvalp, yylocp, yystack]b4_user_args[);
+			   yyvalp, yylocp, yystackp]b4_user_args[);
     }
   else
     {
+      /* At present, doAction is never called in nondeterministic
+       * mode, so this branch is never taken.  It is here in
+       * anticipation of a future feature that will allow immediate
+       * evaluation of selected actions in nondeterministic mode.  */
       int yyi;
       yyGLRState* yys;
       yyGLRStackItem yyrhsVals[YYMAXRHS + YYMAXLEFT + 1];
       yys = yyrhsVals[YYMAXRHS + YYMAXLEFT].yystate.yypred
-	= yystack->yytops.yystates[yyk];
+	= yystackp->yytops.yystates[yyk];]b4_location_if([[
+      if (yynrhs == 0)
+	/* Set default location.  */
+	yyrhsVals[YYMAXRHS + YYMAXLEFT - 1].yystate.yyloc = yys->yyloc;]])[
       for (yyi = 0; yyi < yynrhs; yyi += 1)
 	{
 	  yys = yys->yypred;
 	  YYASSERT (yys);
 	}
-      yyupdateSplit (yystack, yys);
-      yystack->yytops.yystates[yyk] = yys;
+      yyupdateSplit (yystackp, yys);
+      yystackp->yytops.yystates[yyk] = yys;
       return yyuserAction (yyrule, yynrhs, yyrhsVals + YYMAXRHS + YYMAXLEFT - 1,
-			   yyvalp, yylocp, yystack]b4_user_args[);
+			   yyvalp, yylocp, yystackp]b4_user_args[);
     }
 }
 
 #if !YYDEBUG
-# define YY_REDUCE_PRINT(K, Rule)
+# define YY_REDUCE_PRINT(Args)
 #else
-# define YY_REDUCE_PRINT(K, Rule)	\
+# define YY_REDUCE_PRINT(Args)		\
 do {					\
   if (yydebug)				\
-    yy_reduce_print (K, Rule);		\
-} while (0)
+    yy_reduce_print Args;		\
+} while (YYID (0))
 
 /*----------------------------------------------------------.
 | Report that the RULE is going to be reduced on stack #K.  |
 `----------------------------------------------------------*/
 
-static inline void
-yy_reduce_print (size_t yyk, yyRuleNum yyrule)
+/*ARGSUSED*/ static inline void
+yy_reduce_print (yyGLRStack* yystackp, size_t yyk, yyRuleNum yyrule,
+		 YYSTYPE* yyvalp, YYLTYPE* yylocp]b4_user_formals[)
 {
+  int yynrhs = yyrhsLength (yyrule);
+  yybool yynormal __attribute__ ((__unused__)) =
+    (yystackp->yysplitPoint == NULL);
+  yyGLRStackItem* yyvsp = (yyGLRStackItem*) yystackp->yytops.yystates[yyk];
+  int yylow = 1;
   int yyi;
-  YYFPRINTF (stderr, "Reducing stack %lu by rule %d (line %lu), ",
+  YYUSE (yyvalp);
+  YYUSE (yylocp);
+]b4_parse_param_use[]dnl
+[  YYFPRINTF (stderr, "Reducing stack %lu by rule %d (line %lu):\n",
 	     (unsigned long int) yyk, yyrule - 1,
 	     (unsigned long int) yyrline[yyrule]);
-  /* Print the symbols being reduced, and their result.  */
-  for (yyi = yyprhs[yyrule]; 0 <= yyrhs[yyi]; yyi++)
-    YYFPRINTF (stderr, "%s ", yytokenName (yyrhs[yyi]));
-  YYFPRINTF (stderr, "-> %s\n", yytokenName (yyr1[yyrule]));
+  /* The symbols being reduced.  */
+  for (yyi = 0; yyi < yynrhs; yyi++)
+    {
+      fprintf (stderr, "   $%d = ", yyi + 1);
+      yy_symbol_print (stderr, yyrhs[yyprhs[yyrule] + yyi],
+		       &]b4_rhs_value(yynrhs, yyi + 1)[
+		       ]b4_location_if([, &]b4_rhs_location(yynrhs, yyi + 1))[]dnl
+		       b4_user_args[);
+      fprintf (stderr, "\n");
+    }
 }
 #endif
 
@@ -1240,56 +1424,58 @@ yy_reduce_print (size_t yyk, yyRuleNum yyrule)
  *  the new state.  If the new state would have an identical input
  *  position, LR state, and predecessor to an existing state on the stack,
  *  it is identified with that existing state, eliminating stack #K from
- *  the STACK. In this case, the (necessarily deferred) semantic value is
+ *  the STACK.  In this case, the (necessarily deferred) semantic value is
  *  added to the options for the existing state's semantic value.
  */
 static inline YYRESULTTAG
-yyglrReduce (yyGLRStack* yystack, size_t yyk, yyRuleNum yyrule,
-             yybool yyforceEval]b4_pure_formals[)
+yyglrReduce (yyGLRStack* yystackp, size_t yyk, yyRuleNum yyrule,
+	     yybool yyforceEval]b4_user_formals[)
 {
-  size_t yyposn = yystack->yytops.yystates[yyk]->yyposn;
+  size_t yyposn = yystackp->yytops.yystates[yyk]->yyposn;
 
-  if (yyforceEval || yystack->yysplitPoint == NULL)
+  if (yyforceEval || yystackp->yysplitPoint == NULL)
     {
       YYSTYPE yysval;
       YYLTYPE yyloc;
 
-      YY_REDUCE_PRINT (yyk, yyrule);
-      YYCHK (yydoAction (yystack, yyk, yyrule, &yysval, &yyloc]b4_user_args[));
-      yyglrShift (yystack, yyk,
-		  yyLRgotoState (yystack->yytops.yystates[yyk]->yylrState,
+      YY_REDUCE_PRINT ((yystackp, yyk, yyrule, &yysval, &yyloc]b4_user_args[));
+      YYCHK (yydoAction (yystackp, yyk, yyrule, &yysval,
+			 &yyloc]b4_user_args[));
+      YY_SYMBOL_PRINT ("-> $$ =", yyr1[yyrule], &yysval, &yyloc);
+      yyglrShift (yystackp, yyk,
+		  yyLRgotoState (yystackp->yytops.yystates[yyk]->yylrState,
 				 yylhsNonterm (yyrule)),
-		  yyposn, yysval, &yyloc]b4_user_args[);
+		  yyposn, &yysval, &yyloc);
     }
   else
     {
       size_t yyi;
       int yyn;
-      yyGLRState* yys, *yys0 = yystack->yytops.yystates[yyk];
+      yyGLRState* yys, *yys0 = yystackp->yytops.yystates[yyk];
       yyStateNum yynewLRState;
 
-      for (yys = yystack->yytops.yystates[yyk], yyn = yyrhsLength (yyrule);
+      for (yys = yystackp->yytops.yystates[yyk], yyn = yyrhsLength (yyrule);
 	   0 < yyn; yyn -= 1)
 	{
 	  yys = yys->yypred;
 	  YYASSERT (yys);
 	}
-      yyupdateSplit (yystack, yys);
+      yyupdateSplit (yystackp, yys);
       yynewLRState = yyLRgotoState (yys->yylrState, yylhsNonterm (yyrule));
       YYDPRINTF ((stderr,
-		  "Reduced stack %lu by rule #%d; action deferred. Now in state %d.\n",
+		  "Reduced stack %lu by rule #%d; action deferred.  Now in state %d.\n",
 		  (unsigned long int) yyk, yyrule - 1, yynewLRState));
-      for (yyi = 0; yyi < yystack->yytops.yysize; yyi += 1)
-	if (yyi != yyk && yystack->yytops.yystates[yyi] != NULL)
+      for (yyi = 0; yyi < yystackp->yytops.yysize; yyi += 1)
+	if (yyi != yyk && yystackp->yytops.yystates[yyi] != NULL)
 	  {
-	    yyGLRState* yyp, *yysplit = yystack->yysplitPoint;
-	    yyp = yystack->yytops.yystates[yyi];
+	    yyGLRState* yyp, *yysplit = yystackp->yysplitPoint;
+	    yyp = yystackp->yytops.yystates[yyi];
 	    while (yyp != yys && yyp != yysplit && yyp->yyposn >= yyposn)
 	      {
 		if (yyp->yylrState == yynewLRState && yyp->yypred == yys)
 		  {
-		    yyaddDeferredAction (yystack, yyp, yys0, yyrule]b4_pure_args[);
-		    yymarkStackDeleted (yystack, yyk);
+		    yyaddDeferredAction (yystackp, yyp, yys0, yyrule);
+		    yymarkStackDeleted (yystackp, yyk);
 		    YYDPRINTF ((stderr, "Merging stack %lu into stack %lu.\n",
 				(unsigned long int) yyk,
 				(unsigned long int) yyi));
@@ -1298,41 +1484,41 @@ yyglrReduce (yyGLRStack* yystack, size_t yyk, yyRuleNum yyrule,
 		yyp = yyp->yypred;
 	      }
 	  }
-      yystack->yytops.yystates[yyk] = yys;
-      yyglrShiftDefer (yystack, yyk, yynewLRState, yyposn, yys0, yyrule]b4_pure_args[);
+      yystackp->yytops.yystates[yyk] = yys;
+      yyglrShiftDefer (yystackp, yyk, yynewLRState, yyposn, yys0, yyrule);
     }
   return yyok;
 }
 
 static size_t
-yysplitStack (yyGLRStack* yystack, size_t yyk]b4_pure_formals[)
+yysplitStack (yyGLRStack* yystackp, size_t yyk)
 {
-  if (yystack->yysplitPoint == NULL)
+  if (yystackp->yysplitPoint == NULL)
     {
       YYASSERT (yyk == 0);
-      yystack->yysplitPoint = yystack->yytops.yystates[yyk];
+      yystackp->yysplitPoint = yystackp->yytops.yystates[yyk];
     }
-  if (yystack->yytops.yysize >= yystack->yytops.yycapacity)
+  if (yystackp->yytops.yysize >= yystackp->yytops.yycapacity)
     {
       yyGLRState** yynewStates;
-      if (! ((yystack->yytops.yycapacity
+      if (! ((yystackp->yytops.yycapacity
 	      <= (YYSIZEMAX / (2 * sizeof yynewStates[0])))
 	     && (yynewStates =
-		 (yyGLRState**) YYREALLOC (yystack->yytops.yystates,
-					   ((yystack->yytops.yycapacity *= 2)
+		 (yyGLRState**) YYREALLOC (yystackp->yytops.yystates,
+					   ((yystackp->yytops.yycapacity *= 2)
 					    * sizeof yynewStates[0])))))
-	yyStackOverflow (yystack]b4_pure_args[);
-      yystack->yytops.yystates = yynewStates;
+	yyMemoryExhausted (yystackp);
+      yystackp->yytops.yystates = yynewStates;
     }
-  yystack->yytops.yystates[yystack->yytops.yysize]
-    = yystack->yytops.yystates[yyk];
-  yystack->yytops.yysize += 1;
-  return yystack->yytops.yysize-1;
+  yystackp->yytops.yystates[yystackp->yytops.yysize]
+    = yystackp->yytops.yystates[yyk];
+  yystackp->yytops.yysize += 1;
+  return yystackp->yytops.yysize-1;
 }
 
 /** True iff Y0 and Y1 represent identical options at the top level.
  *  That is, they represent the same rule applied to RHS symbols
- *  that produce the same terminal symbols. */
+ *  that produce the same terminal symbols.  */
 static yybool
 yyidenticalOptions (yySemanticOption* yyy0, yySemanticOption* yyy1)
 {
@@ -1353,7 +1539,7 @@ yyidenticalOptions (yySemanticOption* yyy0, yySemanticOption* yyy1)
 }
 
 /** Assuming identicalOptions (Y0,Y1), destructively merge the
- *  alternative semantic values for the RHS-symbols of Y1 and Y0. */
+ *  alternative semantic values for the RHS-symbols of Y1 and Y0.  */
 static void
 yymergeOptionSets (yySemanticOption* yyy0, yySemanticOption* yyy1)
 {
@@ -1382,7 +1568,7 @@ yymergeOptionSets (yySemanticOption* yyy0, yySemanticOption* yyy1)
 	  yySemanticOption* yyz1;
 	  yyz0p = &yys0->yysemantics.yyfirstVal;
 	  yyz1 = yys1->yysemantics.yyfirstVal;
-	  while (yytrue)
+	  while (YYID (yytrue))
 	    {
 	      if (yyz1 == *yyz0p || yyz1 == NULL)
 		break;
@@ -1407,7 +1593,7 @@ yymergeOptionSets (yySemanticOption* yyy0, yySemanticOption* yyy1)
 
 /** Y0 and Y1 represent two possible actions to take in a given
  *  parsing state; return 0 if no combination is possible,
- *  1 if user-mergeable, 2 if Y0 is preferred, 3 if Y1 is preferred. */
+ *  1 if user-mergeable, 2 if Y0 is preferred, 3 if Y1 is preferred.  */
 static int
 yypreference (yySemanticOption* y0, yySemanticOption* y1)
 {
@@ -1431,22 +1617,23 @@ yypreference (yySemanticOption* y0, yySemanticOption* y1)
 }
 
 static YYRESULTTAG yyresolveValue (yySemanticOption* yyoptionList,
-				   yyGLRStack* yystack, YYSTYPE* yyvalp,
+				   yyGLRStack* yystackp, YYSTYPE* yyvalp,
 				   YYLTYPE* yylocp]b4_user_formals[);
 
 static YYRESULTTAG
-yyresolveStates (yyGLRState* yys, int yyn, yyGLRStack* yystack]b4_user_formals[)
+yyresolveStates (yyGLRState* yys, int yyn,
+		 yyGLRStack* yystackp]b4_user_formals[)
 {
   YYRESULTTAG yyflag;
   if (0 < yyn)
     {
       YYASSERT (yys->yypred);
-      yyflag = yyresolveStates (yys->yypred, yyn-1, yystack]b4_user_args[);
+      yyflag = yyresolveStates (yys->yypred, yyn-1, yystackp]b4_user_args[);
       if (yyflag != yyok)
 	return yyflag;
       if (! yys->yyresolved)
 	{
-	  yyflag = yyresolveValue (yys->yysemantics.yyfirstVal, yystack,
+	  yyflag = yyresolveValue (yys->yysemantics.yyfirstVal, yystackp,
 				   &yys->yysemantics.yysval, &yys->yyloc
 				  ]b4_user_args[);
 	  if (yyflag != yyok)
@@ -1458,18 +1645,21 @@ yyresolveStates (yyGLRState* yys, int yyn, yyGLRStack* yystack]b4_user_formals[)
 }
 
 static YYRESULTTAG
-yyresolveAction (yySemanticOption* yyopt, yyGLRStack* yystack,
-	         YYSTYPE* yyvalp, YYLTYPE* yylocp]b4_user_formals[)
+yyresolveAction (yySemanticOption* yyopt, yyGLRStack* yystackp,
+		 YYSTYPE* yyvalp, YYLTYPE* yylocp]b4_user_formals[)
 {
   yyGLRStackItem yyrhsVals[YYMAXRHS + YYMAXLEFT + 1];
   int yynrhs;
 
   yynrhs = yyrhsLength (yyopt->yyrule);
-  YYCHK (yyresolveStates (yyopt->yystate, yynrhs, yystack]b4_user_args[));
-  yyrhsVals[YYMAXRHS + YYMAXLEFT].yystate.yypred = yyopt->yystate;
+  YYCHK (yyresolveStates (yyopt->yystate, yynrhs, yystackp]b4_user_args[));
+  yyrhsVals[YYMAXRHS + YYMAXLEFT].yystate.yypred = yyopt->yystate;]b4_location_if([[
+  if (yynrhs == 0)
+    /* Set default location.  */
+    yyrhsVals[YYMAXRHS + YYMAXLEFT - 1].yystate.yyloc = yyopt->yystate->yyloc;]])[
   return yyuserAction (yyopt->yyrule, yynrhs,
 		       yyrhsVals + YYMAXRHS + YYMAXLEFT - 1,
-		       yyvalp, yylocp, yystack]b4_user_args[);
+		       yyvalp, yylocp, yystackp]b4_user_args[);
 }
 
 #if YYDEBUG
@@ -1520,13 +1710,15 @@ yyreportTree (yySemanticOption* yyx, int yyindent)
 }
 #endif
 
+static void yyreportAmbiguity (yySemanticOption* yyx0, yySemanticOption* yyx1,
+			       yyGLRStack* yystackp]b4_pure_formals[)
+  __attribute__ ((__noreturn__));
 static void
 yyreportAmbiguity (yySemanticOption* yyx0, yySemanticOption* yyx1,
-		   yyGLRStack* yystack]b4_pure_formals[)
+		   yyGLRStack* yystackp]b4_pure_formals[)
 {
-  /* `Unused' warnings.  */
-  (void) yyx0;
-  (void) yyx1;
+  YYUSE (yyx0);
+  YYUSE (yyx1);
 
 #if YYDEBUG
   YYFPRINTF (stderr, "Ambiguity detected.\n");
@@ -1536,125 +1728,139 @@ yyreportAmbiguity (yySemanticOption* yyx0, yySemanticOption* yyx1,
   yyreportTree (yyx1, 2);
   YYFPRINTF (stderr, "\n");
 #endif
-  yyFail (yystack][]b4_pure_args[, YY_("ambiguity detected"));
+  yyFail (yystackp][]b4_pure_args[, YY_("syntax is ambiguous"));
 }
 
 
 /** Resolve the ambiguity represented by OPTIONLIST, perform the indicated
- *  actions, and return the result. */
+ *  actions, and return the result.  */
 static YYRESULTTAG
-yyresolveValue (yySemanticOption* yyoptionList, yyGLRStack* yystack,
+yyresolveValue (yySemanticOption* yyoptionList, yyGLRStack* yystackp,
 		YYSTYPE* yyvalp, YYLTYPE* yylocp]b4_user_formals[)
 {
   yySemanticOption* yybest;
-  yySemanticOption* yyp;
+  yySemanticOption** yypp;
   yybool yymerge;
 
   yybest = yyoptionList;
   yymerge = yyfalse;
-  for (yyp = yyoptionList->yynext; yyp != NULL; yyp = yyp->yynext)
+  for (yypp = &yyoptionList->yynext; *yypp != NULL; )
     {
+      yySemanticOption* yyp = *yypp;
+
       if (yyidenticalOptions (yybest, yyp))
-	yymergeOptionSets (yybest, yyp);
+	{
+	  yymergeOptionSets (yybest, yyp);
+	  *yypp = yyp->yynext;
+	}
       else
-	switch (yypreference (yybest, yyp))
-	  {
-	  case 0:
-	    yyreportAmbiguity (yybest, yyp, yystack]b4_pure_args[);
-	    break;
-	  case 1:
-	    yymerge = yytrue;
-	    break;
-	  case 2:
-	    break;
-	  case 3:
-	    yybest = yyp;
-	    yymerge = yyfalse;
-	    break;
-	  }
+	{
+	  switch (yypreference (yybest, yyp))
+	    {
+	    case 0:
+	      yyreportAmbiguity (yybest, yyp, yystackp]b4_pure_args[);
+	      break;
+	    case 1:
+	      yymerge = yytrue;
+	      break;
+	    case 2:
+	      break;
+	    case 3:
+	      yybest = yyp;
+	      yymerge = yyfalse;
+	      break;
+	    default:
+	      /* This cannot happen so it is not worth a YYASSERT (yyfalse),
+		 but some compilers complain if the default case is
+		 omitted.  */
+	      break;
+	    }
+	  yypp = &yyp->yynext;
+	}
     }
 
   if (yymerge)
     {
+      yySemanticOption* yyp;
       int yyprec = yydprec[yybest->yyrule];
-      YYCHK (yyresolveAction (yybest, yystack, yyvalp, yylocp]b4_user_args[));
+      YYCHK (yyresolveAction (yybest, yystackp, yyvalp, yylocp]b4_user_args[));
       for (yyp = yybest->yynext; yyp != NULL; yyp = yyp->yynext)
 	{
 	  if (yyprec == yydprec[yyp->yyrule])
 	    {
 	      YYSTYPE yyval1;
 	      YYLTYPE yydummy;
-	      YYCHK (yyresolveAction (yyp, yystack, &yyval1, &yydummy]b4_user_args[));
+	      YYCHK (yyresolveAction (yyp, yystackp, &yyval1,
+				      &yydummy]b4_user_args[));
 	      yyuserMerge (yymerger[yyp->yyrule], yyvalp, &yyval1);
 	    }
 	}
       return yyok;
     }
   else
-    return yyresolveAction (yybest, yystack, yyvalp, yylocp]b4_user_args[);
+    return yyresolveAction (yybest, yystackp, yyvalp, yylocp]b4_user_args[);
 }
 
 static YYRESULTTAG
-yyresolveStack (yyGLRStack* yystack]b4_user_formals[)
+yyresolveStack (yyGLRStack* yystackp]b4_user_formals[)
 {
-  if (yystack->yysplitPoint != NULL)
+  if (yystackp->yysplitPoint != NULL)
     {
       yyGLRState* yys;
       int yyn;
 
-      for (yyn = 0, yys = yystack->yytops.yystates[0];
-	   yys != yystack->yysplitPoint;
+      for (yyn = 0, yys = yystackp->yytops.yystates[0];
+	   yys != yystackp->yysplitPoint;
 	   yys = yys->yypred, yyn += 1)
 	continue;
-      YYCHK (yyresolveStates (yystack->yytops.yystates[0], yyn, yystack
+      YYCHK (yyresolveStates (yystackp->yytops.yystates[0], yyn, yystackp
 			     ]b4_user_args[));
     }
   return yyok;
 }
 
 static void
-yycompressStack (yyGLRStack* yystack)
+yycompressStack (yyGLRStack* yystackp)
 {
   yyGLRState* yyp, *yyq, *yyr;
 
-  if (yystack->yytops.yysize != 1 || yystack->yysplitPoint == NULL)
+  if (yystackp->yytops.yysize != 1 || yystackp->yysplitPoint == NULL)
     return;
 
-  for (yyp = yystack->yytops.yystates[0], yyq = yyp->yypred, yyr = NULL;
-       yyp != yystack->yysplitPoint;
+  for (yyp = yystackp->yytops.yystates[0], yyq = yyp->yypred, yyr = NULL;
+       yyp != yystackp->yysplitPoint;
        yyr = yyp, yyp = yyq, yyq = yyp->yypred)
     yyp->yypred = yyr;
 
-  yystack->yyspaceLeft += yystack->yynextFree - yystack->yyitems;
-  yystack->yynextFree = ((yyGLRStackItem*) yystack->yysplitPoint) + 1;
-  yystack->yyspaceLeft -= yystack->yynextFree - yystack->yyitems;
-  yystack->yysplitPoint = NULL;
-  yystack->yylastDeleted = NULL;
+  yystackp->yyspaceLeft += yystackp->yynextFree - yystackp->yyitems;
+  yystackp->yynextFree = ((yyGLRStackItem*) yystackp->yysplitPoint) + 1;
+  yystackp->yyspaceLeft -= yystackp->yynextFree - yystackp->yyitems;
+  yystackp->yysplitPoint = NULL;
+  yystackp->yylastDeleted = NULL;
 
   while (yyr != NULL)
     {
-      yystack->yynextFree->yystate = *yyr;
+      yystackp->yynextFree->yystate = *yyr;
       yyr = yyr->yypred;
-      yystack->yynextFree->yystate.yypred = & yystack->yynextFree[-1].yystate;
-      yystack->yytops.yystates[0] = &yystack->yynextFree->yystate;
-      yystack->yynextFree += 1;
-      yystack->yyspaceLeft -= 1;
+      yystackp->yynextFree->yystate.yypred = &yystackp->yynextFree[-1].yystate;
+      yystackp->yytops.yystates[0] = &yystackp->yynextFree->yystate;
+      yystackp->yynextFree += 1;
+      yystackp->yyspaceLeft -= 1;
     }
 }
 
 static YYRESULTTAG
-yyprocessOneStack (yyGLRStack* yystack, size_t yyk,
-	           size_t yyposn, YYSTYPE* yylvalp, YYLTYPE* yyllocp
-		  ]b4_pure_formals[)
+yyprocessOneStack (yyGLRStack* yystackp, size_t yyk,
+                  size_t yyposn]b4_pure_formals[)
 {
   int yyaction;
   const short int* yyconflicts;
   yyRuleNum yyrule;
-  yySymbol* const yytokenp = yystack->yytokenp;
+  yySymbol* const yytokenp = yystackp->yytokenp;
 
-  while (yystack->yytops.yystates[yyk] != NULL)
+  while (yystackp->yytops.yystates[yyk] != NULL)
     {
-      yyStateNum yystate = yystack->yytops.yystates[yyk]->yylrState;
+      yyStateNum yystate = yystackp->yytops.yystates[yyk]->yylrState;
       YYDPRINTF ((stderr, "Stack %lu Entering state %d\n",
 		  (unsigned long int) yyk, yystate));
 
@@ -1667,10 +1873,10 @@ yyprocessOneStack (yyGLRStack* yystack, size_t yyk,
 	    {
 	      YYDPRINTF ((stderr, "Stack %lu dies.\n",
 			  (unsigned long int) yyk));
-	      yymarkStackDeleted (yystack, yyk);
+	      yymarkStackDeleted (yystackp, yyk);
 	      return yyok;
 	    }
-	  YYCHK (yyglrReduce (yystack, yyk, yyrule, yyfalse]b4_lpure_args[));
+	  YYCHK (yyglrReduce (yystackp, yyk, yyrule, yyfalse]b4_user_args[));
 	}
       else
 	{
@@ -1679,65 +1885,52 @@ yyprocessOneStack (yyGLRStack* yystack, size_t yyk,
 	      YYDPRINTF ((stderr, "Reading a token: "));
 	      yychar = YYLEX;
 	      *yytokenp = YYTRANSLATE (yychar);
-	      YY_SYMBOL_PRINT ("Next token is", *yytokenp, yylvalp, yyllocp);
-	      YYDPRINTF ((stderr, "\n"));
+             YY_SYMBOL_PRINT ("Next token is", *yytokenp, &yylval, &yylloc);
 	    }
 	  yygetLRActions (yystate, *yytokenp, &yyaction, &yyconflicts);
 
 	  while (*yyconflicts != 0)
 	    {
-	      size_t yynewStack = yysplitStack (yystack, yyk]b4_pure_args[);
+	      size_t yynewStack = yysplitStack (yystackp, yyk);
 	      YYDPRINTF ((stderr, "Splitting off stack %lu from %lu.\n",
 			  (unsigned long int) yynewStack,
 			  (unsigned long int) yyk));
-	      YYCHK (yyglrReduce (yystack, yynewStack,
-				  *yyconflicts, yyfalse]b4_lpure_args[));
-	      YYCHK (yyprocessOneStack (yystack, yynewStack, yyposn,
-					yylvalp, yyllocp]b4_pure_args[));
+	      YYCHK (yyglrReduce (yystackp, yynewStack,
+				  *yyconflicts, yyfalse]b4_user_args[));
+             YYCHK (yyprocessOneStack (yystackp, yynewStack,
+                                       yyposn]b4_pure_args[));
 	      yyconflicts += 1;
 	    }
 
 	  if (yyisShiftAction (yyaction))
-	    {
-	      YYDPRINTF ((stderr, "On stack %lu, ", (unsigned long int) yyk));
-	      YY_SYMBOL_PRINT ("shifting", *yytokenp, yylvalp, yyllocp);
-	      yyglrShift (yystack, yyk, yyaction, yyposn+1,
-			  *yylvalp, yyllocp]b4_user_args[);
-	      YYDPRINTF ((stderr, ", now in state #%d\n",
-			  yystack->yytops.yystates[yyk]->yylrState));
-	      break;
-	    }
+	    break;
 	  else if (yyisErrorAction (yyaction))
 	    {
 	      YYDPRINTF ((stderr, "Stack %lu dies.\n",
 			  (unsigned long int) yyk));
-	      yymarkStackDeleted (yystack, yyk);
+	      yymarkStackDeleted (yystackp, yyk);
 	      break;
 	    }
 	  else
-	    YYCHK (yyglrReduce (yystack, yyk, -yyaction, yyfalse]b4_lpure_args[));
+           YYCHK (yyglrReduce (yystackp, yyk, -yyaction,
+                               yyfalse]b4_user_args[));
 	}
     }
   return yyok;
 }
 
-static void
-yyreportSyntaxError (yyGLRStack* yystack,
-		     YYSTYPE* yylvalp, YYLTYPE* yyllocp]b4_user_formals[)
+/*ARGSUSED*/ static void
+yyreportSyntaxError (yyGLRStack* yystackp]b4_user_formals[)
 {
-  /* `Unused' warnings. */
-  (void) yylvalp;
-  (void) yyllocp;
-
-  if (yystack->yyerrState == 0)
+  if (yystackp->yyerrState == 0)
     {
 #if YYERROR_VERBOSE
-      yySymbol* const yytokenp = yystack->yytokenp;
+      yySymbol* const yytokenp = yystackp->yytokenp;
       int yyn;
-      yyn = yypact[yystack->yytops.yystates[0]->yylrState];
+      yyn = yypact[yystackp->yytops.yystates[0]->yylrState];
       if (YYPACT_NINF < yyn && yyn < YYLAST)
 	{
-	  size_t yysize0 = strlen (yytokenName (*yytokenp));
+	  size_t yysize0 = yytnamerr (NULL, yytokenName (*yytokenp));
 	  size_t yysize = yysize0;
 	  size_t yysize1;
 	  yybool yysize_overflow = yyfalse;
@@ -1779,7 +1972,7 @@ yyreportSyntaxError (yyGLRStack* yystack,
 		    break;
 		  }
 		yyarg[yycount++] = yytokenName (yyx);
-		yysize1 = yysize + strlen (yytokenName (yyx));
+		yysize1 = yysize + yytnamerr (NULL, yytokenName (yyx));
 		yysize_overflow |= yysize1 < yysize;
 		yysize = yysize1;
 		yyfmt = yystpcpy (yyfmt, yyprefix);
@@ -1802,7 +1995,7 @@ yyreportSyntaxError (yyGLRStack* yystack,
 		{
 		  if (*yyp == '%' && yyf[1] == 's' && yyi < yycount)
 		    {
-		      yyp = yystpcpy (yyp, yyarg[yyi++]);
+		      yyp += yytnamerr (yyp, yyarg[yyi++]);
 		      yyf += 2;
 		    }
 		  else
@@ -1815,7 +2008,10 @@ yyreportSyntaxError (yyGLRStack* yystack,
 	      YYFREE (yymsg);
 	    }
 	  else
-	    yyerror (]b4_lyyerror_args[YY_("syntax error; also memory exhausted"));
+	    {
+	      yyerror (]b4_lyyerror_args[YY_("syntax error"));
+	      yyMemoryExhausted (yystackp);
+	    }
 	}
       else
 #endif /* YYERROR_VERBOSE */
@@ -1824,64 +2020,46 @@ yyreportSyntaxError (yyGLRStack* yystack,
     }
 }
 
-/* Recover from a syntax error on YYSTACK, assuming that YYTOKENP,
-   YYLVALP, and YYLLOCP point to the syntactic category, semantic
-   value, and location of the look-ahead.  */
-static void
-yyrecoverSyntaxError (yyGLRStack* yystack,
-		      YYSTYPE* yylvalp,
-		      YYLTYPE* YYOPTIONAL_LOC (yyllocp)
-		      ]b4_user_formals[)
+/* Recover from a syntax error on *YYSTACKP, assuming that *YYSTACKP->YYTOKENP,
+   yylval, and yylloc are the syntactic category, semantic value, and location
+   of the look-ahead.  */
+/*ARGSUSED*/ static void
+yyrecoverSyntaxError (yyGLRStack* yystackp]b4_user_formals[)
 {
-  yySymbol* const yytokenp = yystack->yytokenp;
+  yySymbol* const yytokenp = yystackp->yytokenp;
   size_t yyk;
   int yyj;
 
-  if (yystack->yyerrState == 3)
+  if (yystackp->yyerrState == 3)
     /* We just shifted the error token and (perhaps) took some
        reductions.  Skip tokens until we can proceed.  */
-    while (yytrue)
+    while (YYID (yytrue))
       {
 	if (*yytokenp == YYEOF)
-	  {
-	    /* Now pop stack until empty and fail. */
-	    while (yystack->yytops.yystates[0] != NULL)
-	      {
-		yyGLRState *yys = yystack->yytops.yystates[0];
-]b4_location_if([[		yystack->yyerror_range[1].yystate.yyloc = yys->yyloc;]])[
-		yydestruct ("Error: popping",
-                            yystos[yys->yylrState],
-			    &yys->yysemantics.yysval]b4_location_if([, &yys->yyloc])[);
-		yystack->yytops.yystates[0] = yys->yypred;
-		yystack->yynextFree -= 1;
-		yystack->yyspaceLeft += 1;
-	      }
-	    yyFail (yystack][]b4_lpure_args[, NULL);
-	  }
+	  yyFail (yystackp][]b4_lpure_args[, NULL);
 	if (*yytokenp != YYEMPTY)
 	  {]b4_location_if([[
 	    /* We throw away the lookahead, but the error range
-	       of the shifted error token must take it into account. */
-	    yyGLRState *yys = yystack->yytops.yystates[0];
+	       of the shifted error token must take it into account.  */
+	    yyGLRState *yys = yystackp->yytops.yystates[0];
 	    yyGLRStackItem yyerror_range[3];
 	    yyerror_range[1].yystate.yyloc = yys->yyloc;
-	    yyerror_range[2].yystate.yyloc = *yyllocp;
+           yyerror_range[2].yystate.yyloc = yylloc;
 	    YYLLOC_DEFAULT (yys->yyloc, yyerror_range, 2);]])[
 	    yydestruct ("Error: discarding",
-			*yytokenp, yylvalp]b4_location_if([, yyllocp])[);
+                       *yytokenp, &yylval]b4_location_if([, &yylloc])[]b4_user_args[);
 	  }
 	YYDPRINTF ((stderr, "Reading a token: "));
 	yychar = YYLEX;
 	*yytokenp = YYTRANSLATE (yychar);
-	YY_SYMBOL_PRINT ("Next token is", *yytokenp, yylvalp, yyllocp);
-	YYDPRINTF ((stderr, "\n"));
-	yyj = yypact[yystack->yytops.yystates[0]->yylrState];
+       YY_SYMBOL_PRINT ("Next token is", *yytokenp, &yylval, &yylloc);
+	yyj = yypact[yystackp->yytops.yystates[0]->yylrState];
 	if (yyis_pact_ninf (yyj))
 	  return;
 	yyj += *yytokenp;
 	if (yyj < 0 || YYLAST < yyj || yycheck[yyj] != *yytokenp)
 	  {
-	    if (yydefact[yystack->yytops.yystates[0]->yylrState] != 0)
+	    if (yydefact[yystackp->yytops.yystates[0]->yylrState] != 0)
 	      return;
 	  }
 	else if (yytable[yyj] != 0 && ! yyis_table_ninf (yytable[yyj]))
@@ -1889,21 +2067,21 @@ yyrecoverSyntaxError (yyGLRStack* yystack,
       }
 
   /* Reduce to one stack.  */
-  for (yyk = 0; yyk < yystack->yytops.yysize; yyk += 1)
-    if (yystack->yytops.yystates[yyk] != NULL)
+  for (yyk = 0; yyk < yystackp->yytops.yysize; yyk += 1)
+    if (yystackp->yytops.yystates[yyk] != NULL)
       break;
-  if (yyk >= yystack->yytops.yysize)
-    yyFail (yystack][]b4_lpure_args[, NULL);
-  for (yyk += 1; yyk < yystack->yytops.yysize; yyk += 1)
-    yymarkStackDeleted (yystack, yyk);
-  yyremoveDeletes (yystack);
-  yycompressStack (yystack);
-
-  /* Now pop stack until we find a state that shifts the error token. */
-  yystack->yyerrState = 3;
-  while (yystack->yytops.yystates[0] != NULL)
+  if (yyk >= yystackp->yytops.yysize)
+    yyFail (yystackp][]b4_lpure_args[, NULL);
+  for (yyk += 1; yyk < yystackp->yytops.yysize; yyk += 1)
+    yymarkStackDeleted (yystackp, yyk);
+  yyremoveDeletes (yystackp);
+  yycompressStack (yystackp);
+
+  /* Now pop stack until we find a state that shifts the error token.  */
+  yystackp->yyerrState = 3;
+  while (yystackp->yytops.yystates[0] != NULL)
     {
-      yyGLRState *yys = yystack->yytops.yystates[0];
+      yyGLRState *yys = yystackp->yytops.yystates[0];
       yyj = yypact[yys->yylrState];
       if (! yyis_pact_ninf (yyj))
 	{
@@ -1913,33 +2091,30 @@ yyrecoverSyntaxError (yyGLRStack* yystack,
 	    {
 	      /* Shift the error token having adjusted its location.  */
 	      YYLTYPE yyerrloc;]b4_location_if([[
-	      yystack->yyerror_range[2].yystate.yyloc = *yyllocp;
-	      YYLLOC_DEFAULT (yyerrloc, yystack->yyerror_range, 2);]])[
+             yystackp->yyerror_range[2].yystate.yyloc = yylloc;
+	      YYLLOC_DEFAULT (yyerrloc, yystackp->yyerror_range, 2);]])[
 	      YY_SYMBOL_PRINT ("Shifting", yystos[yytable[yyj]],
-			       yylvalp, &yyerrloc);
-	      YYDPRINTF ((stderr, "\n"));
-	      yyglrShift (yystack, 0, yytable[yyj],
-			  yys->yyposn, *yylvalp, &yyerrloc]b4_user_args[);
-	      yys = yystack->yytops.yystates[0];
+                              &yylval, &yyerrloc);
+	      yyglrShift (yystackp, 0, yytable[yyj],
+                         yys->yyposn, &yylval, &yyerrloc);
+	      yys = yystackp->yytops.yystates[0];
 	      break;
 	    }
 	}
-]b4_location_if([[      yystack->yyerror_range[1].yystate.yyloc = yys->yyloc;]])[
-      yydestruct ("Error: popping",
-		  yystos[yys->yylrState],
-	          &yys->yysemantics.yysval]b4_location_if([, &yys->yyloc])[);
-      yystack->yytops.yystates[0] = yys->yypred;
-      yystack->yynextFree -= 1;
-      yystack->yyspaceLeft += 1;
+]b4_location_if([[      yystackp->yyerror_range[1].yystate.yyloc = yys->yyloc;]])[
+      yydestroyGLRState ("Error: popping", yys]b4_user_args[);
+      yystackp->yytops.yystates[0] = yys->yypred;
+      yystackp->yynextFree -= 1;
+      yystackp->yyspaceLeft += 1;
     }
-  if (yystack->yytops.yystates[0] == NULL)
-    yyFail (yystack][]b4_lpure_args[, NULL);
+  if (yystackp->yytops.yystates[0] == NULL)
+    yyFail (yystackp][]b4_lpure_args[, NULL);
 }
 
 #define YYCHK1(YYE)							     \
   do {									     \
     switch (YYE) {							     \
-    default:								     \
+    case yyok:								     \
       break;								     \
     case yyabort:							     \
       goto yyabortlab;							     \
@@ -1947,8 +2122,10 @@ yyrecoverSyntaxError (yyGLRStack* yystack,
       goto yyacceptlab;							     \
     case yyerr:								     \
       goto yyuser_error;						     \
+    default:								     \
+      goto yybuglab;							     \
     }									     \
-  } while (0)
+  } while (YYID (0))
 
 
 /*----------.
@@ -1960,17 +2137,8 @@ yyrecoverSyntaxError (yyGLRStack* yystack,
   int yyresult;
   yySymbol yytoken;
   yyGLRStack yystack;
+  yyGLRStack* const yystackp = &yystack;
   size_t yyposn;
-]b4_pure_if(
-[
-  YYSTYPE yylval;
-  YYLTYPE yylloc;
-  #undef yychar
-  #define yychar (yystack.yyrawchar)
-])[
-
-  YYSTYPE* const yylvalp = &yylval;
-  YYLTYPE* const yyllocp = &yylloc;
 
   YYDPRINTF ((stderr, "Starting parse\n"));
 
@@ -1985,38 +2153,40 @@ yyrecoverSyntaxError (yyGLRStack* yystack,
 m4_ifdef([b4_initial_action], [
 m4_pushdef([b4_at_dollar],     [yylloc])dnl
 m4_pushdef([b4_dollar_dollar], [yylval])dnl
-  /* User initialization code. */
+  /* User initialization code.  */
   b4_initial_action
 m4_popdef([b4_dollar_dollar])dnl
 m4_popdef([b4_at_dollar])dnl
 /* Line __line__ of glr.c.  */
 b4_syncline([@oline@], [@ofile@])])dnl
 [
-  if (! yyinitGLRStack (&yystack, YYINITDEPTH))
-    goto yyoverflowlab;
-  switch (setjmp (yystack.yyexception_buffer))
+  if (! yyinitGLRStack (yystackp, YYINITDEPTH))
+    goto yyexhaustedlab;
+  switch (YYSETJMP (yystack.yyexception_buffer))
     {
+    case 0: break;
     case 1: goto yyabortlab;
-    case 2: goto yyoverflowlab;
+    case 2: goto yyexhaustedlab;
+    default: goto yybuglab;
     }
   yystack.yytokenp = &yytoken;
-  yyglrShift (&yystack, 0, 0, 0, yylval, &yylloc]b4_user_args[);
+  yyglrShift (&yystack, 0, 0, 0, &yylval, &yylloc);
   yyposn = 0;
 
-  while (yytrue)
+  while (YYID (yytrue))
     {
       /* For efficiency, we have two loops, the first of which is
 	 specialized to deterministic operation (single stack, no
 	 potential ambiguity).  */
       /* Standard mode */
-      while (yytrue)
+      while (YYID (yytrue))
 	{
 	  yyRuleNum yyrule;
 	  int yyaction;
 	  const short int* yyconflicts;
 
 	  yyStateNum yystate = yystack.yytops.yystates[0]->yylrState;
-          YYDPRINTF ((stderr, "Entering state %d\n", yystate));
+	  YYDPRINTF ((stderr, "Entering state %d\n", yystate));
 	  if (yystate == YYFINAL)
 	    goto yyacceptlab;
 	  if (yyisDefaultedState (yystate))
@@ -2024,11 +2194,11 @@ b4_syncline([@oline@], [@ofile@])])dnl
 	      yyrule = yydefaultAction (yystate);
 	      if (yyrule == 0)
 		{
-]b4_location_if([[		  yystack.yyerror_range[1].yystate.yyloc = *yyllocp;]])[
-		  yyreportSyntaxError (&yystack, yylvalp, yyllocp]b4_user_args[);
+]b4_location_if([[               yystack.yyerror_range[1].yystate.yyloc = yylloc;]])[
+                 yyreportSyntaxError (&yystack]b4_user_args[);
 		  goto yyuser_error;
 		}
-	      YYCHK1 (yyglrReduce (&yystack, 0, yyrule, yytrue]b4_lpure_args[));
+	      YYCHK1 (yyglrReduce (&yystack, 0, yyrule, yytrue]b4_user_args[));
 	    }
 	  else
 	    {
@@ -2037,45 +2207,86 @@ b4_syncline([@oline@], [@ofile@])])dnl
 		  YYDPRINTF ((stderr, "Reading a token: "));
 		  yychar = YYLEX;
 		  yytoken = YYTRANSLATE (yychar);
-                  YY_SYMBOL_PRINT ("Next token is", yytoken, yylvalp, yyllocp);
-                  YYDPRINTF ((stderr, "\n"));
+                 YY_SYMBOL_PRINT ("Next token is", yytoken, &yylval, &yylloc);
 		}
 	      yygetLRActions (yystate, yytoken, &yyaction, &yyconflicts);
 	      if (*yyconflicts != 0)
 		break;
 	      if (yyisShiftAction (yyaction))
 		{
-		  YY_SYMBOL_PRINT ("Shifting", yytoken, yylvalp, yyllocp);
-	          YYDPRINTF ((stderr, "\n"));
+                 YY_SYMBOL_PRINT ("Shifting", yytoken, &yylval, &yylloc);
 		  if (yytoken != YYEOF)
 		    yytoken = YYEMPTY;
 		  yyposn += 1;
-		  yyglrShift (&yystack, 0, yyaction, yyposn,
-		              yylval, yyllocp]b4_user_args[);
+                 yyglrShift (&yystack, 0, yyaction, yyposn, &yylval, &yylloc);
 		  if (0 < yystack.yyerrState)
 		    yystack.yyerrState -= 1;
 		}
 	      else if (yyisErrorAction (yyaction))
 		{
-]b4_location_if([[		  yystack.yyerror_range[1].yystate.yyloc = *yyllocp;]])[
-		  yyreportSyntaxError (&yystack, yylvalp, yyllocp]b4_user_args[);
+]b4_location_if([[               yystack.yyerror_range[1].yystate.yyloc = yylloc;]])[
+                 yyreportSyntaxError (&yystack]b4_user_args[);
 		  goto yyuser_error;
 		}
 	      else
-		YYCHK1 (yyglrReduce (&yystack, 0, -yyaction, yytrue]b4_lpure_args[));
+		YYCHK1 (yyglrReduce (&yystack, 0, -yyaction, yytrue]b4_user_args[));
 	    }
 	}
 
-      while (yytrue)
+      while (YYID (yytrue))
 	{
+	  yySymbol yytoken_to_shift;
 	  size_t yys;
 	  size_t yyn = yystack.yytops.yysize;
+
+	  /* yyprocessOneStack returns one of three things:
+
+	      - An error flag.  If the caller is yyprocessOneStack, it
+		immediately returns as well.  When the caller is finally
+		yyparse, it jumps to an error label via YYCHK1.
+
+	      - yyok, but yyprocessOneStack has invoked yymarkStackDeleted
+		(&yystack, yys), which sets the top state of yys to NULL.  Thus,
+		yyparse's following invocation of yyremoveDeletes will remove
+		the stack.
+
+	      - yyok, when ready to shift a token.
+
+	     Except in the first case, yyparse will invoke yyremoveDeletes and
+	     then shift the next token onto all remaining stacks.  This
+	     synchronization of the shift (that is, after all preceding
+	     reductions on all stacks) helps prevents double destructor calls
+	     on yylval in the event of memory exhaustion.  */
+
 	  for (yys = 0; yys < yyn; yys += 1)
-	    YYCHK1 (yyprocessOneStack (&yystack, yys, yyposn,
-				       yylvalp, yyllocp]b4_lpure_args[));
+           YYCHK1 (yyprocessOneStack (&yystack, yys, yyposn]b4_lpure_args[));
+	  yyremoveDeletes (&yystack);
+	  yyn = yystack.yytops.yysize;
+
+	  /* If any yyglrShift call fails, it will fail after shifting.  Thus,
+	     a copy of yylval will already be on stack 0 in the event of a
+	     failure in the following loop.  Thus, yytoken is set to YYEMPTY
+	     before the loop to make sure the user destructor for yylval isn't
+	     called twice.  */
+	  yytoken_to_shift = yytoken;
 	  yytoken = YYEMPTY;
 	  yyposn += 1;
-	  yyremoveDeletes (&yystack);
+	  for (yys = 0; yys < yyn; yys += 1)
+	    {
+	      int yyaction;
+	      const short int* yyconflicts;
+	      yyStateNum yystate = yystack.yytops.yystates[yys]->yylrState;
+	      yygetLRActions (yystate, yytoken_to_shift, &yyaction,
+			      &yyconflicts);
+	      /* Note that yyconflicts were handled by yyprocessOneStack.  */
+	      YYDPRINTF ((stderr, "On stack %lu, ", (unsigned long int) yys));
+             YY_SYMBOL_PRINT ("shifting", yytoken_to_shift, &yylval, &yylloc);
+	      yyglrShift (&yystack, yys, yyaction, yyposn,
+                         &yylval, &yylloc);
+	      YYDPRINTF ((stderr, "Stack %lu now in state #%d\n",
+			  (unsigned long int) yys,
+			  yystack.yytops.yystates[yys]->yylrState));
+	    }
 	  if (yystack.yytops.yysize == 0)
 	    {
 	      yyundeleteLastStack (&yystack);
@@ -2083,8 +2294,8 @@ b4_syncline([@oline@], [@ofile@])])dnl
 		yyFail (&yystack][]b4_lpure_args[, YY_("syntax error"));
 	      YYCHK1 (yyresolveStack (&yystack]b4_user_args[));
 	      YYDPRINTF ((stderr, "Returning to deterministic operation.\n"));
-]b4_location_if([[	      yystack.yyerror_range[1].yystate.yyloc = *yyllocp;]])[
-	      yyreportSyntaxError (&yystack, yylvalp, yyllocp]b4_user_args[);
+]b4_location_if([[           yystack.yyerror_range[1].yystate.yyloc = yylloc;]])[
+             yyreportSyntaxError (&yystack]b4_user_args[);
 	      goto yyuser_error;
 	    }
 	  else if (yystack.yytops.yysize == 1)
@@ -2097,7 +2308,7 @@ b4_syncline([@oline@], [@ofile@])])dnl
 	}
       continue;
     yyuser_error:
-      yyrecoverSyntaxError (&yystack, yylvalp, yyllocp]b4_user_args[);
+      yyrecoverSyntaxError (&yystack]b4_user_args[);
       yyposn = yystack.yytops.yystates[0]->yyposn;
     }
 
@@ -2105,28 +2316,60 @@ b4_syncline([@oline@], [@ofile@])])dnl
   yyresult = 0;
   goto yyreturn;
 
+ yybuglab:
+  YYASSERT (yyfalse);
+  goto yyabortlab;
+
  yyabortlab:
   yyresult = 1;
   goto yyreturn;
 
- yyoverflowlab:
-  yyerror (]b4_lyyerror_args[YY_("parser stack overflow"));
+ yyexhaustedlab:
+  yyerror (]b4_lyyerror_args[YY_("memory exhausted"));
   yyresult = 2;
-  /* Fall through.  */
+  goto yyreturn;
 
  yyreturn:
   if (yytoken != YYEOF && yytoken != YYEMPTY)
-    yydestruct ("Error: discarding lookahead",
-                yytoken, yylvalp]b4_location_if([, yyllocp])[);
+    yydestruct ("Cleanup: discarding lookahead",
+               yytoken, &yylval]b4_location_if([, &yylloc])[]b4_user_args[);
+
+  /* If the stack is well-formed, pop the stack until it is empty,
+     destroying its entries as we go.  But free the stack regardless
+     of whether it is well-formed.  */
+  if (yystack.yyitems)
+    {
+      yyGLRState** yystates = yystack.yytops.yystates;
+      if (yystates)
+	{
+	  size_t yysize = yystack.yytops.yysize;
+	  size_t yyk;
+	  for (yyk = 0; yyk < yysize; yyk += 1)
+	    if (yystates[yyk])
+	      {
+		while (yystates[yyk])
+		  {
+		    yyGLRState *yys = yystates[yyk];
+]b4_location_if([[		    yystack.yyerror_range[1].yystate.yyloc = yys->yyloc;]]
+)[		    yydestroyGLRState ("Cleanup: popping", yys]b4_user_args[);
+		    yystates[yyk] = yys->yypred;
+		    yystack.yynextFree -= 1;
+		    yystack.yyspaceLeft += 1;
+		  }
+		break;
+	      }
+	}
+      yyfreeGLRStack (&yystack);
+    }
 
-  yyfreeGLRStack (&yystack);
   return yyresult;
 }
 
 /* DEBUGGING ONLY */
 #ifdef YYDEBUG
-static void yypstack (yyGLRStack* yystack, size_t yyk) ATTRIBUTE_UNUSED;
-static void yypdumpstack (yyGLRStack* yystack) ATTRIBUTE_UNUSED;
+static void yypstack (yyGLRStack* yystackp, size_t yyk)
+  __attribute__ ((__unused__));
+static void yypdumpstack (yyGLRStack* yystackp) __attribute__ ((__unused__));
 
 static void
 yy_yypstack (yyGLRState* yys)
@@ -2150,23 +2393,23 @@ yypstates (yyGLRState* yyst)
 }
 
 static void
-yypstack (yyGLRStack* yystack, size_t yyk)
+yypstack (yyGLRStack* yystackp, size_t yyk)
 {
-  yypstates (yystack->yytops.yystates[yyk]);
+  yypstates (yystackp->yytops.yystates[yyk]);
 }
 
 #define YYINDEX(YYX)							     \
-    ((YYX) == NULL ? -1 : (yyGLRStackItem*) (YYX) - yystack->yyitems)
+    ((YYX) == NULL ? -1 : (yyGLRStackItem*) (YYX) - yystackp->yyitems)
 
 
 static void
-yypdumpstack (yyGLRStack* yystack)
+yypdumpstack (yyGLRStack* yystackp)
 {
   yyGLRStackItem* yyp;
   size_t yyi;
-  for (yyp = yystack->yyitems; yyp < yystack->yynextFree; yyp += 1)
+  for (yyp = yystackp->yyitems; yyp < yystackp->yynextFree; yyp += 1)
     {
-      fprintf (stderr, "%3lu. ", (unsigned long int) (yyp - yystack->yyitems));
+      fprintf (stderr, "%3lu. ", (unsigned long int) (yyp - yystackp->yyitems));
       if (*(yybool *) yyp)
 	{
 	  fprintf (stderr, "Res: %d, LR State: %d, posn: %lu, pred: %ld",
@@ -2187,9 +2430,9 @@ yypdumpstack (yyGLRStack* yystack)
       fprintf (stderr, "\n");
     }
   fprintf (stderr, "Tops:");
-  for (yyi = 0; yyi < yystack->yytops.yysize; yyi += 1)
+  for (yyi = 0; yyi < yystackp->yytops.yysize; yyi += 1)
     fprintf (stderr, "%lu: %ld; ", (unsigned long int) yyi,
-	     (long int) YYINDEX (yystack->yytops.yystates[yyi]));
+	     (long int) YYINDEX (yystackp->yytops.yystates[yyi]));
   fprintf (stderr, "\n");
 }
 #endif
@@ -2199,39 +2442,14 @@ b4_epilogue
 m4_if(b4_defines_flag, 0, [],
 [@output @output_header_name@
 b4_copyright([Skeleton parser for GLR parsing with Bison],
-  [2002, 2003, 2004, 2005])
+	     [2002, 2003, 2004, 2005])[
 
-b4_token_defines(b4_tokens)
-
-#if ! defined (YYSTYPE) && ! defined (YYSTYPE_IS_DECLARED)
-m4_ifdef([b4_stype],
-[b4_syncline([b4_stype_line], [b4_filename])
-typedef union m4_bregexp(b4_stype, [^{], [YYSTYPE ])b4_stype YYSTYPE;
-/* Line __line__ of glr.c.  */
-b4_syncline([@oline@], [@ofile@])],
-[typedef int YYSTYPE;])
-# define YYSTYPE_IS_DECLARED 1
-# define YYSTYPE_IS_TRIVIAL 1
-#endif
+/* C GLR parser skeleton written by Paul Hilfinger.  */
+]
 
-b4_pure_if([],
-[extern YYSTYPE b4_prefix[]lval;])
+b4_shared_declarations
 
-#if ! defined (YYLTYPE) && ! defined (YYLTYPE_IS_DECLARED)
-typedef struct YYLTYPE
-{
-b4_location_if([
-  int first_line;
-  int first_column;
-  int last_line;
-  int last_column;
-],[
-  char yydummy;
-])
-} YYLTYPE;
-# define YYLTYPE_IS_DECLARED 1
-# define YYLTYPE_IS_TRIVIAL 1
-#endif
+extern YYSTYPE b4_prefix[]lval;
 
 b4_location_if([b4_pure_if([],
 [extern YYLTYPE b4_prefix[]lloc;])