X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/742e4900c8b05c8c1f56985288141c890f1e9c73..5422471cbb68d8b5775046702cc92209b0718f58:/tests/glr-regression.at
diff --git a/tests/glr-regression.at b/tests/glr-regression.at
index 598ab8e8..71f6e6d5 100644
--- a/tests/glr-regression.at
+++ b/tests/glr-regression.at
@@ -1,40 +1,43 @@
# Checking GLR Parsing: Regression Tests -*- Autotest -*-
-# Copyright (C) 2002, 2003, 2005, 2006 Free Software Foundation, Inc.
-# This program is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 2, or (at your option)
-# any later version.
+# Copyright (C) 2002-2003, 2005-2007, 2009-2015 Free Software
+# Foundation, Inc.
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
-
+#
# You should have received a copy of the GNU General Public License
-# along with this program; if not, write to the Free Software
-# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
-# 02110-1301, USA.
+# along with this program. If not, see .
AT_BANNER([[GLR Regression Tests]])
-## --------------------------- ##
-## Badly Collapsed GLR States. ##
-## --------------------------- ##
+## ---------------------------- ##
+## Badly Collapsed GLR States. ##
+## ---------------------------- ##
AT_SETUP([Badly Collapsed GLR States])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr1.y],
[[/* Regression Test: Improper state compression */
/* Reported by Scott McPeak */
%{
#include
+#include
+#include
#define YYSTYPE int
static YYSTYPE exprMerge (YYSTYPE x0, YYSTYPE x1);
-int yylex (void);
-void yyerror (char const *msg);
+]AT_YYERROR_DECLARE[
+]AT_YYLEX_DECLARE[
%}
@@ -64,38 +67,31 @@ static YYSTYPE exprMerge (YYSTYPE x0, YYSTYPE x1)
return 0;
}
+const char *input = YY_NULLPTR;
+
int
-main (void)
+main (int argc, const char* argv[])
{
+ assert (argc == 2);
+ input = argv[1];
return yyparse ();
}
-void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
+]AT_YYERROR_DEFINE[
int
yylex (void)
{
- for (;;)
- {
- int ch = getchar ();
- if (ch == EOF)
- return 0;
- else if (ch == 'B' || ch == 'P')
- return ch;
- }
+ return *input++;
}
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr1.c glr-regr1.y]], 0, [],
-[glr-regr1.y: conflicts: 1 shift/reduce
-])
+AT_BISON_CHECK([[-o glr-regr1.c glr-regr1.y]], 0, [],
+[[glr-regr1.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
+]])
AT_COMPILE([glr-regr1])
-AT_CHECK([[echo BPBPB | ./glr-regr1]], 0,
+AT_PARSER_CHECK([[./glr-regr1 BPBPB]], 0,
[[E -> 'B'
E -> 'B'
E -> E 'P' E
@@ -109,12 +105,13 @@ E -> E 'P' E
AT_CLEANUP
-## ------------------------------------------------------------ ##
-## Improper handling of embedded actions and $-N in GLR parsers ##
-## ------------------------------------------------------------ ##
+## -------------------------------------------------------------- ##
+## Improper handling of embedded actions and $-N in GLR parsers. ##
+## -------------------------------------------------------------- ##
AT_SETUP([Improper handling of embedded actions and dollar(-N) in GLR parsers])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr2a.y],
[[/* Regression Test: Improper handling of embedded actions and $-N */
/* Reported by S. Eken */
@@ -126,8 +123,9 @@ AT_DATA_GRAMMAR([glr-regr2a.y],
#include
#include
#include
- int yylex (void);
- void yyerror (char const *);
+ #include
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
%}
%glr-parser
@@ -167,15 +165,17 @@ var_printer: 'v'
{ printf ("Variable: '%s'\n", $-1); }
%%
-
-FILE *input = NULL;
+]AT_YYERROR_DEFINE[
+FILE *input;
int
yylex (void)
{
char buf[50];
char *s;
- switch (fscanf (input, " %1[a-z,]", buf)) {
+ assert (!feof (stdin));
+ switch (fscanf (input, " %1[a-z,]", buf))
+ {
case 1:
return buf[0];
case EOF:
@@ -185,63 +185,78 @@ yylex (void)
}
if (fscanf (input, "%49s", buf) != 1)
return 0;
- if (sizeof buf - 1 <= strlen (buf))
- abort ();
+ assert (strlen (buf) < sizeof buf - 1);
s = (char *) malloc (strlen (buf) + 1);
strcpy (s, buf);
yylval = s;
return 'V';
}
-void
-yyerror (char const *s)
-{ printf ("%s\n", s);
-}
-
int
main (int argc, char **argv)
{
+ int res;
input = stdin;
- if (argc == 2 && !(input = fopen (argv[1], "r"))) return 3;
- return yyparse ();
+ if (argc == 2 && !(input = fopen (argv[1], "r")))
+ return 3;
+ res = yyparse ();
+ if (argc == 2 && fclose (input))
+ return 4;
+ return res;
}
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr2a.c glr-regr2a.y]], 0, [],
-[glr-regr2a.y: conflicts: 2 shift/reduce
-])
+AT_BISON_CHECK([[-o glr-regr2a.c glr-regr2a.y]], 0, [],
+[[glr-regr2a.y: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
+]])
AT_COMPILE([glr-regr2a])
-AT_CHECK([[echo s VARIABLE_1 t v x q | ./glr-regr2a]], 0,
+AT_DATA([input1.txt],
+[[s VARIABLE_1 t v x q
+]])
+AT_PARSER_CHECK([[./glr-regr2a input1.txt]], 0,
[[Variable: 'VARIABLE_1'
-]], [])
-AT_CHECK([[echo s VARIABLE_1 , ANOTHER_VARIABLE_2 t e | ./glr-regr2a]], 0,
+]])
+
+AT_DATA([input2.txt],
+[[s VARIABLE_1 , ANOTHER_VARIABLE_2 t e
+]])
+AT_PARSER_CHECK([[./glr-regr2a input2.txt]],
+0,
[[Varlist: 'VARIABLE_1,ANOTHER_VARIABLE_2'
]])
-AT_CHECK([[echo s VARIABLE_3 t v x | ./glr-regr2a]], 0,
+
+AT_DATA([input3.txt],
+[[s VARIABLE_3 t v x
+]])
+AT_PARSER_CHECK([[./glr-regr2a input3.txt]], 0,
[[Variable: 'VARIABLE_3'
-]], [])
+]])
AT_CLEANUP
-## ------------------------------------------------------------ ##
-## Improper merging of GLR delayed action sets ##
-## ------------------------------------------------------------ ##
+## --------------------------------------------- ##
+## Improper merging of GLR delayed action sets. ##
+## --------------------------------------------- ##
AT_SETUP([Improper merging of GLR delayed action sets])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr3.y],
[[/* Regression Test: Improper merging of GLR delayed action sets. */
/* Reported by M. Rosien */
%{
#include
+#include
#include
+#include
static int MergeRule (int x0, int x1);
-static void yyerror (char const * s);
-int yylex (void);
+]AT_YYERROR_DECLARE[
+]AT_YYLEX_DECLARE[
#define RULE(x) (1 << (x))
@@ -282,15 +297,14 @@ NT6 : P1 NT1 O1 T3 P2 { $$ = RULE(11) | $2; } %merge
%%
-static int MergeRule (int x0, int x1) {
+static int
+MergeRule (int x0, int x1)
+{
return x0 | x1;
}
+]AT_YYERROR_DEFINE[
-static void yyerror(char const * s) {
- fprintf(stderr,"error: %s\n",s);
-}
-
-FILE *input = NULL;
+FILE *input = YY_NULLPTR;
int P[] = { P1, P2 };
int O[] = { O1, O2 };
@@ -299,6 +313,7 @@ int T[] = { T1, T2, T3, T4 };
int yylex (void)
{
char inp[3];
+ assert (!feof (stdin));
if (fscanf (input, "%2s", inp) == EOF)
return 0;
switch (inp[0])
@@ -310,32 +325,46 @@ int yylex (void)
return BAD_CHAR;
}
-int main(int argc, char* argv[]) {
+int
+main (int argc, char* argv[])
+{
+ int res;
input = stdin;
- if (argc == 2 && !(input = fopen (argv[1], "r"))) return 3;
- return yyparse ();
+ if (argc == 2 && !(input = fopen (argv[1], "r")))
+ return 3;
+ res = yyparse ();
+ if (argc == 2 && fclose (input))
+ return 4;
+ return res;
}
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr3.c glr-regr3.y]], 0, [],
-[glr-regr3.y: conflicts: 1 shift/reduce, 1 reduce/reduce
-])
+AT_BISON_CHECK([[-o glr-regr3.c glr-regr3.y]], 0, [],
+[[glr-regr3.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
+glr-regr3.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr3])
-AT_CHECK([[echo p1 t4 o2 p1 p1 t1 o1 t2 p2 o1 t3 p2 p2 | ./glr-regr3]], 0,
+AT_DATA([input.txt],
+[[p1 t4 o2 p1 p1 t1 o1 t2 p2 o1 t3 p2 p2
+]])
+AT_PARSER_CHECK([[./glr-regr3 input.txt]],
+0,
[[Result: 1c04
-]], [])
+]])
AT_CLEANUP
-## ------------------------------------------------------------------------- ##
-## Duplicate representation of merged trees. See ##
-## . ##
-## ------------------------------------------------------------------------- ##
+## ---------------------------------------------------------------------- ##
+## Duplicate representation of merged trees. See ##
+## . ##
+## ---------------------------------------------------------------------- ##
AT_SETUP([Duplicate representation of merged trees])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr4.y],
[[
%union { char *ptr; }
@@ -348,8 +377,10 @@ AT_DATA_GRAMMAR([glr-regr4.y],
#include
static char *merge (YYSTYPE, YYSTYPE);
static char *make_value (char const *, char const *);
- static void yyerror (char const *);
- static int yylex (void);
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
+ static char *ptrs[100];
+ static char **ptrs_next = ptrs;
%}
%%
@@ -371,25 +402,23 @@ A2: 'a' { $$ = make_value ("A2", "'a'"); } ;
B: 'a' { $$ = make_value ("B", "'a'"); } ;
%%
-
-static int
-yylex (void)
-{
- static char const *input = "a";
- return *input++;
-}
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE(["a"])[
int
main (void)
{
- return yyparse ();
+ int status = yyparse ();
+ while (ptrs_next != ptrs)
+ free (*--ptrs_next);
+ return status;
}
static char *
make_value (char const *parent, char const *child)
{
char const format[] = "%s <- %s";
- char *value =
+ char *value = *ptrs_next++ =
(char *) malloc (strlen (parent) + strlen (child) + sizeof format);
sprintf (value, format, parent, child);
return value;
@@ -399,45 +428,41 @@ static char *
merge (YYSTYPE s1, YYSTYPE s2)
{
char const format[] = "merge{ %s and %s }";
- char *value =
+ char *value = *ptrs_next++ =
(char *) malloc (strlen (s1.ptr) + strlen (s2.ptr) + sizeof format);
sprintf (value, format, s1.ptr, s2.ptr);
return value;
}
-
-static void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr4.c glr-regr4.y]], 0, [],
-[glr-regr4.y: conflicts: 1 reduce/reduce
-])
+AT_BISON_CHECK([[-o glr-regr4.c glr-regr4.y]], 0, [],
+[[glr-regr4.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr4])
-AT_CHECK([[./glr-regr4]], 0,
+AT_PARSER_CHECK([[./glr-regr4]], 0,
[[merge{ S <- merge{ A <- A1 <- 'a' and A <- A2 <- 'a' } and S <- B <- 'a' }
]], [])
AT_CLEANUP
-## -------------------------------------------------------------------------- ##
-## User destructor for unresolved GLR semantic value. See ##
-## . ##
-## -------------------------------------------------------------------------- ##
+## ------------------------------------------------------------------------- ##
+## User destructor for unresolved GLR semantic value. See ##
+## . ##
+## ------------------------------------------------------------------------- ##
AT_SETUP([User destructor for unresolved GLR semantic value])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr5.y],
[[
%{
#include
#include
- static void yyerror (char const *);
- static int yylex (void);
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
enum { MAGIC_VALUE = -1057808125 }; /* originally chosen at random */
%}
@@ -461,53 +486,39 @@ start:
;
%%
-
-static int
-yylex (void)
-{
- static char const *input = "a";
- return *input++;
-}
-
-static void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
-int
-main (void)
-{
- return yyparse () != 1;
-}
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE(["a"])[
+]AT_MAIN_DEFINE[
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr5.c glr-regr5.y]], 0, [],
-[glr-regr5.y: conflicts: 1 reduce/reduce
-])
+AT_BISON_CHECK([[-o glr-regr5.c glr-regr5.y]], 0, [],
+[[glr-regr5.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr5])
-AT_CHECK([[./glr-regr5]], 0, [],
+AT_PARSER_CHECK([[./glr-regr5]], 1, [],
[syntax is ambiguous
])
AT_CLEANUP
-## -------------------------------------------------------------------------- ##
-## User destructor after an error during a split parse. See ##
-## . ##
-## -------------------------------------------------------------------------- ##
+## ------------------------------------------------------------------------- ##
+## User destructor after an error during a split parse. See ##
+## . ##
+## ------------------------------------------------------------------------- ##
AT_SETUP([User destructor after an error during a split parse])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr6.y],
[[
%{
#include
#include
- static void yyerror (char const *);
- static int yylex (void);
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
%}
%glr-parser
@@ -523,33 +534,18 @@ AT_DATA_GRAMMAR([glr-regr6.y],
start: 'a' | 'a' ;
%%
-
-static int
-yylex (void)
-{
- static char const *input = "a";
- return *input++;
-}
-
-static void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
-int
-main (void)
-{
- return yyparse () != 1;
-}
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE(["a"])[
+]AT_MAIN_DEFINE[
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr6.c glr-regr6.y]], 0, [],
-[glr-regr6.y: conflicts: 1 reduce/reduce
-])
+AT_BISON_CHECK([[-o glr-regr6.c glr-regr6.y]], 0, [],
+[[glr-regr6.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr6])
-AT_CHECK([[./glr-regr6]], 0,
+AT_PARSER_CHECK([[./glr-regr6]], 1,
[Destructor called.
],
[syntax is ambiguous
@@ -559,28 +555,34 @@ AT_CLEANUP
## ------------------------------------------------------------------------- ##
-## Duplicated user destructor for lookahead. See ##
+## Duplicated user destructor for lookahead. See ##
## . ##
## ------------------------------------------------------------------------- ##
AT_SETUP([Duplicated user destructor for lookahead])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr7.y],
[[
%{
#include
#include
- static void yyerror (char const *);
- static int yylex (void);
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
#define YYSTACKEXPANDABLE 0
+ typedef struct count_node {
+ int count;
+ struct count_node *prev;
+ } count_node;
+ static count_node *tail;
%}
%glr-parser
-%union { int *count; }
-%type 'a'
+%union { count_node *node; }
+%type 'a'
%destructor {
- if ((*$$)++)
+ if ($$->count++)
fprintf (stderr, "Destructor called on same value twice.\n");
} 'a'
@@ -599,35 +601,40 @@ stack2: 'a' ;
static int
yylex (void)
{
- yylval.count = (int *) malloc (sizeof (int));
- if (!yylval.count)
+ yylval.node = (count_node*) malloc (sizeof *yylval.node);
+ if (!yylval.node)
{
fprintf (stderr, "Test inconclusive.\n");
exit (EXIT_FAILURE);
}
- *yylval.count = 0;
+ yylval.node->count = 0;
+ yylval.node->prev = tail;
+ tail = yylval.node;
return 'a';
}
-static void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
+]AT_YYERROR_DEFINE[
int
main (void)
{
- return yyparse ();
+ int status = yyparse ();
+ while (tail)
+ {
+ count_node *prev = tail->prev;
+ free (tail);
+ tail = prev;
+ }
+ return status;
}
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr7.c glr-regr7.y]], 0, [],
-[glr-regr7.y: conflicts: 2 reduce/reduce
-])
+AT_BISON_CHECK([[-o glr-regr7.c glr-regr7.y]], 0, [],
+[[glr-regr7.y: warning: 2 reduce/reduce conflicts [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr7])
-AT_CHECK([[./glr-regr7]], 2, [],
+AT_PARSER_CHECK([[./glr-regr7]], 2, [],
[memory exhausted
])
@@ -636,21 +643,21 @@ AT_CLEANUP
## ------------------------------------------------------------------------- ##
## Incorrect default location for empty right-hand sides. Adapted from bug ##
-## report by Claudia Hermann. ##
+## report by Claudia Hermann. ##
## See http://lists.gnu.org/archive/html/bug-bison/2005-10/msg00069.html and ##
## http://lists.gnu.org/archive/html/bug-bison/2005-10/msg00072.html ##
## ------------------------------------------------------------------------- ##
AT_SETUP([Incorrectly initialized location for empty right-hand side in GLR])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr8.y],
[[
%{
#include
#include
- static void yyerror (char const *);
- static int yylex (void);
- static void yyerror (char const *msg);
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
%}
%token T_CONSTANT
@@ -662,34 +669,29 @@ AT_DATA_GRAMMAR([glr-regr8.y],
%%
-PortClause : T_PORT InterfaceDeclaration T_PORT
- { printf("%d/%d - %d/%d - %d/%d\n",
- @1.first_column, @1.last_column,
- @2.first_column, @2.last_column,
- @3.first_column, @3.last_column); }
- ;
+PortClause : T_PORT InterfaceDeclaration T_PORT
+ { printf("%d/%d - %d/%d - %d/%d\n",
+ @1.first_column, @1.last_column,
+ @2.first_column, @2.last_column,
+ @3.first_column, @3.last_column); }
+ ;
-InterfaceDeclaration : OptConstantWord %dprec 1
- | OptSignalWord %dprec 2
- ;
+InterfaceDeclaration : OptConstantWord %dprec 1
+ | OptSignalWord %dprec 2
+ ;
-OptConstantWord : /* empty */
- | T_CONSTANT
- ;
+OptConstantWord : /* empty */
+ | T_CONSTANT
+ ;
-OptSignalWord : /* empty */
- { printf("empty: %d/%d\n", @$.first_column, @$.last_column); }
- | T_SIGNAL
- ;
+OptSignalWord : /* empty */
+ { printf("empty: %d/%d\n", @$.first_column, @$.last_column); }
+ | T_SIGNAL
+ ;
%%
-void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
+]AT_YYERROR_DEFINE[
static int lexIndex;
int yylex (void)
@@ -697,6 +699,8 @@ int yylex (void)
lexIndex += 1;
switch (lexIndex)
{
+ default:
+ abort ();
case 1:
yylloc.first_column = 1;
yylloc.last_column = 9;
@@ -705,25 +709,21 @@ int yylex (void)
yylloc.first_column = 13;
yylloc.last_column = 17;
return T_PORT;
- default:
+ case 3:
return 0;
}
}
-int
-main (void)
-{
- yyparse();
- return 0;
-}
+]AT_MAIN_DEFINE[
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr8.c glr-regr8.y]], 0, [],
-[glr-regr8.y: conflicts: 1 reduce/reduce
-])
+AT_BISON_CHECK([[-o glr-regr8.c glr-regr8.y]], 0, [],
+[[glr-regr8.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr8])
-AT_CHECK([[./glr-regr8]], 0,
+AT_PARSER_CHECK([[./glr-regr8]], 0,
[empty: 9/9
1/9 - 9/9 - 13/17
],
@@ -733,19 +733,20 @@ AT_CLEANUP
## ------------------------------------------------------------------------- ##
-## No users destructors if stack 0 deleted. See ##
+## No users destructors if stack 0 deleted. See ##
## . ##
## ------------------------------------------------------------------------- ##
AT_SETUP([No users destructors if stack 0 deleted])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr9.y],
[[
%{
# include
# include
- static void yyerror (char const *);
- static int yylex (void);
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
# define YYSTACKEXPANDABLE 0
static int tokens = 0;
static int destructors = 0;
@@ -781,12 +782,7 @@ yylex (void)
return 'a';
}
-static void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
+]AT_YYERROR_DEFINE[
int
main (void)
{
@@ -800,31 +796,34 @@ main (void)
return !exit_status;
}
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr9.c glr-regr9.y]], 0, [],
-[glr-regr9.y: conflicts: 1 reduce/reduce
-])
+AT_BISON_CHECK([[-o glr-regr9.c glr-regr9.y]], 0, [],
+[[glr-regr9.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr9])
-AT_CHECK([[./glr-regr9]], 0, [],
+AT_PARSER_CHECK([[./glr-regr9]], 0, [],
[memory exhausted
])
AT_CLEANUP
-## ------------------------------------------------------------------------- ##
-## Corrupted semantic options if user action cuts parse. ##
-## ------------------------------------------------------------------------- ##
+## ------------------------------------------------------ ##
+## Corrupted semantic options if user action cuts parse. ##
+## ------------------------------------------------------ ##
AT_SETUP([Corrupted semantic options if user action cuts parse])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr10.y],
[[
%{
+# include
# include
- static void yyerror (char const *);
- static int yylex (void);
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
#define GARBAGE_SIZE 50
static char garbage[GARBAGE_SIZE];
%}
@@ -841,18 +840,8 @@ start:
;
%%
-
-static void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
-static int
-yylex (void)
-{
- return 0;
-}
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE[
int
main (void)
@@ -863,29 +852,31 @@ main (void)
return yyparse ();
}
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr10.c glr-regr10.y]], 0, [],
-[glr-regr10.y: conflicts: 1 reduce/reduce
-])
+AT_BISON_CHECK([[-o glr-regr10.c glr-regr10.y]], 0, [],
+[[glr-regr10.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr10])
-AT_CHECK([[./glr-regr10]], 0, [], [])
+AT_PARSER_CHECK([[./glr-regr10]], 0, [], [])
AT_CLEANUP
-## ------------------------------------------------------------------------- ##
-## Undesirable destructors if user action cuts parse. ##
-## ------------------------------------------------------------------------- ##
+## --------------------------------------------------- ##
+## Undesirable destructors if user action cuts parse. ##
+## --------------------------------------------------- ##
AT_SETUP([Undesirable destructors if user action cuts parse])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr11.y],
[[
%{
# include
- static void yyerror (char const *);
- static int yylex (void);
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
static int destructors = 0;
# define USE(val)
%}
@@ -904,18 +895,8 @@ start:
%%
-static void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
-static int
-yylex (void)
-{
- static char const *input = "a";
- return *input++;
-}
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE(["a"])[
int
main (void)
@@ -929,23 +910,25 @@ main (void)
return exit_status;
}
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr11.c glr-regr11.y]], 0, [],
-[glr-regr11.y: conflicts: 1 reduce/reduce
-])
+AT_BISON_CHECK([[-o glr-regr11.c glr-regr11.y]], 0, [],
+[[glr-regr11.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr11])
-AT_CHECK([[./glr-regr11]], 0, [], [])
+AT_PARSER_CHECK([[./glr-regr11]], 0, [], [])
AT_CLEANUP
-## ------------------------------------------------------------------------- ##
-## Leaked semantic values if user action cuts parse. ##
-## ------------------------------------------------------------------------- ##
+## -------------------------------------------------- ##
+## Leaked semantic values if user action cuts parse. ##
+## -------------------------------------------------- ##
AT_SETUP([Leaked semantic values if user action cuts parse])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr12.y],
[[
%glr-parser
@@ -958,9 +941,10 @@ AT_DATA_GRAMMAR([glr-regr12.y],
%{
# include
+# include
static int merge (YYSTYPE, YYSTYPE);
- static void yyerror (char const *);
- static int yylex (void);
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
static int parent_rhs_before_value = 0;
static int merged_value = 0;
static int parent_rhs_after_value = 0;
@@ -1020,21 +1004,10 @@ merge (YYSTYPE s1, YYSTYPE s2)
return dummy;
}
-static void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
-static int
-yylex (void)
-{
- static int const input[] = { PARENT_RHS_AFTER, 0 };
- static const int *inputp = input;
- if (*inputp == PARENT_RHS_AFTER)
- parent_rhs_after_value = 1;
- return *inputp++;
-}
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE([{ PARENT_RHS_AFTER, 0 }],
+ [if (res == PARENT_RHS_AFTER)
+ parent_rhs_after_value = 1;])[
int
main (void)
@@ -1042,41 +1015,44 @@ main (void)
int exit_status = yyparse ();
if (parent_rhs_before_value)
{
- fprintf (stderr, "`parent_rhs_before' destructor not called.\n");
+ fprintf (stderr, "'parent_rhs_before' destructor not called.\n");
exit_status = 1;
}
if (merged_value)
{
- fprintf (stderr, "`merged' destructor not called.\n");
+ fprintf (stderr, "'merged' destructor not called.\n");
exit_status = 1;
}
if (parent_rhs_after_value)
{
- fprintf (stderr, "`PARENT_RHS_AFTER' destructor not called.\n");
+ fprintf (stderr, "'PARENT_RHS_AFTER' destructor not called.\n");
exit_status = 1;
}
return exit_status;
}
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr12.c glr-regr12.y]], 0, [],
-[glr-regr12.y: conflicts: 1 shift/reduce, 1 reduce/reduce
-])
+AT_BISON_CHECK([[-o glr-regr12.c glr-regr12.y]], 0, [],
+[[glr-regr12.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
+glr-regr12.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr12])
-AT_CHECK([[./glr-regr12]], 0, [], [])
+AT_PARSER_CHECK([[./glr-regr12]], 0, [], [])
AT_CLEANUP
## ------------------------------------------------------------------------- ##
-## Incorrect lookahead during deterministic GLR. See ##
+## Incorrect lookahead during deterministic GLR. See ##
## and ##
## . ##
## ------------------------------------------------------------------------- ##
AT_SETUP([Incorrect lookahead during deterministic GLR])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr13.y],
[[
/* Tests:
@@ -1088,8 +1064,9 @@ AT_DATA_GRAMMAR([glr-regr13.y],
%{
#include
- static void yyerror (char const *);
- static int yylex (void);
+ #include
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
static void print_lookahead (char const *);
#define USE(value)
%}
@@ -1140,22 +1117,9 @@ change_lookahead:
%%
-static void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
-static int
-yylex (void)
-{
- static char const *input = "ab";
- static int i = 0;
- yylloc.first_line = yylloc.last_line = 1;
- yylloc.first_column = yylloc.last_column = i + 1;
- yylval.value = input[i] + 'A' - 'a';
- return input[i++];
-}
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE(["ab"],
+ [yylval.value = res + 'A' - 'a'])[
static void
print_lookahead (char const *reduction)
@@ -1169,10 +1133,10 @@ print_lookahead (char const *reduction)
{
printf ("'%c', yylval='", yychar);
if (yylval.value > ' ')
- printf ("%c", yylval.value);
+ printf ("%c", yylval.value);
printf ("', yylloc=(%d,%d),(%d,%d)",
- yylloc.first_line, yylloc.first_column,
- yylloc.last_line, yylloc.last_column);
+ yylloc.first_line, yylloc.first_column,
+ yylloc.last_line, yylloc.last_column);
}
printf ("\n");
}
@@ -1185,11 +1149,12 @@ main (void)
return yyparse ();
}
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr13.c glr-regr13.y]], 0, [], [])
+AT_BISON_CHECK([[-o glr-regr13.c glr-regr13.y]], 0, [], [])
AT_COMPILE([glr-regr13])
-AT_CHECK([[./glr-regr13]], 0,
+AT_PARSER_CHECK([[./glr-regr13]], 0,
[defstate_init <- empty string:
yychar=YYEMPTY
nondefstate <- empty string:
@@ -1205,12 +1170,13 @@ start <- defstate_init defstate_shift 'b':
AT_CLEANUP
-## ------------------------------------------------------------------------- ##
-## Incorrect lookahead during nondeterministic GLR. ##
-## ------------------------------------------------------------------------- ##
+## ------------------------------------------------- ##
+## Incorrect lookahead during nondeterministic GLR. ##
+## ------------------------------------------------- ##
AT_SETUP([Incorrect lookahead during nondeterministic GLR])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr14.y],
[[
/* Tests:
@@ -1235,9 +1201,11 @@ AT_DATA_GRAMMAR([glr-regr14.y],
%union { char value; }
%{
+ #include
#include
- static void yyerror (char const *);
- static int yylex (void);
+ #include
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
static void print_lookahead (char const *);
static char merge (union YYSTYPE, union YYSTYPE);
#define USE(value)
@@ -1265,7 +1233,7 @@ merge:
| conflict defstate_look 'a' nonconflict2 'b' defstate_shift %dprec 2 {
USE ($3); USE ($5);
print_lookahead ("merge <- conflict defstate_look 'a' nonconflict2 'b'"
- " defstate_shift");
+ " defstate_shift");
}
;
@@ -1312,7 +1280,7 @@ alt1:
USE ($1);
if (yychar != 'd' && yychar != YYEOF)
{
- fprintf (stderr, "Incorrect lookahead during stack explosion.\n");
+ fprintf (stderr, "Incorrect lookahead during stack explosion.\n");
}
}
;
@@ -1321,7 +1289,7 @@ alt2:
USE ($1);
if (yychar != 'd' && yychar != YYEOF)
{
- fprintf (stderr, "Incorrect lookahead during stack explosion.\n");
+ fprintf (stderr, "Incorrect lookahead during stack explosion.\n");
}
}
;
@@ -1330,7 +1298,7 @@ alt3:
USE ($1);
if (yychar != 'd' && yychar != YYEOF)
{
- fprintf (stderr, "Incorrect lookahead during stack explosion.\n");
+ fprintf (stderr, "Incorrect lookahead during stack explosion.\n");
}
}
;
@@ -1338,29 +1306,25 @@ no_look:
{
if (yychar != YYEMPTY)
{
- fprintf (stderr,
- "Found lookahead where shouldn't during stack explosion.\n");
+ fprintf (stderr,
+ "Found lookahead where shouldn't during stack explosion.\n");
}
}
;
%%
-static void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
+]AT_YYERROR_DEFINE[
static int
yylex (void)
{
- static char const *input = "abcdddd";
- static int i = 0;
+ static char const input[] = "abcdddd";
+ static size_t toknum;
+ assert (toknum < sizeof input);
yylloc.first_line = yylloc.last_line = 1;
- yylloc.first_column = yylloc.last_column = i + 1;
- yylval.value = input[i] + 'A' - 'a';
- return input[i++];
+ yylloc.first_column = yylloc.last_column = toknum + 1;
+ yylval.value = input[toknum] + 'A' - 'a';
+ return input[toknum++];
}
static void
@@ -1375,10 +1339,10 @@ print_lookahead (char const *reduction)
{
printf ("'%c', yylval='", yychar);
if (yylval.value > ' ')
- printf ("%c", yylval.value);
+ printf ("%c", yylval.value);
printf ("', yylloc=(%d,%d),(%d,%d)",
- yylloc.first_line, yylloc.first_column,
- yylloc.last_line, yylloc.last_column);
+ yylloc.first_line, yylloc.first_column,
+ yylloc.last_line, yylloc.last_column);
}
printf ("\n");
}
@@ -1398,13 +1362,14 @@ main (void)
return yyparse ();
}
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr14.c glr-regr14.y]], 0, [],
-[glr-regr14.y: conflicts: 3 reduce/reduce
-])
+AT_BISON_CHECK([[-o glr-regr14.c glr-regr14.y]], 0, [],
+[[glr-regr14.y: warning: 3 reduce/reduce conflicts [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr14])
-AT_CHECK([[./glr-regr14]], 0,
+AT_PARSER_CHECK([[./glr-regr14]], 0,
[conflict <- empty string:
yychar='a', yylval='A', yylloc=(1,1),(1,1)
defstate_look <- empty string:
@@ -1422,12 +1387,13 @@ start <- merge 'c' stack_explosion:
AT_CLEANUP
-## ------------------------------------------------------------------------- ##
-## Leaked semantic values when reporting ambiguity. ##
-## ------------------------------------------------------------------------- ##
+## ------------------------------------------------- ##
+## Leaked semantic values when reporting ambiguity. ##
+## ------------------------------------------------- ##
AT_SETUP([Leaked semantic values when reporting ambiguity])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr15.y],
[[
%glr-parser
@@ -1435,8 +1401,8 @@ AT_DATA_GRAMMAR([glr-regr15.y],
%{
# include
- static void yyerror (char const *);
- static int yylex (void);
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
static int parent_rhs_before_value = 0;
# define USE(val)
%}
@@ -1474,18 +1440,8 @@ ambiguity1: ;
ambiguity2: ;
%%
-
-static void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
-static int
-yylex (void)
-{
- return 0;
-}
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE[
int
main (void)
@@ -1493,30 +1449,33 @@ main (void)
int exit_status = yyparse () != 1;
if (parent_rhs_before_value)
{
- fprintf (stderr, "`parent_rhs_before' destructor not called.\n");
+ fprintf (stderr, "'parent_rhs_before' destructor not called.\n");
exit_status = 1;
}
return exit_status;
}
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr15.c glr-regr15.y]], 0, [],
-[glr-regr15.y: conflicts: 2 reduce/reduce
-])
+AT_BISON_CHECK([[-o glr-regr15.c glr-regr15.y]], 0, [],
+[[glr-regr15.y: warning: 2 reduce/reduce conflicts [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr15])
-AT_CHECK([[./glr-regr15]], 0, [],
+AT_PARSER_CHECK([[./glr-regr15]], 0, [],
[syntax is ambiguous
])
AT_CLEANUP
-## ------------------------------------------------------------------------- ##
-## Leaked lookahead after nondeterministic parse syntax error. ##
-## ------------------------------------------------------------------------- ##
+## ------------------------------------------------------------ ##
+## Leaked lookahead after nondeterministic parse syntax error. ##
+## ------------------------------------------------------------ ##
AT_SETUP([Leaked lookahead after nondeterministic parse syntax error])
+
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([glr-regr16.y],
[[
%glr-parser
@@ -1524,8 +1483,9 @@ AT_DATA_GRAMMAR([glr-regr16.y],
%{
# include
- static void yyerror (char const *);
- static int yylex (void);
+# include
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
static int lookahead_value = 0;
# define USE(val)
%}
@@ -1538,20 +1498,10 @@ alt2: ;
%%
-static void
-yyerror (char const *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
-static int
-yylex (void)
-{
- static char const *input = "ab";
- if (*input == 'b')
- lookahead_value = 1;
- return *input++;
-}
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE(["ab"],
+ [if (res == 'b')
+ lookahead_value = 1])[
int
main (void)
@@ -1565,45 +1515,42 @@ main (void)
return exit_status;
}
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr16.c glr-regr16.y]], 0, [],
-[glr-regr16.y: conflicts: 1 reduce/reduce
-])
+AT_BISON_CHECK([[-o glr-regr16.c glr-regr16.y]], 0, [],
+[[glr-regr16.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr16])
-AT_CHECK([[./glr-regr16]], 0, [],
+AT_PARSER_CHECK([[./glr-regr16]], 0, [],
[syntax error
])
AT_CLEANUP
-## ------------------------------------------------------------------------- ##
-## Uninitialized location when reporting ambiguity. ##
-## ------------------------------------------------------------------------- ##
+## ------------------------------------------------- ##
+## Uninitialized location when reporting ambiguity. ##
+## ------------------------------------------------- ##
AT_SETUP([Uninitialized location when reporting ambiguity])
+
+AT_BISON_OPTION_PUSHDEFS([%glr-parser %locations %define api.pure])
+
AT_DATA_GRAMMAR([glr-regr17.y],
[[
%glr-parser
%locations
-%pure-parser
+%define api.pure
%error-verbose
%union { int dummy; }
%{
- static void yyerror (YYLTYPE *, char const *);
- static int yylex (YYSTYPE *, YYLTYPE *);
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
%}
-%initial-action {
- @$.first_line = 1;
- @$.first_column = 1;
- @$.last_line = 1;
- @$.last_column = 1;
-}
-
%%
/* Tests the case of an empty RHS that has inherited the location of the
@@ -1624,40 +1571,211 @@ empty1: ;
empty2: ;
%%
+# include
-static void
-yyerror (YYLTYPE *locp, char const *msg)
-{
- fprintf (stderr, "Error at %d.%d-%d.%d: %s.\n", locp->first_line,
- locp->first_column, locp->last_line, locp->last_column, msg);
-}
-
+]AT_YYERROR_DEFINE[
static int
yylex (YYSTYPE *lvalp, YYLTYPE *llocp)
{
static char const input[] = "ab";
- static char const *inputp = input;
+ static size_t toknum;
+ assert (toknum < sizeof input);
lvalp->dummy = 0;
llocp->first_line = llocp->last_line = 2;
- llocp->first_column = inputp - input + 1;
+ llocp->first_column = toknum + 1;
llocp->last_column = llocp->first_column + 1;
- return *inputp++;
+ return input[toknum++];
}
-int
-main (void)
-{
- return yyparse () != 1;
-}
+]AT_MAIN_DEFINE[
]])
+AT_BISON_OPTION_POPDEFS
-AT_CHECK([[bison -o glr-regr17.c glr-regr17.y]], 0, [],
-[glr-regr17.y: conflicts: 3 reduce/reduce
-])
+AT_BISON_CHECK([[-o glr-regr17.c glr-regr17.y]], 0, [],
+[[glr-regr17.y: warning: 3 reduce/reduce conflicts [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr17])
-AT_CHECK([[./glr-regr17]], 0, [],
-[Error at 1.1-2.3: syntax is ambiguous.
+AT_PARSER_CHECK([[./glr-regr17]], 1, [],
+[1.1-2.2: syntax is ambiguous
])
AT_CLEANUP
+
+
+## ------------------------------------------------------------- ##
+## Missed %merge type warnings when LHS type is declared later. ##
+## ------------------------------------------------------------- ##
+
+AT_SETUP([Missed %merge type warnings when LHS type is declared later])
+
+AT_BISON_OPTION_PUSHDEFS
+AT_DATA_GRAMMAR([glr-regr18.y],
+[[%glr-parser
+
+%{
+ #include
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
+%}
+
+%union {
+ int type1;
+ int type2;
+ int type3;
+}
+
+%%
+
+sym1: sym2 %merge { $$ = $1; } ;
+sym2: sym3 %merge { $$ = $1; } ;
+sym3: %merge { $$ = 0; } ;
+
+%type sym1;
+%type sym2;
+%type sym3;
+
+%%
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE[
+]AT_MAIN_DEFINE[
+]])
+AT_BISON_OPTION_POPDEFS
+
+AT_BISON_CHECK([[-o glr-regr18.c glr-regr18.y]], 1, [],
+[[glr-regr18.y:28.18-24: error: result type clash on merge function 'merge': !=
+glr-regr18.y:27.18-24: previous declaration
+glr-regr18.y:29.13-19: error: result type clash on merge function 'merge': !=
+glr-regr18.y:28.18-24: previous declaration
+]])
+
+AT_CLEANUP
+
+
+## ------------------- ##
+## Ambiguity reports. ##
+## ------------------- ##
+
+AT_SETUP([Ambiguity reports])
+
+AT_BISON_OPTION_PUSHDEFS([%debug])
+AT_DATA_GRAMMAR([input.y],
+[[
+%{
+ #include
+ #include
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
+%}
+
+%debug
+%glr-parser
+
+%%
+start:
+ 'a' b 'c' d
+| 'a' b 'c' d
+;
+b: 'b';
+d: /* nada. */;
+%%
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE(["abc"])[
+]AT_MAIN_DEFINE[
+]])
+AT_BISON_OPTION_POPDEFS
+
+AT_BISON_CHECK([[-o input.c input.y]], 0, [],
+[[input.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
+AT_COMPILE([input])
+
+AT_PARSER_CHECK([[./input --debug]], 1, [],
+[Starting parse
+Entering state 0
+Reading a token: Next token is token 'a' ()
+Shifting token 'a' ()
+Entering state 1
+Reading a token: Next token is token 'b' ()
+Shifting token 'b' ()
+Entering state 3
+Reducing stack 0 by rule 3 (line 27):
+ $1 = token 'b' ()
+-> $$ = nterm b ()
+Entering state 4
+Reading a token: Next token is token 'c' ()
+Shifting token 'c' ()
+Entering state 6
+Reducing stack 0 by rule 4 (line 28):
+-> $$ = nterm d ()
+Entering state 7
+Reading a token: Now at end of input.
+Stack 0 Entering state 7
+Now at end of input.
+Splitting off stack 1 from 0.
+Reduced stack 1 by rule #2; action deferred. Now in state 2.
+Stack 1 Entering state 2
+Now at end of input.
+Reduced stack 0 by rule #1; action deferred. Now in state 2.
+Merging stack 0 into stack 1.
+Stack 1 Entering state 2
+Now at end of input.
+Removing dead stacks.
+Rename stack 1 -> 0.
+On stack 0, shifting token $end ()
+Stack 0 now in state #5
+Ambiguity detected.
+Option 1,
+ start ->
+ 'a'
+ b
+ 'c'
+ d
+
+Option 2,
+ start ->
+ 'a'
+ b
+ 'c'
+ d
+
+syntax is ambiguous
+Cleanup: popping token $end ()
+Cleanup: popping unresolved nterm start ()
+Cleanup: popping nterm d ()
+Cleanup: popping token 'c' ()
+Cleanup: popping nterm b ()
+Cleanup: popping token 'a' ()
+])
+
+AT_CLEANUP
+
+
+## ----------------------------------------------------------------- ##
+## Predicates. ##
+## ##
+## http://lists.gnu.org/archive/html/bug-bison/2013-10/msg00004.html ##
+## ----------------------------------------------------------------- ##
+
+AT_SETUP([Predicates])
+
+# FIXME: We need genuine test cases with uses of %?.
+
+AT_DATA_GRAMMAR([input.y],
+[[%glr-parser
+%expect-rr 1
+%%
+// Exercise "%?{...}" and "%? {...}".
+widget:
+ %? {new_syntax} "widget" id new_args { $$ = f($3, $4); }
+| %?{!new_syntax} "widget" id old_args { $$ = f($3, $4); }
+;
+id:;
+new_args:;
+old_args:;
+%%
+]])
+
+AT_BISON_CHECK([[input.y]])
+
+AT_CLEANUP