fprintf(stderr,"error: %s\n",s);
}
-FILE *input = NULL;
+FILE *input = YY_NULL;
int P[] = { P1, P2 };
int O[] = { O1, O2 };
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);
+ fprintf (stderr, "%d.%d-%d.%d: %s.\n", locp->first_line,
+ locp->first_column, locp->last_line, locp->last_column, msg);
}
static int
AT_COMPILE([glr-regr17])
AT_PARSER_CHECK([[./glr-regr17]], 0, [],
-[Error at 1.1-2.3: syntax is ambiguous.
+[1.1-2.3: syntax is ambiguous.
])
AT_CLEANUP
]])
AT_BISON_CHECK([[-o glr-regr18.c glr-regr18.y]], 1, [],
-[glr-regr18.y:26.18-24: result type clash on merge function `merge': <type2> != <type1>
+[glr-regr18.y:26.18-24: result type clash on merge function 'merge': <type2> != <type1>
glr-regr18.y:25.18-24: previous declaration
-glr-regr18.y:27.13-19: result type clash on merge function `merge': <type3> != <type2>
+glr-regr18.y:27.13-19: result type clash on merge function 'merge': <type3> != <type2>
glr-regr18.y:26.18-24: previous declaration
])
AT_CLEANUP
+
+
+## ------------------- ##
+## Ambiguity reports. ##
+## ------------------- ##
+
+AT_SETUP([Ambiguity reports])
+
+AT_DATA_GRAMMAR([input.y],
+[[
+%{
+ #include <stdio.h>
+ #include <stdlib.h>
+ static void yyerror (char const *);
+ static int yylex (void);
+%}
+
+%debug
+%glr-parser
+
+%%
+start:
+ 'a' b 'c' d
+| 'a' b 'c' d
+;
+b: 'b';
+d: /* nada. */;
+%%
+
+static int
+yylex (void)
+{
+ static char const input[] = "abc";
+ static size_t toknum;
+ if (! (toknum < sizeof input))
+ abort ();
+ return input[toknum++];
+}
+
+static void
+yyerror (char const *msg)
+{
+ fprintf (stderr, "%s\n", msg);
+}
+
+int
+main (void)
+{
+ yydebug = 1;
+ return !!yyparse ();
+}
+]])
+
+AT_BISON_CHECK([[-o input.c input.y]], 0, [],
+[input.y: conflicts: 1 reduce/reduce
+])
+AT_COMPILE([input])
+
+AT_PARSER_CHECK([[./input]], 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 25):
+ $1 = token 'b' ()
+-> $$ = nterm b ()
+Entering state 4
+Reading a token: Next token is token 'c' ()
+Shifting token 'c' ()
+Entering state 6
+Reducing stack 0 by rule 4 (line 26):
+-> $$ = 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 -> <Rule 1, tokens 1 .. 3>
+ 'a' <tokens 1 .. 1>
+ b <tokens 2 .. 2>
+ 'c' <tokens 3 .. 3>
+ d <empty>
+
+Option 2,
+ start -> <Rule 2, tokens 1 .. 3>
+ 'a' <tokens 1 .. 1>
+ b <tokens 2 .. 2>
+ 'c' <tokens 3 .. 3>
+ d <empty>
+
+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