start:
alt1 %dprec 1
| alt2 %dprec 2
- ;
+ ;
alt1:
PARENT_RHS_AFTER {
static int
yylex (void)
{
- static const char *input = "ab";
+ static char const *input = "ab";
if (*input == 'b')
lookahead_value = 1;
return *input++;
])
AT_CLEANUP
+
+
+## ------------------------------------------------------------------------- ##
+## Uninitialized location when reporting ambiguity. ##
+## ------------------------------------------------------------------------- ##
+
+AT_SETUP([Uninitialized location when reporting ambiguity])
+AT_DATA_GRAMMAR([glr-regr17.y],
+[[
+%glr-parser
+%locations
+%pure-parser
+%error-verbose
+
+%union { int dummy; }
+
+%{
+ static void yyerror (YYLTYPE *, char const *);
+ static int yylex (YYSTYPE *, YYLTYPE *);
+%}
+
+%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
+ previous nonterminal, which is unresolved. That location is reported as the
+ last position of the ambiguity. */
+start: ambig1 empty1 | ambig2 empty2 ;
+
+/* Tests multiple levels of yyresolveLocations recursion. */
+ambig1: sub_ambig1 | sub_ambig2 ;
+ambig2: sub_ambig1 | sub_ambig2 ;
+
+/* Tests the case of a non-empty RHS as well as the case of an empty RHS that
+ has inherited the initial location. The empty RHS's location is reported as
+ the first position in the ambiguity. */
+sub_ambig1: empty1 'a' 'b' ;
+sub_ambig2: empty2 'a' 'b' ;
+empty1: ;
+empty2: ;
+
+%%
+
+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);
+}
+
+static int
+yylex (YYSTYPE *lvalp, YYLTYPE *llocp)
+{
+ static char const input[] = "ab";
+ static char const *inputp = input;
+ lvalp->dummy = 0;
+ llocp->first_line = llocp->last_line = 2;
+ llocp->first_column = inputp - input + 1;
+ llocp->last_column = llocp->first_column + 1;
+ return *inputp++;
+}
+
+int
+main (void)
+{
+ return yyparse () != 1;
+}
+]])
+
+AT_CHECK([[bison -o glr-regr17.c glr-regr17.y]], 0, [],
+[glr-regr17.y: conflicts: 3 reduce/reduce
+])
+AT_COMPILE([glr-regr17])
+
+AT_CHECK([[./glr-regr17]], 0, [],
+[Error at 1.1-2.3: syntax is ambiguous.
+])
+
+AT_CLEANUP