reader: reject rules on YYEOF
We crashed when rules were given on YYEOF.
Reported by Han Zheng.
Fixes https://github.com/akimd/bison/issues/92.
* src/reader.c (check_and_convert_grammar): Make sure YYEOF is not
an nterm.
* tests/input.at (Rule for YYEOF): New.
diff --git a/src/reader.c b/src/reader.c
index baa5d80..3d60ab3 100644
--- a/src/reader.c
+++ b/src/reader.c
@@ -954,6 +954,10 @@
if (!eoftoken)
{
eoftoken = symbol_get ("YYEOF", empty_loc);
+ if (eoftoken->content->class == nterm_sym)
+ complain (&eoftoken->location, complaint,
+ _("rule given for %s, which is a token"),
+ eoftoken->tag);
eoftoken->content->class = token_sym;
eoftoken->content->number = 0;
/* Value specified by POSIX. */
diff --git a/tests/input.at b/tests/input.at
index f76000b..5cacb06 100644
--- a/tests/input.at
+++ b/tests/input.at
@@ -1888,6 +1888,38 @@
AT_CLEANUP
+## ---------------- ##
+## Rule for YYEOF. ##
+## ---------------- ##
+
+AT_SETUP([Rule for YYEOF])
+
+# We crashed when rules were given on YYEOF.
+# https://github.com/akimd/bison/issues/92.
+
+AT_DATA([input1.y],
+[[%%
+start: YYEOF;
+YYEOF: 'x';
+]])
+
+AT_BISON_CHECK([input1.y], [1], [],
+[[input1.y:3.1-5: error: rule given for YYEOF, which is a token
+]])
+
+# This is ok, YYEOF is not special.
+AT_DATA([input2.y],
+[[%token MYEOF 0
+%%
+start: YYEOF;
+YYEOF: 'x';
+]])
+
+AT_BISON_CHECK([input2.y])
+
+AT_CLEANUP
+
+
## --------------------- ##
## %prec takes a token. ##
## --------------------- ##
