diff options
| -rw-r--r-- | grammar.y.in | 22 |
1 files changed, 16 insertions, 6 deletions
diff --git a/grammar.y.in b/grammar.y.in index 6a97cbc0..8617f90b 100644 --- a/grammar.y.in +++ b/grammar.y.in @@ -110,21 +110,31 @@ struct rtentry; #include "os-proto.h" #endif -#ifdef YYBYACC +/* + * Work around some bugs in Berkeley YACC prior to the 2017-07-09 + * release. + * + * The 2005-05-05 release was the first one to define YYPATCH, so + * we treat any release that either 1) doesn't define YYPATCH or + * 2) defines it to a value < 20170709 as being buggy. + */ +#if defined(YYBYACC) && (!defined(YYPATCH) || YYPATCH < 20170709) /* * Both Berkeley YACC and Bison define yydebug (under whatever name * it has) as a global, but Bison does so only if YYDEBUG is defined. - * Berkeley YACC define it even if YYDEBUG isn't defined; declare it - * here to suppress a warning. + * Berkeley YACC, prior to the 2017-07-09 release, defines it even if + * YYDEBUG isn't defined; declare it here to suppress a warning. The + * 2017-07-09 release fixes that. */ #if !defined(YYDEBUG) extern int yydebug; #endif /* - * In Berkeley YACC, yynerrs (under whatever name it has) is global, - * even if it's building a reentrant parser. In Bison, it's local - * in reentrant parsers. + * In Berkeley YACC, prior to the 2017-07-09 release, yynerrs (under + * whatever name it has) is global, even if it's building a reentrant + * parser. In Bison, and in the Berkeley YACC 2017-07-09 release and + * later, it's local in reentrant parsers. * * Declare it to squelch a warning. */ |