Add support for Bison versions up to 3.7

This requires copying the `YY_CAST` and `YY_ATTRIBUTE_UNUSED` macros
from the generated code, and extracting the `yysymbol_kind_t` enum if
it's defined.

We must also handle token type names with escaped double-quotes in
them, since it now names the `YYEOF` and `YYUNDEF` tokens `"end of
file"` and `"invalid token"` instead of `$end` and `$undefined`,
respectively.

1 files changed, 18 insertions, 0 deletions

diff --git a/perly.c b/perly.c
index 2b152c7d87..091371937d 100644
--- a/perly.c
+++ b/perly.c
@@ -53,6 +53,24 @@ typedef signed char yysigned_char;
 # define YY_NULLPTR NULL
 #endif
 
+#ifndef YY_CAST
+# ifdef __cplusplus
+#  define YY_CAST(Type, Val) static_cast<Type> (Val)
+#  define YY_REINTERPRET_CAST(Type, Val) reinterpret_cast<Type> (Val)
+# else
+#  define YY_CAST(Type, Val) ((Type) (Val))
+#  define YY_REINTERPRET_CAST(Type, Val) ((Type) (Val))
+# endif
+#endif
+
+#ifndef YY_ATTRIBUTE_UNUSED
+# if defined __GNUC__ && 2 < __GNUC__ + (7 <= __GNUC_MINOR__)
+#  define YY_ATTRIBUTE_UNUSED __attribute__ ((__unused__))
+# else
+#  define YY_ATTRIBUTE_UNUSED
+# endif
+#endif
+
 /* contains all the parser state tables; auto-generated from perly.y */
 #include "perly.tab"