[PATCH 5.6.0] warn on \8, \9

This patch enables the standard warning for 8, 9, _ as well as letters:

  Unrecognized escape \9 passed through at -e line 1.

Hugo
--- toke.c.old	Tue Mar 21 05:30:21 2000
+++ toke.c	Sat Apr 29 19:11:16 2000
@@ -1377,7 +1377,7 @@
 	    default:
 	        {
 		    dTHR;
-		    if (ckWARN(WARN_MISC) && isALPHA(*s))
+		    if (ckWARN(WARN_MISC) && isALNUM(*s))
 			Perl_warner(aTHX_ WARN_MISC, 
 			       "Unrecognized escape \\%c passed through",
 			       *s);

• [PATCH 5.6.0] warn on \8, \9 by Hugo