Salvage bits and pieces from the experimental 'utf8 everywhere'

patch: rename HINT_BYTE and IN_BYTE to HINT_BYTES and IN_BYTES
to match the pragma name; various robustness cleanups.

p4raw-id: //depot/perl@10339

1 files changed, 4 insertions, 2 deletions

diff --git a/mg.c b/mg.c
index 4b6d25de18..b9a027e476 100644
--- a/mg.c
+++ b/mg.c
@@ -375,9 +375,11 @@ Perl_magic_regdatum_get(pTHX_ SV *sv, MAGIC *mg)
 		
 		if (i > 0 && DO_UTF8(PL_reg_sv)) {
 		    char *b = rx->subbeg;
-		    i = Perl_utf8_length(aTHX_ (U8*)b, (U8*)(b+i));
+		    if (b)
+		        i = Perl_utf8_length(aTHX_ (U8*)b, (U8*)(b+i));
 		}
-		sv_setiv(sv,i);
+
+		sv_setiv(sv, i);
 	    }
     }
     return 0;