[perl #121255] Call set-magic when setting $DB::sub

Otherwise UTF8 length caches will not be reset, resulting in panicks
when ${^UTF8CACHE} is -1 or wrongs answers from length($DB::sub) when
${^UTF8CACHE} is 1.

1 files changed, 1 insertions, 0 deletions

diff --git a/util.c b/util.c
index 6dc39f0a49..5541ac9e14 100644
--- a/util.c
+++ b/util.c
@@ -5334,6 +5334,7 @@ Perl_get_db_sub(pTHX_ SV **svp, CV *cv)
 	(void)SvIOK_on(dbsv);
 	SvIV_set(dbsv, PTR2IV(cv));	/* Do it the quickest way  */
     }
+    SvSETMAGIC(dbsv);
     TAINT_IF(save_taint);
 #ifdef NO_TAINT_SUPPORT
     PERL_UNUSED_VAR(save_taint);