1 files changed, 2 insertions, 0 deletions
diff --git a/pp.c b/pp.c
index 8a7632af39..2958fba4bf 100644
--- a/pp.c
+++ b/pp.c
@@ -3111,6 +3111,8 @@ PP(pp_substr)
 		sv_upgrade(TARG, SVt_PVLV);
 		sv_magic(TARG, Nullsv, PERL_MAGIC_substr, Nullch, 0);
 	    }
+	    else
+		(void)SvOK_off(TARG);
 
 	    LvTYPE(TARG) = 'x';
 	    if (LvTARG(TARG) != sv) {