1 files changed, 1 insertions, 0 deletions
diff --git a/sv.c b/sv.c
index bf8d503c42..7844c498c5 100644
--- a/sv.c
+++ b/sv.c
@@ -5136,6 +5136,7 @@ Perl_sv_clear(pTHX_ register SV *sv)
 
     assert(sv);
     assert(SvREFCNT(sv) == 0);
+    assert(SvTYPE(sv) != SVTYPEMASK);
 
     if (type <= SVt_IV) {
 	/* See the comment in sv.h about the collusion between this early