marvin@smokie:~/projects/perl-git $ git diff
diff --git a/sv.c b/sv.c
index a53669a..280f064 100644
--- a/sv.c
+++ b/sv.c
@@ -3231,6 +3231,8 @@ Perl_sv_utf8_upgrade_flags_grow(pTHX_ register SV *const sv, const I32 flags, 
                if (extra) SvGROW(sv, SvCUR(sv) + extra);
                return len;
            }
+        } else if (SvGMAGICAL(sv) && mg_find(sv, PERL_MAGIC_sv)) {
+            ;
        } else {
            (void) SvPV_force(sv,len);
        }