Grow zero length scalars

diff --git a/sv.c b/sv.c
index 4b97e58..2bb6f11 100644 (file)
--- a/sv.c
+++ b/sv.c
@@ -3250,7 +3250,9 @@ Perl_sv_utf8_upgrade_flags_grow(pTHX_ register SV *const sv, const I32 flags, ST
        return SvCUR(sv);
     }
 
-    if (SvCUR(sv) > 0) { /* Assume Latin-1/EBCDIC */
+    if (SvCUR(sv) == 0) {
+       if (extra) SvGROW(sv, extra);
+    } else { /* Assume Latin-1/EBCDIC */
        /* This function could be much more efficient if we
         * had a FLAG in SVs to signal if there are any variant
         * chars in the PV.  Given that there isn't such a flag