(Retracted by #8264)

(Fixed by #8260.)

sv_catsv() needs one more byte space than seems reasonable.
(for join() and PERL_DESTRUCT_LEVEL=2, built with debugging).
Curiouser and curiouser.

p4raw-id: //depot/perl@8251

diff --git a/sv.c b/sv.c
index 97ee2ad..b43c066 100644 (file)
--- a/sv.c
+++ b/sv.c
@@ -3768,8 +3768,6 @@ Perl_sv_catsv(pTHX_ SV *dsv, register SV *ssv)
            bool sutf8 = DO_UTF8(ssv);
            
            if (dutf8 != sutf8) {
-               char *s = spv;
-               char *send = s + slen;
                STRLEN dlen;
                char *dpv;
                char *d;
@@ -3780,20 +3778,28 @@ Perl_sv_catsv(pTHX_ SV *dsv, register SV *ssv)
                    sv_utf8_upgrade(dsv);
                dpv = SvPV(dsv, dlen);
                /* Overguestimate on the slen. */
-               SvGROW(dsv, dlen + (sutf8 ? 2 * slen : slen) + 1);
+               /* (Why +2 and not +1 is needed?
+                * (Try PERL_DESTRUCT_LEVEL=2 ./perl t/op/join.t)
+                * Can't figure out right now. --jhi) */
+               SvGROW(dsv, dlen + (sutf8 ? 2 * slen : slen) + 2);
                d = dpv + dlen;
                if (dutf8) /* && !sutf8 */ {
+                   char *s = spv;
+                   char *send = s + slen;
+
                    while (s < send) {
-                       if (UTF8_IS_ASCII(*s))
-                           *d++ = *s++;
+                       U8 c = *s++;
+
+                       if (UTF8_IS_ASCII(c))
+                           *d++ = c;
                        else {
-                           *d++ = UTF8_EIGHT_BIT_HI(*s);
-                           *d++ = UTF8_EIGHT_BIT_LO(*s);
-                           s += 2;
+                           *d++ = UTF8_EIGHT_BIT_HI(c);
+                           *d++ = UTF8_EIGHT_BIT_LO(c);
+                           s++; /* skip the low byte */
                        }
                    }
                    SvCUR(dsv) += s - spv;
-                   *SvEND(dsv) = 0;
+                   *d = 0;
                }
                else /* !dutf8 (was) && sutf8 */ {
                    sv_catpvn(dsv, spv, slen);