X-Git-Url: https://perl5.git.perl.org/perl5.git/blobdiff_plain/68853529b82cedc7fc5774cbdb57734af389f541..8f78557a961555c7d3a0f903d990f4f78b07624a:/sv.c

diff --git a/sv.c b/sv.c
index 5e61449..40d99cb 100644
--- a/sv.c
+++ b/sv.c
@@ -4497,14 +4497,17 @@ Perl_sv_force_normal_flags(pTHX_ register SV *sv, U32 flags)
     if (SvREADONLY(sv)) {
 	if (SvFAKE(sv)) {
 	    char *pvx = SvPVX(sv);
+	    int is_utf8 = SvUTF8(sv);
 	    STRLEN len = SvCUR(sv);
             U32 hash   = SvUVX(sv);
 	    SvFAKE_off(sv);
 	    SvREADONLY_off(sv);
+            SvPVX(sv) = 0;
+            SvLEN(sv) = 0;
 	    SvGROW(sv, len + 1);
 	    Move(pvx,SvPVX(sv),len,char);
 	    *SvEND(sv) = '\0';
-	    unsharepvn(pvx, SvUTF8(sv) ? -(I32)len : len, hash);
+	    unsharepvn(pvx, is_utf8 ? -(I32)len : len, hash);
 	}
 	else if (IN_PERL_RUNTIME)
 	    Perl_croak(aTHX_ PL_no_modify);
@@ -5732,10 +5735,8 @@ S_utf8_mg_pos_init(pTHX_ SV *sv, MAGIC **mgp, STRLEN **cachep, I32 i, I32 *offse
     bool found = FALSE; 
 
     if (SvMAGICAL(sv) && !SvREADONLY(sv)) {
-	if (!*mgp) {
-	    sv_magic(sv, 0, PERL_MAGIC_utf8, 0, 0);
-	    *mgp = mg_find(sv, PERL_MAGIC_utf8);
-	}
+	if (!*mgp)
+	    *mgp = sv_magicext(sv, 0, PERL_MAGIC_utf8, &PL_vtbl_utf8, 0, 0);
 	assert(*mgp);
 
 	if ((*mgp)->mg_ptr)
@@ -5828,6 +5829,12 @@ S_utf8_mg_pos(pTHX_ SV *sv, MAGIC **mgp, STRLEN **cachep, I32 i, I32 *offsetp, I
 		      /* Update the cache. */
 		      (*cachep)[i]   = (STRLEN)uoff;
 		      (*cachep)[i+1] = p - start;
+
+		      /* Drop the stale "length" cache */
+		      if (i == 0) {
+			  (*cachep)[2] = 0;
+			  (*cachep)[3] = 0;
+		      }
  
 		      found = TRUE;
 		 }
@@ -6053,7 +6060,8 @@ Perl_sv_pos_b2u(pTHX_ register SV* sv, I32* offsetp)
 	    assert(mg);
 
 	    if (!mg->mg_ptr) {
-		Newz(0, cache, PERL_MAGIC_UTF8_CACHESIZE * 2, STRLEN);
+		mg->mg_len = PERL_MAGIC_UTF8_CACHESIZE * 2;
+		Newz(0, cache, mg->mg_len, STRLEN);
 		mg->mg_ptr = (char *) cache;
 	    }
 	    assert(cache);