Avoid potentially empty struct.

[p5sagit/p5-mst-13.2.git] / sv.c

diff --git a/sv.c b/sv.c
index 0350bae..13b548b 100644 (file)
--- a/sv.c
+++ b/sv.c
@@ -3192,14 +3192,16 @@ would lose the UTF-8'ness of the PV.
 void
 Perl_sv_copypv(pTHX_ SV *dsv, register SV *ssv)
 {
-    SV *tmpsv = sv_newmortal();
+    SV *tmpsv;
 
-    if ( SvTHINKFIRST(ssv) && SvROK(ssv) && SvAMAGIC(ssv) ) {
-       tmpsv = AMG_CALLun(ssv,string);
+    if ( SvTHINKFIRST(ssv) && SvROK(ssv) && SvAMAGIC(ssv) && 
+        (tmpsv = AMG_CALLun(ssv,string))) {
        if (SvTYPE(tmpsv) != SVt_RV || (SvRV(tmpsv) != SvRV(ssv))) {
            SvSetSV(dsv,tmpsv);
            return;
        }
+    } else {
+        tmpsv = sv_newmortal();
     }
     {
        STRLEN len;
@@ -4466,7 +4468,9 @@ Perl_sv_magicext(pTHX_ SV* sv, SV* obj, int how, MGVTBL *vtable,
        (SvTYPE(obj) == SVt_PVGV &&
            (GvSV(obj) == sv || GvHV(obj) == (HV*)sv || GvAV(obj) == (AV*)sv ||
            GvCV(obj) == (CV*)sv || GvIOp(obj) == (IO*)sv ||
-           GvFORM(obj) == (CV*)sv)))
+           GvFORM(obj) == (CV*)sv)) ||
+       (how == PERL_MAGIC_tiedscalar &&
+           SvROK(obj) && (SvRV(obj) == sv || GvIO(SvRV(obj)) == (IO*)sv)))
     {
        mg->mg_obj = obj;
     }
@@ -6334,7 +6338,7 @@ Perl_newSVpvn_share(pTHX_ const char *src, I32 len, U32 hash)
        len = tmplen;
     }
     if (!hash)
-       PERL_HASH(hash, src, len);
+       PERL_HASH(hash, (U8*)src, len);
     new_SV(sv);
     sv_upgrade(sv, SVt_PVIV);
     SvPVX(sv) = sharepvn(src, is_utf8?-len:len, hash);
@@ -6594,8 +6598,14 @@ Perl_sv_reset(pTHX_ register char *s, HV *stash)
                if (GvHV(gv) && !HvNAME(GvHV(gv))) {
                    hv_clear(GvHV(gv));
 #ifdef USE_ENVIRON_ARRAY
-                   if (gv == PL_envgv)
+                   if (gv == PL_envgv
+#  ifdef USE_ITHREADS
+                       && PL_curinterp == aTHX
+#  endif
+                   )
+                   {
                        environ[0] = Nullch;
+                   }
 #endif
                }
            }
@@ -7290,9 +7300,6 @@ Perl_sv_bless(pTHX_ SV *sv, HV *stash)
 }
 
 /* Downgrades a PVGV to a PVMG.
- *
- * XXX This function doesn't actually appear to be used anywhere
- * DAPM 15-Jun-01
  */
 
 STATIC void