perldelta for 23695c073f41

[perl5.git] / pp_hot.c

diff --git a/pp_hot.c b/pp_hot.c
index 5a6f95c..223169b 100644 (file)
--- a/pp_hot.c
+++ b/pp_hot.c
@@ -284,8 +284,11 @@ PP(pp_concat)
     }
     else { /* $l .= $r   and   left == TARG */
        if (!SvOK(left)) {
-           if (left == right && ckWARN(WARN_UNINITIALIZED)) /* $l .= $l */
-               report_uninit(right);
+            if ((left == right                          /* $l .= $l */
+                 || (PL_op->op_private & OPpTARGET_MY)) /* $l = $l . $r */
+                && ckWARN(WARN_UNINITIALIZED)
+                )
+                report_uninit(left);
            sv_setpvs(left, "");
        }
         else {
@@ -2892,7 +2895,7 @@ PP(pp_subst)
     STRLEN slen;
     bool doutf8 = FALSE; /* whether replacement is in utf8 */
 #ifdef PERL_ANY_COW
-    bool is_cow;
+    bool was_cow;
 #endif
     SV *nsv = NULL;
     /* known replacement string? */
@@ -2911,9 +2914,8 @@ PP(pp_subst)
 
     SvGETMAGIC(TARG); /* must come before cow check */
 #ifdef PERL_ANY_COW
-    /* Awooga. Awooga. "bool" types that are actually char are dangerous,
-       because they make integers such as 256 "false".  */
-    is_cow = SvIsCOW(TARG) ? TRUE : FALSE;
+    /* note that a string might get converted to COW during matching */
+    was_cow = cBOOL(SvIsCOW(TARG));
 #endif
     if (!(rpm->op_pmflags & PMf_NONDESTRUCT)) {
 #ifndef PERL_ANY_COW
@@ -2930,7 +2932,7 @@ PP(pp_subst)
 
     orig = SvPV_nomg(TARG, len);
     /* note we don't (yet) force the var into being a string; if we fail
-     * to match, we leave as-is; on successful match howeverm, we *will*
+     * to match, we leave as-is; on successful match however, we *will*
      * coerce into a string, then repeat the match */
     if (!SvPOKp(TARG) || SvTYPE(TARG) == SVt_PVGV || SvVOK(TARG))
        force_on_match = 1;
@@ -3015,7 +3017,7 @@ PP(pp_subst)
     /* can do inplace substitution? */
     if (c
 #ifdef PERL_ANY_COW
-       && !is_cow
+       && !was_cow
 #endif
         && (I32)clen <= RX_MINLENRET(rx)
         && (  once
@@ -3028,6 +3030,7 @@ PP(pp_subst)
     {
 
 #ifdef PERL_ANY_COW
+        /* string might have got converted to COW since we set was_cow */
        if (SvIsCOW(TARG)) {
          if (!force_on_match)
            goto have_a_cow;
@@ -3623,6 +3626,8 @@ Perl_leave_adjust_stacks(pTHX_ SV **from_sp, SV **to_sp, U8 gimme, int pass)
 }
 
 
+/* also tail-called by pp_return */
+
 PP(pp_leavesub)
 {
     U8 gimme;