From: Bo Borgerson <gigabo@gmail.com>
Date: Mon, 2 Nov 2009 17:25:23 +0000 (-0600)
Subject: [PATCH] [perl #20321] Non-destructive Perl_av_make
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=2b6765935f5ee68d8093e686b8e292ad5de5a898;p=p5sagit%2Fp5-mst-13.2.git

[PATCH] [perl #20321] Non-destructive Perl_av_make

Don't let sv_setsv swipe temps in av_make, since the source array
might have multiple references to the same temp scalar (e.g. from
a list slice).
---

diff --git a/av.c b/av.c
index 4718af2..a4d6ea2 100644
--- a/av.c
+++ b/av.c
@@ -404,8 +404,14 @@ Perl_av_make(pTHX_ register I32 size, register SV **strp)
 	AvFILLp(av) = AvMAX(av) = size - 1;
 	for (i = 0; i < size; i++) {
 	    assert (*strp);
+
+	    /* Don't let sv_setsv swipe, since our source array might
+	       have multiple references to the same temp scalar (e.g.
+	       from a list slice) */
+
 	    ary[i] = newSV(0);
-	    sv_setsv(ary[i], *strp);
+	    sv_setsv_flags(ary[i], *strp,
+			   SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
 	    strp++;
 	}
     }
diff --git a/t/op/list.t b/t/op/list.t
index a8fdc18..184724a 100644
--- a/t/op/list.t
+++ b/t/op/list.t
@@ -6,7 +6,7 @@ BEGIN {
 }
 
 require "test.pl";
-plan( tests => 57 );
+plan( tests => 58 );
 
 @foo = (1, 2, 3, 4);
 cmp_ok($foo[0], '==', 1, 'first elem');
@@ -161,3 +161,7 @@ cmp_ok(join('',(1,2),3,(4,5)),'eq','12345','list (..).(..)');
     test_zero_args("do-returned list slice", do { (10,11)[2,3]; });
 }
 
+{
+    # perl #20321
+    is (join('', @{[('abc'=~/./g)[0,1,2,1,0]]}), "abcba");
+}