From: Adrian M. Enache <enache@rdslink.ro>
Date: Sun, 3 Aug 2003 18:00:05 +0000 (+0300)
Subject: Re: [perl #23207] persistant sideffect involving bitwise xor and substr
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=6214ab63745c28e26e752f88d98bf89671cabc77;p=p5sagit%2Fp5-mst-13.2.git

Re: [perl #23207] persistant sideffect involving bitwise xor and substr
Message-ID: <20030803150005.GA1319@ratsnest.hole>

p4raw-id: //depot/perl@20462
---

diff --git a/pp.c b/pp.c
index 8a7632a..2958fba 100644
--- a/pp.c
+++ b/pp.c
@@ -3111,6 +3111,8 @@ PP(pp_substr)
 		sv_upgrade(TARG, SVt_PVLV);
 		sv_magic(TARG, Nullsv, PERL_MAGIC_substr, Nullch, 0);
 	    }
+	    else
+		(void)SvOK_off(TARG);
 
 	    LvTYPE(TARG) = 'x';
 	    if (LvTARG(TARG) != sv) {
diff --git a/t/op/substr.t b/t/op/substr.t
index 17f86e3..533f1a5 100755
--- a/t/op/substr.t
+++ b/t/op/substr.t
@@ -1,6 +1,6 @@
 #!./perl
 
-print "1..175\n";
+print "1..176\n";
 
 #P = start of string  Q = start of substr  R = end of substr  S = end of string
 
@@ -592,3 +592,13 @@ ok 174, $x eq "\x{100}\x{200}\xFFb";
     $r[$_] = \ substr $s, $_, 1 for (0, 1);
     ok 175, join("", map { $$_ } @r) eq "ab";
 }
+
+# [perl #23207]
+{
+    sub ss {
+	substr($_[0],0,1) ^= substr($_[0],1,1) ^=
+	substr($_[0],0,1) ^= substr($_[0],1,1);
+    }
+    my $x = my $y = 'AB'; ss $x; ss $y;
+    ok 176, $x eq $y;
+}