From d8084ca508cc868d52c8d8d4fcfc637d4dbec9d0 Mon Sep 17 00:00:00 2001
From: Dave Mitchell <davem@fdisolutions.com>
Date: Thu, 30 Jun 2005 22:41:07 +0000
Subject: [PATCH] [perl #36434] assigning shared consts (eg __PACKAGE__) to
 magic vars

p4raw-id: //depot/perl@25032
---
 sv.c         | 7 ++++++-
 t/op/magic.t | 9 ++++++---
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/sv.c b/sv.c
index 101f8b631b..35af580364 100644
--- a/sv.c
+++ b/sv.c
@@ -4984,7 +4984,12 @@ Perl_sv_magic(pTHX_ register SV *sv, SV *obj, int how, const char *name, I32 nam
         sv_force_normal_flags(sv, 0);
 #endif
     if (SvREADONLY(sv)) {
-	if (IN_PERL_RUNTIME
+	if (
+	    /* its okay to attach magic to shared strings; the subsequent
+	     * upgrade to PVMG will unshare the string */
+	    !(SvFAKE(sv) && SvTYPE(sv) < SVt_PVMG)
+
+	    && IN_PERL_RUNTIME
 	    && how != PERL_MAGIC_regex_global
 	    && how != PERL_MAGIC_bm
 	    && how != PERL_MAGIC_fm
diff --git a/t/op/magic.t b/t/op/magic.t
index 154a3cccd4..c8a2224703 100755
--- a/t/op/magic.t
+++ b/t/op/magic.t
@@ -36,7 +36,7 @@ sub skip {
     return 1;
 }
 
-print "1..56\n";
+print "1..57\n";
 
 $Is_MSWin32  = $^O eq 'MSWin32';
 $Is_NetWare  = $^O eq 'NetWare';
@@ -432,9 +432,12 @@ ok "@+" eq "10 1 6 10";
     local @ISA;
     local %ENV;
     eval { push @ISA, __PACKAGE__ };
-    ok( $@ eq '', 'Push a constant on a magic array', '#36434' );
+    ok( $@ eq '', 'Push a constant on a magic array');
     $@ and print "# $@";
     eval { %ENV = (PATH => __PACKAGE__) };
-    ok( $@ eq '', 'Assign a constant to a magic hash', '#36434' );
+    ok( $@ eq '', 'Assign a constant to a magic hash');
+    $@ and print "# $@";
+    eval { my %h = qw(A B); %ENV = (PATH => (keys %h)[0]) };
+    ok( $@ eq '', 'Assign a shared key to a magic hash');
     $@ and print "# $@";
 }