Fix a crash in "Subroutine redefined" warning

perl-5.25.2-SEGV-in-Subroutine-redefined-warning.patch

@@ -0,0 +1,76 @@
+From fc0fe26a7d286480c1bb25f57e469ece575bb68d Mon Sep 17 00:00:00 2001
+From: David Mitchell <davem@iabyn.com>
+Date: Thu, 7 Jul 2016 17:03:29 +0100
+Subject: [PATCH] SEGV in "Subroutine redefined" warning
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+RT #128257
+
+The following SEGVed:
+
+    sub P::f{}
+    undef *P::;
+    *P::f =sub{};
+
+due to the code which generates the "Subroutine STASH::NAME redefined"
+warning assuming that the GV always has a stash. Make it so that if it
+hasn't, the message changes to  "Subroutine NAME redefined" rather than
+just crashing.
+
+Signed-off-by: Petr Písař <ppisar@redhat.com>
+---
+ sv.c              | 18 +++++++++++-------
+ t/lib/warnings/sv |  8 ++++++++
+ 2 files changed, 19 insertions(+), 7 deletions(-)
+
+diff --git a/sv.c b/sv.c
+index 1b7a283..0cbe371 100644
+--- a/sv.c
++++ b/sv.c
+@@ -4074,14 +4074,18 @@ Perl_gv_setref(pTHX_ SV *const dstr, SV *const sstr)
+ 			    CvCONST((const CV *)sref)
+ 				 ? cv_const_sv((const CV *)sref)
+ 				 : NULL;
++                        HV * const stash = GvSTASH((const GV *)dstr);
+ 			report_redefined_cv(
+-			   sv_2mortal(Perl_newSVpvf(aTHX_
+-				"%"HEKf"::%"HEKf,
+-				HEKfARG(
+-				 HvNAME_HEK(GvSTASH((const GV *)dstr))
+-				),
+-				HEKfARG(GvENAME_HEK(MUTABLE_GV(dstr)))
+-			   )),
++			   sv_2mortal(
++                             stash
++                               ? Perl_newSVpvf(aTHX_
++				    "%"HEKf"::%"HEKf,
++				    HEKfARG(HvNAME_HEK(stash)),
++				    HEKfARG(GvENAME_HEK(MUTABLE_GV(dstr))))
++                               : Perl_newSVpvf(aTHX_
++				    "%"HEKf,
++				    HEKfARG(GvENAME_HEK(MUTABLE_GV(dstr))))
++			   ),
+ 			   cv,
+ 			   CvCONST((const CV *)sref) ? &new_const_sv : NULL
+ 			);
+diff --git a/t/lib/warnings/sv b/t/lib/warnings/sv
+index 5ddd4fe..c8e0e62 100644
+--- a/t/lib/warnings/sv
++++ b/t/lib/warnings/sv
+@@ -413,3 +413,11 @@ Argument "a_c" isn't numeric in preincrement (++) at - line 5.
+ Argument "(?^:abc)" isn't numeric in preincrement (++) at - line 6.
+ Argument "123x" isn't numeric in preincrement (++) at - line 7.
+ Argument "123e" isn't numeric in preincrement (++) at - line 8.
++########
++# RT #128257 This used to SEGV
++use warnings;
++sub Foo::f {}
++undef *Foo::;
++*Foo::f =sub {};
++EXPECT
++Subroutine f redefined at - line 5.
+-- 
+2.5.5
+

perl.spec

@@ -28,7 +28,7 @@
 Name:           perl
 Version:        %{perl_version}
 # release number must be even higher, because dual-lived modules will be broken otherwise
-Release:        372%{?dist}
+Release:        373%{?dist}
 Epoch:          %{perl_epoch}
 Summary:        Practical Extraction and Report Language
 Group:          Development/Languages
@@ -150,6 +150,10 @@ Patch39:        perl-5.25.2-Don-t-let-XSLoader-load-relative-paths.patch
 # in upstream after 5.25.2
 Patch40:        perl-5.25.2-perl-128532-Crash-vivifying-stub-in-deleted-pkg.patch
 
+# Fix a crash in "Subroutine redefined" warning, RT#128257,
+# in upstream after 5.25.2
+Patch41:        perl-5.25.2-SEGV-in-Subroutine-redefined-warning.patch
+
 # Link XS modules to libperl.so with EU::CBuilder on Linux, bug #960048
 Patch200:       perl-5.16.3-Link-XS-modules-to-libperl.so-with-EU-CBuilder-on-Li.patch
 
@@ -2809,6 +2813,7 @@ Perl extension for Version Objects
 %patch38 -p1
 %patch39 -p1
 %patch40 -p1
+%patch41 -p1
 %patch200 -p1
 %patch201 -p1
 
@@ -2840,6 +2845,7 @@ perl -x patchlevel.h \
     'Fedora Patch38: Fix line numbers with perl -x (RT#128508)' \
     'Fedora Patch39: Do not let XSLoader load relative paths (RT#115808)' \
     'Fedora Patch40: Fix a crash when vivifying a stub in a deleted package (RT#128532)' \
+    'Fedora Patch41: Fix a crash in "Subroutine redefined" warning (RT#128257)' \
     'Fedora Patch200: Link XS modules to libperl.so with EU::CBuilder on Linux' \
     'Fedora Patch201: Link XS modules to libperl.so with EU::MM on Linux' \
     %{nil}
@@ -5106,6 +5112,9 @@ popd
 
 # Old changelog entries are preserved in CVS.
 %changelog
+* Fri Jul 08 2016 Petr Pisar <ppisar@redhat.com> - 4:5.24.0-373
+- Fix a crash in "Subroutine redefined" warning (RT#128257)
+
 * Thu Jul 07 2016 Petr Pisar <ppisar@redhat.com> - 4:5.24.0-372
 - Fix a crash when vivifying a stub in a deleted package (RT#128532)