Fix an arithmetic left shift of a minimal integer value

perl-5.33.8-Fix-broken-left-shift-of-IV_MIN-under-use-integer.patch

@@ -0,0 +1,62 @@
+From 4e82c85b1c9c9b30253b8624470da6f20a6c0604 Mon Sep 17 00:00:00 2001
+From: Karl Williamson <khw@cpan.org>
+Date: Mon, 15 Mar 2021 21:01:47 -0600
+Subject: [PATCH] Fix broken left shift of IV_MIN under 'use integer'
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+This fixes GH 18639
+
+When I wrote this code, I conflated casting and complementing.
+
+Signed-off-by: Petr Písař <ppisar@redhat.com>
+---
+ pp.c       | 3 ---
+ t/op/bop.t | 9 ++++++++-
+ 2 files changed, 8 insertions(+), 4 deletions(-)
+
+diff --git a/pp.c b/pp.c
+index d365afea4c..baf0777a47 100644
+--- a/pp.c
++++ b/pp.c
+@@ -2007,9 +2007,6 @@ static IV S_iv_shift(IV iv, int shift, bool left)
+      * 18446744073709551552
+      * */
+     if (left) {
+-        if (iv == IV_MIN) { /* Casting this to a UV is undefined behavior */
+-            return 0;
+-        }
+         return (IV) (((UV) iv) << shift);
+     }
+ 
+diff --git a/t/op/bop.t b/t/op/bop.t
+index 07f057d0a9..31b6531a03 100644
+--- a/t/op/bop.t
++++ b/t/op/bop.t
+@@ -18,7 +18,7 @@ BEGIN {
+ # If you find tests are failing, please try adding names to tests to track
+ # down where the failure is, and supply your new names as a patch.
+ # (Just-in-time test naming)
+-plan tests => 502;
++plan tests => 503;
+ 
+ # numerics
+ ok ((0xdead & 0xbeef) == 0x9ead);
+@@ -33,6 +33,13 @@ ok ((33023 >> 7) == 257);
+ # signed vs. unsigned
+ ok ((~0 > 0 && do { use integer; ~0 } == -1));
+ 
++{   # GH #18639
++    my $iv_min = -(~0 >> 1) - 1;
++    my $shifted;
++    { use integer; $shifted = $iv_min << 0 };
++    is($shifted, $iv_min, "IV_MIN << 0 yields IV_MIN under 'use integer'");
++}
++
+ my $bits = 0;
+ for (my $i = ~0; $i; $i >>= 1) { ++$bits; }
+ my $cusp = 1 << ($bits - 1);
+-- 
+2.26.3
+

perl.spec

@@ -276,6 +276,10 @@ Patch56:        perl-5.33.7-regcomp.c-Remove-memory-leak.patch
 # Fix dumping a hash entry of PL_strtab type, in upstream after 5.33.7
 Patch57:        perl-5.32.1-Perl_do_sv_dump-handle-PL_strtab.patch
 
+# Fix an arithmetic left shift of a minimal integer value, GH#18639,
+# in upstream after 5.33.8
+Patch58:        perl-5.33.8-Fix-broken-left-shift-of-IV_MIN-under-use-integer.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
 
@@ -4334,6 +4338,7 @@ you're not running VMS, this module does nothing.
 %patch55 -p1
 %patch56 -p1
 %patch57 -p1
+%patch58 -p1
 %patch200 -p1
 %patch201 -p1
 
@@ -4390,6 +4395,7 @@ perl -x patchlevel.h \
     'Fedora Patch55: Prevent the number of buckets in a hash from getting too large' \
     'Fedora Patch56: Fix a memory leak when compiling a regular expression (GH#18604)' \
     'Fedora Patch57: Fix dumping a hash entry of PL_strtab type' \
+    'Fedora Patch57: Fix an arithmetic left shift of a minimal integer value (GH#18639)' \
     '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}
@@ -7166,6 +7172,7 @@ popd
 %changelog
 * Wed Mar 31 2021 Petr Pisar <ppisar@redhat.com> - 4:5.32.1-474
 - Fix dumping a hash entry of PL_strtab type
+- Fix an arithmetic left shift of a minimal integer value (GH#18639)
 
 * Thu Mar 04 2021 Jitka Plesnikova <jplesnik@redhat.com> - 4:5.32.1-473
 - Remove files excluded from dual-lived subpackages