Accepting request 809200 from home:marxin:branches:X11:XOrg

- Add add-lifetime-dse-fix.patch as a proper fix for boo#1171855.

OBS-URL: https://build.opensuse.org/request/show/809200
OBS-URL: https://build.opensuse.org/package/show/X11:XOrg/Mesa?expand=0&rev=958

Mesa-drivers.changes

@@ -1,3 +1,8 @@
+-------------------------------------------------------------------
+Tue May 19 19:22:02 UTC 2020 - Martin Liška <mliska@suse.cz>
+
+- Add add-lifetime-dse-fix.patch as a proper fix for boo#1171855.
+
 -------------------------------------------------------------------
 Tue May 19 05:52:31 UTC 2020 - Martin Liška <mliska@suse.cz>
 

Mesa-drivers.spec

@@ -32,8 +32,9 @@
 # Note that if you actually need to render something, you need the packages
 # from Mesa-driver.
 
-# Disable LTO for now boo#1171855
+%ifarch armv6l armv6hl
 %define _lto_cflags %{nil}
+%endif
 
 ##### WARNING: please do not edit this auto generated spec file. Use the Mesa.spec! #####
 %define drivers 1
@@ -128,6 +129,7 @@ Source4:        manual-pages.tar.bz2
 Source6:        %{name}-rpmlintrc
 Source7:        Mesa.keyring
 Patch2:         n_add-Mesa-headers-again.patch
+Patch3:         add-lifetime-dse-fix.patch
 # never to be upstreamed
 Patch54:        n_drirc-disable-rgb10-for-chromium-on-amd.patch
 Patch58:        u_dep_xcb.patch
@@ -735,6 +737,7 @@ programs against the XA state tracker.
 rm -rf docs/README.{VMS,WIN32,OS2}
 
 %patch2 -p1
+%patch3 -p1
 %patch54 -p1
 %patch58 -p1
 

add-lifetime-dse-fix.patch

@@ -0,0 +1,46 @@
+From 9a72afaea7bf69f07623cae1af99f71be64688ba Mon Sep 17 00:00:00 2001
+From: Danylo Piliaiev <danylo.piliaiev@globallogic.com>
+Date: Tue, 19 May 2020 20:35:49 +0300
+Subject: [PATCH] meson: Disable GCC's dead store elimination for memory
+ zeroing custom new
+
+Some classes use custom new operator which zeroes memory, however gcc does
+aggressive dead-store elimination which threats all writes to the memory
+before the constructor as "dead stores".
+
+For now we disable this optimization.
+
+The new operators in question are declared via:
+ DECLARE_RZALLOC_CXX_OPERATORS
+ DECLARE_LINEAR_ZALLOC_CXX_OPERATORS
+
+The issue was found with lto builds, however there is no guarantee that
+it didn't happen with ordinary ones.
+
+CC: <mesa-stable@lists.freedesktop.org>
+Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/2977
+Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/1358
+Signed-off-by: Danylo Piliaiev <danylo.piliaiev@globallogic.com>
+---
+ meson.build | 5 +++++
+ 1 file changed, 5 insertions(+)
+
+diff --git a/meson.build b/meson.build
+index 1a207842c55..3d4ea165c99 100644
+--- a/meson.build
++++ b/meson.build
+@@ -980,6 +980,11 @@ else
+     '-fno-math-errno',
+     '-fno-trapping-math',
+     '-Qunused-arguments',
++    # Some classes use custom new operator which zeroes memory, however
++    # gcc does aggressive dead-store elimination which threats all writes
++    # to the memory before the constructor as "dead stores".
++    # For now we disable this optimization.
++    '-flifetime-dse=1',
+   ]
+   # MinGW chokes on format specifiers and I can't get it all working
+   if not (cc.get_id() == 'gcc' and host_machine.system() == 'windows')
+-- 
+2.26.2
+