Merging media-libs/assimp-4.0.1 works on my system, but not without raising an eyebrow - i.e. a QA from gentoo: * QA Notice: Package triggers severe warnings which indicate that it * may exhibit random runtime failures. * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/AssbinExporter.cpp:642:60: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/AssbinExporter.cpp:643:60: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/AssbinExporter.cpp:644:60: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/BlenderScene.cpp:62:44: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/BlenderScene.cpp:103:46: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/BlenderScene.cpp:104:44: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/BlenderScene.cpp:108:44: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/BlenderScene.cpp:109:44: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/BlenderScene.cpp:110:44: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/BlenderScene.cpp:193:44: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/BlenderScene.cpp:207:44: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/BlenderScene.cpp:696:46: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/BlenderScene.cpp:697:44: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/BlenderScene.cpp:711:44: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/BlenderScene.cpp:712:44: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/FIReader.cpp:482:39: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/FIReader.cpp:500:40: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:234:71: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:264:88: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:317:71: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:234:71: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:264:88: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:317:71: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:234:71: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:264:88: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:317:71: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:234:71: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:264:88: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:317:71: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:234:71: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:264:88: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/contrib/Open3DGC/o3dgcBinaryStream.h:317:71: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/tools/assimp_cmd/WriteDumb.cpp:568:49: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/tools/assimp_cmd/WriteDumb.cpp:569:49: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/tools/assimp_cmd/WriteDumb.cpp:570:49: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/../contrib/Open3DGC/o3dgcBinaryStream.h:234:71: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/../contrib/Open3DGC/o3dgcBinaryStream.h:264:88: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/../contrib/Open3DGC/o3dgcBinaryStream.h:317:71: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/../contrib/Open3DGC/o3dgcBinaryStream.h:234:71: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/../contrib/Open3DGC/o3dgcBinaryStream.h:264:88: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * /zram/portage/media-libs/assimp-4.0.1/work/assimp-4.0.1/code/../contrib/Open3DGC/o3dgcBinaryStream.h:317:71: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] * Please do not file a Gentoo bug and instead report the above QA * issues directly to the upstream developers of this software. * Homepage: https://github.com/assimp/assimp The configuration that leads to these warnings is: -- <<< Gentoo configuration >>> Build type Gentoo Install path /usr Compiler flags: C -O2 -march=native -pipe -ftree-vectorize -fopenmp -fPIC C++ -O2 -march=native -pipe -ftree-vectorize -fopenmp -g -fvisibility=hidden -fPIC -Wall -std=c++0x Linker flags: Executable -Wl,-O1 -Wl,--as-needed Module -Wl,-O1 -Wl,--as-needed Shared -Wl,-O1 -Wl,--as-needed Some info --------- My flags from make.conf: CFLAGS="-O2 -march=native -pipe -ftree-vectorize" CXXFLAGS="${CFLAGS}" Top of 'emerge --info': Portage 2.3.51 (python 3.6.5-final-0, hardened/linux/amd64, gcc-7.3.0, glibc-2.27-r6, 4.19.18-gentoo x86_64) ================================================================= System uname: Linux-4.19.18-gentoo-x86_64-Intel-R-_Core-TM-_i7-6700HQ_CPU_@_2.60GHz-with-gentoo-2.6 KiB Mem: 40976252 total, 6665188 free KiB Swap: 25165820 total, 25165820 free Timestamp of repository gentoo: Thu, 13 Dec 2018 12:15:01 +0000 Head commit of repository gentoo: 057645ffcdb86bd24e7c965f6e1aa03db33abb4c sh bash 4.4_p12 ld GNU ld (Gentoo 2.30 p5) 2.30.0 app-shells/bash: 4.4_p12::gentoo dev-java/java-config: 2.2.0-r4::gentoo dev-lang/perl: 5.26.2::gentoo dev-lang/python: 2.7.15::gentoo, 3.4.8::gentoo, 3.5.5::gentoo, 3.6.5::gentoo dev-util/cmake: 3.12.3::gentoo dev-util/pkgconfig: 0.29.2::gentoo sys-apps/baselayout: 2.6-r1::gentoo sys-apps/openrc: 0.38.3-r1::gentoo sys-apps/sandbox: 2.13::gentoo sys-devel/autoconf: 2.13::gentoo, 2.69-r4::gentoo sys-devel/automake: 1.11.6-r3::gentoo, 1.12.6::gentoo, 1.13.4-r2::gentoo, 1.14.1::gentoo, 1.15.1-r2::gentoo sys-devel/binutils: 2.30-r4::gentoo sys-devel/gcc: 7.3.0-r3::gentoo sys-devel/gcc-config: 1.8-r1::gentoo sys-devel/libtool: 2.4.6-r3::gentoo sys-devel/make: 4.2.1-r4::gentoo sys-kernel/linux-headers: 4.19::gentoo (virtual/os-headers) sys-libs/glibc: 2.27-r6::gentoo Resolution ---------- It seems that the issue is known upstream: https://github.com/assimp/assimp/issues/2147 but it is marked as 'difficult', so it may take some time until it is resolved. Workaround ---------- To avoid the warnings, one should build assimp with the -fno-strict-aliasing C++ flag: As a user, create two files: 1. /etc/portage/env/no-strict-aliasing.conf with the content: CXXFLAGS="${CXXFLAGS} -fno-strict-aliasing" 2. /etc/portage/package.env/assimp with the content: media-libs/assimp no-strict-aliasing.conf With these two files in place (whose effect is to add '-fno-strict-aliasing"' to $CXXFLAGS of the user's make.conf file), assimp will be compiled without the above warnings - and with no QA notice. Suggestion ---------- My suggestion to the ebuild maintainer is to add '-fno-strict-aliasing"' to $CXXFLAGS in the ebuild, for as long as the issue has not been dealt with upstream - this will avoid embarrassing QA notices thrown at user's face and remove the need for extra env files in user portage.
Thanks for your report. I've updated an ebuild adding -fno-strict-aliasing argument. Newer assimp version seems to not have this warnings anymore, but I'm still testing ebuild for it, so now pushing just small fix for 4.0.1
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=ebd7fc118c9f57434fb1fe19bf6e70db3f86f13e commit ebd7fc118c9f57434fb1fe19bf6e70db3f86f13e Author: Slawomir Lis <slis@gentoo.org> AuthorDate: 2019-08-21 19:03:14 +0000 Commit: Slawomir Lis <slis@gentoo.org> CommitDate: 2019-08-21 19:03:35 +0000 media-libs/assimp: Strict aliasing error fix Closes: https://bugs.gentoo.org/677392 Package-Manager: Portage-2.3.71, Repoman-2.3.17 Signed-off-by: Slawek Lis <slis@gentoo.org> media-libs/assimp/assimp-4.0.1-r1.ebuild | 67 ++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+)
