https://blogs.gentoo.org/ago/2020/07/04/gentoo-tinderbox/ Issue: media-libs/coin-4.0.0 fails to compile (lto). Discovered on: amd64 (internal ref: lto_tinderbox) NOTE: This machine uses lto with CFLAGS=-flto -Werror=odr -Werror=lto-type-mismatch -Werror=strict-aliasing
Created attachment 792923 [details] build.log.xz build log and emerge --info (compressed because it exceeds attachment limit, use 'xzless' to read it)
Error(s) that match a know pattern in addition to what has been reported in the summary: FAILED: lib/libCoin.so.4.0.0 /var/tmp/portage/media-libs/coin-4.0.0/work/coin/src/scxml/eval-minimum-tab.hpp:58:15: error: type ‘union YYSTYPE’ violates the C++ One Definition Rule [-Werror=odr]
Here is a bit of explanation: -Werror=lto-type-mismatch: User to find possible runtime issues in packages. It likely means the package is unsafe to build & use with LTO. For projects using the same identifier but with different types across different files, they must be fixed to be consistent across the codebase. -Werror=odr: Used to find possible runtime issues in packages. These bugs are a problem anyway but may be even worse when combined with LTO. C++ code must comply with the One Definition Rule (ODR) - see https://en.cppreference.com/w/cpp/language/definition#One_Definition_Rule. -Werror=strict-aliasing: Used to find possible runtime issues in packages. These bugs are a problem anyway but may be even worse when combined with LTO. Workarounds: - If upstream is friendly and still active, file a bug upstream. For emulators, codecs, games, or multimedia packages, it may be worth just applying a workaround instead, as upstreams sometimes aren't receptive to these bugs (VALID FOR ALL). - Use the new 'filter-lto' from flag-o-matic.eclass as it's likely to be unsafe with LTO (VALID FOR lto-type-mismatch - odr). - Fix it yourself if interested, of course (VALID FOR ALL). - Append-flags -fno-strict-aliasing (VALID FOR strict-aliasing). - Use memcpy() but a union is sometimes suitable too (VALID FOR strict-aliasing). - -fstrict-aliasing is implied by -O2, so this must be addressed in some form (VALID FOR strict-aliasing). See also: https://marc.info/?l=gentoo-dev&m=165639574126280&w=2
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=5a63a911321a866495c7c3c893389c0430599e82 commit 5a63a911321a866495c7c3c893389c0430599e82 Author: Eli Schwartz <eschwartz93@gmail.com> AuthorDate: 2024-03-05 05:01:03 +0000 Commit: Sam James <sam@gentoo.org> CommitDate: 2024-03-05 05:08:29 +0000 media-libs/coin: mark as LTO-unsafe Closes: https://bugs.gentoo.org/859832 Signed-off-by: Eli Schwartz <eschwartz93@gmail.com> Signed-off-by: Sam James <sam@gentoo.org> media-libs/coin/coin-4.0.0.ebuild | 5 +++++ media-libs/coin/coin-4.0.1.ebuild | 5 +++++ media-libs/coin/coin-4.0.2.ebuild | 5 +++++ 3 files changed, 15 insertions(+)