https://blogs.gentoo.org/ago/2020/07/04/gentoo-tinderbox/ Issue: games-util/grfcodec-6.0.6_p20210310 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 792377 [details] build.log build log and emerge --info
Error(s) that match a know pattern in addition to what has been reported in the summary: FAILED: grfcodec /var/tmp/portage/games-util/grfcodec-6.0.6_p20210310/work/grfcodec-045774dee7cab1a618a3e0d9b39bff78a12b6efa/src/escapes.h:98:1: error: type ‘struct esc’ 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 referenced in the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=810cbfa3961719466326528a442a8d114e1f6fd6 commit 810cbfa3961719466326528a442a8d114e1f6fd6 Author: David Seifert <soap@gentoo.org> AuthorDate: 2022-10-08 14:58:38 +0000 Commit: David Seifert <soap@gentoo.org> CommitDate: 2022-10-08 14:58:38 +0000 games-util/grfcodec: update EAPI 7 -> 8 Bug: https://bugs.gentoo.org/715910 Bug: https://bugs.gentoo.org/859310 Signed-off-by: David Seifert <soap@gentoo.org> .../0001-Remove-brittle-apWrapper-code.patch | 144 +++++++++++++++++++++ .../6.0.6_p20210310/0002-Fix-ODR-violations.patch | 63 +++++++++ .../grfcodec/grfcodec-6.0.6_p20210310-r1.ebuild | 40 ++++++ 3 files changed, 247 insertions(+)
Untested but believe this was meant to be closed by comment #4 which includes a patch about this.