https://blogs.gentoo.org/ago/2020/07/04/gentoo-tinderbox/ Issue: x11-plugins/wmcalendar-0.5.2-r2 fails to compile (LTO-SYSTEM). Discovered on: amd64 (internal ref: lto_tinderbox) NOTE: (LTO-SYSTEM) in the summary means that bug was found on a machine that runs lto but this bug MAY or MAY NOT BE related to lto. This machine uses lto with CFLAGS=-flto -Werror=odr -Werror=lto-type-mismatch -Werror=strict-aliasing 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
Created attachment 832881 [details] build.log build log and emerge --info
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=054d5d2c0cfd27716cf924e7f5b335a43dcf1217 commit 054d5d2c0cfd27716cf924e7f5b335a43dcf1217 Author: Eli Schwartz <eschwartz93@gmail.com> AuthorDate: 2024-04-28 05:42:46 +0000 Commit: Sam James <sam@gentoo.org> CommitDate: 2024-04-28 06:54:26 +0000 x11-plugins/wmcalendar: add patches to fix horrible missing function decls We kill two birds with one stone. It fails the c99 porting tracker and will not compile with Modern C compilers such as gcc 14 or clang 16, and it ALSO fixes LTO errors since -Werror=lto-type-mismatch complained when the implicit function declaration's assumed type was incorrect and didn't match the type of the actual live instance of the function. While we are at it, fix some additional (memory access) errors discovered by LTO in the form of -Waggressive-loop-optimizations. Closes: https://bugs.gentoo.org/875530 Closes: https://bugs.gentoo.org/881461 Signed-off-by: Eli Schwartz <eschwartz93@gmail.com> Signed-off-by: Sam James <sam@gentoo.org> ...-typo-causing-out-of-bounds-memory-access.patch | 27 ++++++++++ x11-plugins/wmcalendar/files/wmcalendar-c99.patch | 63 ++++++++++++++++++++++ x11-plugins/wmcalendar/wmcalendar-0.5.2-r3.ebuild | 39 ++++++++++++++ 3 files changed, 129 insertions(+)
