Summary: | media-libs/exempi-2.4.5-r1 fails to compile (lto): EndianUtils.hpp:207:18: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing] | ||
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Product: | Gentoo Linux | Reporter: | Agostino Sarubbo <ago> |
Component: | Current packages | Assignee: | Freedesktop bugs <freedesktop-bugs> |
Status: | RESOLVED FIXED | ||
Severity: | normal | ||
Priority: | Normal | ||
Version: | unspecified | ||
Hardware: | All | ||
OS: | Linux | ||
See Also: | https://bugs.gentoo.org/show_bug.cgi?id=653240 | ||
Whiteboard: | |||
Package list: | Runtime testing required: | --- | |
Bug Depends on: | |||
Bug Blocks: | 618550 | ||
Attachments: | build.log |
Description
Agostino Sarubbo
2022-07-21 20:03:16 UTC
Created attachment 792932 [details]
build.log
build log and emerge --info
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=8d5482040ac6faa59317a0d51503cd9d0991aed0 commit 8d5482040ac6faa59317a0d51503cd9d0991aed0 Author: Sam James <sam@gentoo.org> AuthorDate: 2022-10-29 20:03:03 +0000 Commit: Sam James <sam@gentoo.org> CommitDate: 2022-10-29 20:03:37 +0000 media-libs/exempi: add 2.6.2 Bug: https://bugs.gentoo.org/653240 Bug: https://bugs.gentoo.org/764536 Bug: https://bugs.gentoo.org/859841 Signed-off-by: Sam James <sam@gentoo.org> media-libs/exempi/Manifest | 1 + media-libs/exempi/exempi-2.6.2.ebuild | 65 +++++++++++++++++++++++++++++++++++ 2 files changed, 66 insertions(+) |