Bug 860183 – [guru] media-video/uxplay-1.54 fails to compile (lto): video_renderer.h:53:6: error: type of video_renderer_flush does not match original declaration [-Werror=lto-type-mismatch]

• Status: RESOLVED FIXED
• Product: GURU

[Description Agostino Sarubbo 2022-07-23 06:41:22 UTC]

https://blogs.gentoo.org/ago/2020/07/04/gentoo-tinderbox/

Issue: media-video/uxplay-1.54 fails to compile (lto).
Discovered on: amd64 (internal ref: guru_tinderbox)

NOTE:
This machine uses lto with CFLAGS=-flto -Werror=odr -Werror=lto-type-mismatch -Werror=strict-aliasing

[Comment 1 Agostino Sarubbo 2022-07-23 06:41:24 UTC]

Created attachment 793280 [details]
build.log

build log and emerge --info

[Comment 2 Agostino Sarubbo 2022-07-23 06:41:25 UTC]

Error(s) that match a know pattern in addition to what has been reported in the summary:


FAILED: uxplay 
/var/tmp/portage/media-video/uxplay-1.54/work/UxPlay-1.54/renderers/video_renderer.h:53:6: error: type of ‘video_renderer_flush’ does not match original declaration [-Werror=lto-type-mismatch]

[Comment 3 Petrus Zhao 2022-07-23 13:21:01 UTC]

I reported it to the upstream. Thank you.

[Comment 4 Agostino Sarubbo 2022-07-26 09:08:56 UTC]

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

[Comment 5 Larry the Git Cow 2022-08-02 10:55:10 UTC]

The bug has been closed via the following commit(s):

https://gitweb.gentoo.org/repo/proj/guru.git/commit/?id=cdd4289e48d30a9b2574651e6a710ba451b45a77

commit cdd4289e48d30a9b2574651e6a710ba451b45a77
Author:     Petrus Zhao <[e-mail]>
AuthorDate: 2022-07-24 14:28:04 +0000
Commit:     Petrus Zhao <[e-mail]>
CommitDate: 2022-07-24 14:28:04 +0000

    media-video/uxplay: version bump to 1.55, drop old
    
    Closes: https://bugs.gentoo.org/860183
    Package-Manager: Portage-3.0.30, Repoman-3.0.3
    Signed-off-by: Petrus Zhao <[e-mail]>

 media-video/uxplay/Manifest                                   | 2 +-
 media-video/uxplay/{uxplay-1.54.ebuild => uxplay-1.55.ebuild} | 0
 2 files changed, 1 insertion(+), 1 deletion(-)