Bug 859925 – media-libs/libvmaf-2.3.0-r2 fails to compile (lto): model.c:40:19: error: type of src_vmaf_4k_v0_6_1_json does not match original declaration [-Werror=lto-type-mismatch]

• Status: RESOLVED FIXED
• Product: Gentoo Linux

[Description Agostino Sarubbo 2022-07-22 06:50:19 UTC]

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

Issue: media-libs/libvmaf-2.3.0-r2 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

[Comment 1 Agostino Sarubbo 2022-07-22 06:50:21 UTC]

Created attachment 793013 [details]
build.log

build log and emerge --info

[Comment 2 Agostino Sarubbo 2022-07-22 06:50:23 UTC]

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


FAILED: src/libvmaf.so.1.1.2 
FAILED: tools/vmaf 
FAILED: tools/vmafossexec 
Program doxygen found: NO
fatal: not a git repository: '/var/tmp/portage/media-libs/libvmaf-2.3.0-r2/work/vmaf-2.3.0/libvmaf/../.git'
../vmaf-2.3.0/libvmaf/src/model.c:40:19: error: type of ‘src_vmaf_4k_v0_6_1_json’ does not match original declaration [-Werror=lto-type-mismatch]

[Comment 3 Agostino Sarubbo 2022-07-26 09:02:31 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 4 Larry the Git Cow 2023-10-06 12:46:52 UTC]

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

https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=a819064cbb3eab9678311c2b992b3db9eefb3a5d

commit a819064cbb3eab9678311c2b992b3db9eefb3a5d
Author:     Adel KARA SLIMANE <[e-mail]>
AuthorDate: 2023-08-19 23:19:24 +0000
Commit:     Joonas Niilola <[e-mail]>
CommitDate: 2023-10-06 12:46:49 +0000

    media-libs/libvmaf: add 2.3.1, drop 2.3.0-r2
    
    Closes: https://bugs.gentoo.org/859925
    Signed-off-by: Adel KARA SLIMANE <[e-mail]>
    Signed-off-by: Joonas Niilola <[e-mail]>

 media-libs/libvmaf/Manifest                                          | 2 +-
 media-libs/libvmaf/{libvmaf-2.3.0-r2.ebuild => libvmaf-2.3.1.ebuild} | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)