Bug 854546 – app-forensics/libewf-20171104-r2 fails to compile (lto): libodraw_cue_parser.c:417:12: error: type of cue_scanner_lex does not match original declaration [-Werror=lto-type-mismatch]

• Status: RESOLVED PKGREMOVED
• Product: Gentoo Linux

[Description Agostino Sarubbo 2022-06-27 06:20:23 UTC]

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

Issue: app-forensics/libewf-20171104-r1 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 2022-06-27 06:20:25 UTC]

Created attachment 787904 [details]
build.log

build log and emerge --info

[Comment 2 Agostino Sarubbo 2022-07-26 09:00:19 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 3 Agostino Sarubbo 2024-02-13 08:10:19 UTC]

lto_tinderbox has reproduced this issue with version 20171104-r2 - Updating summary.

[Comment 4 Larry the Git Cow 2024-05-31 19:18:35 UTC]

The bug has been referenced in the following commit(s):

https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=2ef3b135c8bf4713763db3e357c5c29f4667ff4d

commit 2ef3b135c8bf4713763db3e357c5c29f4667ff4d
Author:     Arthur Zamarin <[e-mail]>
AuthorDate: 2024-05-31 19:16:54 +0000
Commit:     Arthur Zamarin <[e-mail]>
CommitDate: 2024-05-31 19:16:54 +0000

    app-forensics/libewf: treeclean
    
    Closes: https://bugs.gentoo.org/927076
    Bug: https://bugs.gentoo.org/854546
    Signed-off-by: Arthur Zamarin <[e-mail]>

 app-forensics/libewf/Manifest                      |  1 -
 .../libewf/files/libewf-20171104-openssl-3.patch   | 27 ---------
 app-forensics/libewf/libewf-20171104-r2.ebuild     | 66 ----------------------
 app-forensics/libewf/metadata.xml                  | 13 -----
 profiles/package.mask                              |  7 ---
 5 files changed, 114 deletions(-)