Bug 862714 – sci-libs/h5hut-1.99.13-r1 fails to compile (lto): h5_fcmp.c:25:28: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing]

• Product: Gentoo Linux
• Status: RESOLVED PKGREMOVED

[Description Agostino Sarubbo 2022-08-01 07:58:39 UTC]

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

Issue: sci-libs/h5hut-1.99.13-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

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 1 Agostino Sarubbo 2022-08-01 07:58:42 UTC]

Created attachment 796456 [details]
build.log

build log and emerge --info

[Comment 2 Larry the Git Cow 2024-07-26 15:17:09 UTC]

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

https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=c7d8b5cfc238fb087eca8b22ca04e1b70aa93c5a

commit c7d8b5cfc238fb087eca8b22ca04e1b70aa93c5a
Author:     Arthur Zamarin <[e-mail]>
AuthorDate: 2024-07-26 15:11:12 +0000
Commit:     Arthur Zamarin <[e-mail]>
CommitDate: 2024-07-26 15:16:22 +0000

    sci-libs/h5hut: treeclean
    
    Closes: https://bugs.gentoo.org/934689 (pkgremoved)
    Closes: https://bugs.gentoo.org/862714 (pkgremoved)
    Closes: https://bugs.gentoo.org/849920 (pkgremoved)
    Closes: https://bugs.gentoo.org/832789 (pkgremoved)
    Closes: https://bugs.gentoo.org/828579 (pkgremoved)
    Closes: https://bugs.gentoo.org/741440 (pkgremoved)
    Signed-off-by: Arthur Zamarin <[e-mail]>

 profiles/package.mask                              |  6 --
 sci-libs/h5hut/Manifest                            |  1 -
 sci-libs/h5hut/files/h5hut-1.99.13-autotools.patch | 77 ----------------------
 sci-libs/h5hut/files/h5hut-1.99.13-mpio.patch      | 12 ----
 sci-libs/h5hut/h5hut-1.99.13-r1.ebuild             | 40 -----------
 sci-libs/h5hut/metadata.xml                        |  8 ---
 6 files changed, 144 deletions(-)