Bug 865281 – app-admin/calamares-3.2.60 does not respect LDFLAGS

• Product: Gentoo Linux
• Status: RESOLVED FIXED

[Description Agostino Sarubbo 2022-08-15 18:27:05 UTC]

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

Issue: app-admin/calamares-3.2.60 does not respect LDFLAGS.
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
To reproduce this issue you may want to set LDFLAGS="${LDFLAGS} -Wl,--defsym=__gentoo_check_ldflags__=0". If this is not something about c/c++ context you may want to see this bug as an hint to hide the QA warning (with QA_FLAGS_IGNORED) where is not possible to respect LDFLAGS.

[Comment 1 Agostino Sarubbo 2022-08-15 18:27:07 UTC]

Created attachment 799779 [details]
build.log.xz

build log and emerge --info (compressed because it exceeds attachment limit, use 'xzless' to read it)

[Comment 2 Larry the Git Cow 2023-03-18 20:09:22 UTC]

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

https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=c497ddda658af5747f1c3a1f72df7b80cec047bd

commit c497ddda658af5747f1c3a1f72df7b80cec047bd
Author:     Mario Haustein <[e-mail]>
AuthorDate: 2023-03-18 19:58:08 +0000
Commit:     Ulrich Müller <[e-mail]>
CommitDate: 2023-03-18 20:03:13 +0000

    app-admin/calamares: respect LDFLAGS
    
    Closes: https://bugs.gentoo.org/865281
    Signed-off-by: Mario Haustein <[e-mail]>
    Signed-off-by: Ulrich Müller <[e-mail]>

 ...{calamares-3.2.60.ebuild => calamares-3.2.60-r1.ebuild} |  4 ++++
 app-admin/calamares/files/calamares-3.2.60-ldflags.patch   | 14 ++++++++++++++
 2 files changed, 18 insertions(+)