Bug 858515 – games-action/astromenace-1.4.1-r1 fails to compile (lto): menu_workshop_weaponry.cpp:51:17: error: WorkshopNewWeapon violates the C++ One Definition Rule [-Werror=odr]

• Status: RESOLVED FIXED
• Product: Gentoo Linux

[Description Agostino Sarubbo 2022-07-17 07:59:25 UTC]

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

Issue: games-action/astromenace-1.4.1-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 2022-07-17 07:59:27 UTC]

Created attachment 791855 [details]
build.log

build log and emerge --info

[Comment 2 Agostino Sarubbo 2022-07-17 07:59:29 UTC]

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


FAILED: astromenace 
/var/tmp/portage/games-action/astromenace-1.4.1-r1/work/astromenace-1.4.1/src/menu/menu_workshop_weaponry.cpp:51:17: error: ‘WorkshopNewWeapon’ violates the C++ One Definition Rule [-Werror=odr]

[Comment 3 Agostino Sarubbo 2022-07-26 09:01:36 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 Mikhail Kurinnoi 2023-04-28 17:47:28 UTC]

Hello,

I fixed this issue in upstream:
https://github.com/viewizard/astromenace/commit/710b35e786e5fe940a00b59c17eb638ec05a7a97

[Comment 5 Larry the Git Cow 2023-04-29 07:08:51 UTC]

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

https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=e956e4b31cb514f0ec71c993b5e84eba75a92ec0

commit e956e4b31cb514f0ec71c993b5e84eba75a92ec0
Author:     Sam James <[e-mail]>
AuthorDate: 2023-04-29 06:56:25 +0000
Commit:     Sam James <[e-mail]>
CommitDate: 2023-04-29 07:08:34 +0000

    games-action/astromenace: backport ODR fix
    
    Closes: https://bugs.gentoo.org/858515
    Signed-off-by: Sam James <[e-mail]>

 .../astromenace/astromenace-1.4.2-r1.ebuild        |  61 +++++++
 .../astromenace/files/astromenace-1.4.2-odr.patch  | 203 +++++++++++++++++++++
 2 files changed, 264 insertions(+)

[Comment 6 Sam James 2023-04-29 07:59:04 UTC]

(In reply to Mikhail Kurinnoi from comment #4)
> Hello,
> 
> I fixed this issue in upstream:
> https://github.com/viewizard/astromenace/commit/
> 710b35e786e5fe940a00b59c17eb638ec05a7a97

Thank you!