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Bug 859973 - [guru] games-emulation/dosbox-x-0.84.1 fails to compile (lto): physfs_lzmasdk.h:933:16: error: type [-Werror=odr]
Summary: [guru] games-emulation/dosbox-x-0.84.1 fails to compile (lto): physfs_lzmasdk...
Alias: None
Product: GURU
Classification: Unclassified
Component: Package issues (show other bugs)
Hardware: All Linux
: Normal normal
Assignee: Yuan Liao (Leo3418)
Depends on:
Reported: 2022-07-22 07:29 UTC by Agostino Sarubbo
Modified: 2022-12-27 08:05 UTC (History)
1 user (show)

See Also:
Package list:
Runtime testing required: ---

build.log.xz (build.log.xz,34.78 KB, application/x-xz)
2022-07-22 07:29 UTC, Agostino Sarubbo

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Description Agostino Sarubbo gentoo-dev 2022-07-22 07:29:13 UTC

Issue: games-emulation/dosbox-x-0.84.1 fails to compile (lto).
Discovered on: amd64 (internal ref: guru_tinderbox)

This machine uses lto with CFLAGS=-flto -Werror=odr -Werror=lto-type-mismatch -Werror=strict-aliasing
Comment 1 Agostino Sarubbo gentoo-dev 2022-07-22 07:29:16 UTC
Created attachment 793061 [details]

build log and emerge --info (compressed because it exceeds attachment limit, use 'xzless' to read it)
Comment 2 Agostino Sarubbo gentoo-dev 2022-07-26 09:08:47 UTC
Here is a bit of explanation:

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.

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

Used to find possible runtime issues in packages. These bugs are a problem anyway but may be even worse when combined with LTO.

- 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:
Comment 3 Larry the Git Cow gentoo-dev 2022-08-24 15:52:04 UTC
The bug has been closed via the following commit(s):

commit d1ff3cc3ee1e50e94bf9b49660c515d27a3a15de
Author:     Yuan Liao <>
AuthorDate: 2022-08-23 19:57:43 +0000
Commit:     Yuan Liao <>
CommitDate: 2022-08-23 19:58:19 +0000

    games-emulation/dosbox-x: Filter LTO flags
    Signed-off-by: Yuan Liao <>

 games-emulation/dosbox-x/dosbox-x-0.84.1.ebuild    | 7 ++++++-
 games-emulation/dosbox-x/dosbox-x-2022.08.0.ebuild | 7 ++++++-
 games-emulation/dosbox-x/dosbox-x-9999.ebuild      | 7 ++++++-
 3 files changed, 18 insertions(+), 3 deletions(-)
Comment 4 Larry the Git Cow gentoo-dev 2022-09-08 01:46:39 UTC
The bug has been referenced in the following commit(s):

commit dcc517c60cca527a2d32569575032e00875fac1f
Author:     Yuan Liao <>
AuthorDate: 2022-09-07 14:49:13 +0000
Commit:     Yuan Liao <>
CommitDate: 2022-09-07 14:49:13 +0000

    games-emulation/dosbox-x: Unfilter LTO flags for latest Git revisions
    The upstream has fixed the LTO build failure.
    Signed-off-by: Yuan Liao <>

 games-emulation/dosbox-x/dosbox-x-9999.ebuild | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)
Comment 5 Larry the Git Cow gentoo-dev 2022-12-27 08:05:50 UTC
The bug has been referenced in the following commit(s):

commit e52a88b468775df39735b75167f2ae78cf268b8b
Author:     Yuan Liao <>
AuthorDate: 2022-12-22 00:33:21 +0000
Commit:     Yuan Liao <>
CommitDate: 2022-12-22 00:40:21 +0000

    games-emulation/dosbox-x: Backport upstream LTO ODR fix to 2022.08.0
    Not bumping revision for this change because the ebuild for 2022.08.0
    has just been revision-bumped in the previous commit.
    Signed-off-by: Yuan Liao <>

 .../dosbox-x/dosbox-x-2022.08.0-r1.ebuild          |  14 +-
 .../files/dosbox-x-2022.08.0-fix-lto-odr.patch     | 368 +++++++++++++++++++++
 2 files changed, 376 insertions(+), 6 deletions(-)