https://blogs.gentoo.org/ago/2020/07/04/gentoo-tinderbox/ Issue: net-dns/maradns-3.5.0020 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
Created attachment 794654 [details] build.log build log and emerge --info
lto_tinderbox has reproduced this issue with version 3.5.0022 - Updating summary.
Dear portage team, may I ask why this ebuild fails in src_compile but does not die there and instead dies in src_install? I can reproduce with the latest, but at that point there was the ebuild: https://github.com/gentoo-mirror/gentoo/blob/992c7c565d30ff9dc92dc09eeca2d054cd24ad46/net-dns/maradns/maradns-3.5.0020.ebuild
It's to do with the unconventional Makefile. Probably something like running all those commands together only uses the last one's exit code for the rule? Not sure, I haven't played with it. I suspect if you run 'make' manually with those *FLAGS set, it'll exit with exit code 0 (i.e. no failure).
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=02a35ae88a3b84bf2381ffb4244102bdd86f1418 commit 02a35ae88a3b84bf2381ffb4244102bdd86f1418 Author: Eli Schwartz <eschwartz93@gmail.com> AuthorDate: 2024-03-03 05:03:44 +0000 Commit: Sam James <sam@gentoo.org> CommitDate: 2024-03-03 05:51:12 +0000 net-dns/maradns: mark as LTO-unsafe Closes: https://bugs.gentoo.org/861293 Signed-off-by: Eli Schwartz <eschwartz93@gmail.com> Signed-off-by: Sam James <sam@gentoo.org> net-dns/maradns/maradns-3.5.0022.ebuild | 7 ++++++- net-dns/maradns/maradns-3.5.0036.ebuild | 7 ++++++- 2 files changed, 12 insertions(+), 2 deletions(-)
Upstream here. The issue has been fixed upstream in https://github.com/samboy/MaraDNS/commit/d828cdf60f50272fa826ca2e5244e6d5a9e7f737 I have been wanting to have compile time flags to make sure my int_fast32_t variables were consistent everywhere; older compilers would not find those glitches (since the two types are the same right now) so I considered it a non-issue until GCC had some obscure compile time flags to catch those issues.
(In reply to Sam Trenholme from comment #6) > Upstream here. The issue has been fixed upstream in > https://github.com/samboy/MaraDNS/commit/ > d828cdf60f50272fa826ca2e5244e6d5a9e7f737 > > I have been wanting to have compile time flags to make sure my int_fast32_t > variables were consistent everywhere; older compilers would not find those > glitches (since the two types are the same right now) so I considered it a > non-issue until GCC had some obscure compile time flags to catch those > issues. Thank you! Yeah, LTO has turned out to be a goldmine for this sort of thing, because of the better diagnostics it can produce.
