Summary: | find a way to backport gcc pr95353 into gcc-10 | ||
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Product: | Gentoo Linux | Reporter: | tt_1 <herrtimson> |
Component: | Current packages | Assignee: | Gentoo Toolchain Maintainers <toolchain> |
Status: | RESOLVED UPSTREAM | ||
Severity: | normal | CC: | sam |
Priority: | Normal | ||
Version: | unspecified | ||
Hardware: | All | ||
OS: | Linux | ||
URL: | https://gcc.gnu.org/PR95353 | ||
See Also: | https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95353 | ||
Whiteboard: | |||
Package list: | Runtime testing required: | --- | |
Bug Depends on: | |||
Bug Blocks: | 762907 | ||
Attachments: | minimal example |
Description
tt_1
2021-01-06 18:24:47 UTC
Created attachment 681562 [details]
minimal example
written by Alexander Grund, member of the s25rttr team
g++-10.2.0 -O3 -Werror -c minimal-example1.cpp
It's a large patch. If it gets backported to gcc-10 branch upstream we will pull it in. Feel free to prod or help at upstream bug report at https://gcc.gnu.org/PR95353. I would like to avoid gentoo-specific backporting of big nontrivial patches to avoid regressions and mmerge problems for future patches. It should be easy to workaround the failure by avoiding -Werror=stringop-overflow on gcc-10. yeah I know that patch is really big, and please not that I never asked for someone to actually pick it up before the backport is merged into gcc-10 by upstream. It is only one of many problems with parts of -O3 optimization it seems, and I'm kind of worried that gcc-10.2.0 will go stable regardless. I would say that bad diagnostic while tedious to deal with is not a stable blocker. I don't think this regression is tied to -O3. Upstream bug report specifically has -O2 example on binutils. Given that -O3 is less tested that default -O2 (for both goo upstream and users' upstreams) it is natural to have more bugs there. The only way to get -O3 better is to test, report and fix bugs in software. But I would also say that -O3-only bugs should not block gcc stabilization either. A decent compromise would be pinging us when it's in. |