Messages in this thread | | | From | Linus Torvalds <> | Date | Fri, 24 Jun 2022 11:29:49 -0700 | Subject | Re: [PATCH 0/2] Kconfig: -O3 enablement |
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On Thu, Jun 23 at 7:27:29 PM Arnd Bergmann <arnd@arndb.de> wrote: > > This probably also needs a dependency on !COMPILE_TEST so we don't > report compile-time problems that are specific to -O3.
Honestly, let's just remove -O3 entirely.
Enabling it, and then not even build-testing the result, is just about the *worst* possible case. That's just horrible.
The argument that "but ARC uses it" is not an argument. It was always a bad argument, and ARC needs to just fix whatever it is that made it an issue (likely already fixed with a compiler upgrade).
And there is no way I would ever accept this as a "let people try it" when
- as mentioned, just use KCFLAGS=-O3 if you want to
- -O3 has a *loong* history of generating worse code than -O2
so I will *not* be taking these kinds of patches without some very serious explanations of why -O3 has suddenly become acceptable again.
Those explanations had better be more than "let people try". They should have in-depth actual performance numbers for a real load, not some made-up "bigger is better" logic.
Linus
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