On Fri, Sep 11, 2020 at 1:33 AM Nathan Chancellor <natechancellor@xxxxxxxxx> wrote: > > On Thu, Sep 10, 2020 at 10:51:18PM +0900, Masahiro Yamada wrote: > > The minimal compiler versions, GCC 4.9 and Clang 10 support this flag. > > > > Here is the godbolt: > > https://godbolt.org/z/8T4177 > > > > Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx> > > For what it's worth, the commit that introduced this block is going to > be reverted: > > https://lore.kernel.org/mm-commits/20200903201518.JKrRS%25akpm@xxxxxxxxxxxxxxxxxxxx/ My bad - you are right. This hunk has already gone by Nick's patch. Thanks. > Regardless, it was introduced in LLVM 2.7.0 in commit > f9d41df0930986c52e198292cf875eb5d1761ece. > > Reviewed-by: Nathan Chancellor <natechancellor@xxxxxxxxx> > > > --- > > > > Makefile | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/Makefile b/Makefile > > index 059b36f2ea53..1b6abecc5cab 100644 > > --- a/Makefile > > +++ b/Makefile > > @@ -927,7 +927,7 @@ KBUILD_CFLAGS += -fno-strict-overflow > > # clang sets -fmerge-all-constants by default as optimization, but this > > # is non-conforming behavior for C and in fact breaks the kernel, so we > > # need to disable it here generally. > > -KBUILD_CFLAGS += $(call cc-option,-fno-merge-all-constants) > > +KBUILD_CFLAGS += -fno-merge-all-constants > > > > # for gcc -fno-merge-all-constants disables everything, but it is fine > > # to have actual conforming behavior enabled. > > -- > > 2.25.1 > > > > -- > You received this message because you are subscribed to the Google Groups "Clang Built Linux" group. > To unsubscribe from this group and stop receiving emails from it, send an email to clang-built-linux+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit https://groups.google.com/d/msgid/clang-built-linux/20200910163311.GB3119896%40ubuntu-n2-xlarge-x86. -- Best Regards Masahiro Yamada
