On Wed, May 27, 2020 at 11:12:23AM +0200, Laszlo Ersek wrote: > On 05/26/20 16:37, Leif Lindholm wrote: > > On Sat, May 23, 2020 at 00:09:52 +0200, Ard Biesheuvel wrote: > >>>>> diff --git a/MdePkg/Include/AArch64/ProcessorBind.h > >>>>> b/MdePkg/Include/AArch64/ProcessorBind.h > >>>>> index 896bf273ac7a..a3ca8f09e51c 100644 > >>>>> --- a/MdePkg/Include/AArch64/ProcessorBind.h > >>>>> +++ b/MdePkg/Include/AArch64/ProcessorBind.h > >>>>> @@ -24,6 +24,17 @@ > >>>>> #pragma pack() > >>>>> #endif > >>>>> +#if defined(__GNUC__) && !defined(__clang__) > >>>>> + > >>>>> +// > >>>>> +// Disable GCC outline atomics > >>>>> +// Link: https://bugzilla.tianocore.org/show_bug.cgi?id=2723 > >>>>> +// > >>>>> +#if __GNUC__ > 10 || (__GNUC__ == 10 && __GNUC_MINOR__ >= 2) > >>>>> +#pragma GCC target "no-outline-atomics" > >>>>> +#endif > >>>>> +#endif > >>>>> + > >>>>> #if defined(_MSC_EXTENSIONS) > >>>>> // > >>>> > >>>> Reviewed-by: Laszlo Ersek <ler...@redhat.com> > >>>> > >>>> But I think it should be merged later, after GCC 10.2 is out. > >>>> > >>>> (Obviously I don't "insist" that we follow this approach, I'm just OK > >>>> with it.) > >>> > >>> Oh and I think both this patch and the assembly language implementation > >>> for the atomics should be delayed after the stable tag. gcc-10 is a new > >>> toolchain; so even if we don't introduce a new toolchain tag such as > >>> GCC10 for it, whatever we do in order to make it work, that's feature > >>> enablement in my book. > >> > >> Works for me. By the time the next stable tag comes around, early adopters > >> that are now on GCC 10.1 will likely have moved to 10.2 by that time, and > >> so > >> we may not need the assembly patch at all. > > > > I'm not ecstatic that we'll be releasing the first stable tag known to > > break with current toolchains. > > If this breakage affects "current toolchains", then why was > <https://bugzilla.tianocore.org/show_bug.cgi?id=2723> only reported on > 2020-May-19, four days into the soft feature freeze? > > > This isn't just affecting random crazies pulling latest toolchains > > down, but people using their distro defaults (native or cross). > > ... "people using their distro defaults" to *not* build upstream edk2 > until 2020-May-19, apparently. > openSUSE Tumbleweed is going to change the default gcc version to 10. I actually wrote a workaround patch to add "-mno-outline-atomics" and apply it conditionally in the rpm spec file. Anyway, we can live with the workaround, so it's not intolerant to me if the intrinsics patch is not included.
> > I don't recall if 10.1 ended up being default in F32, but it was > > definitely included. In Arch, it does appear default. > > > > Debian/Ubuntu are unaffected in their stable releases. > > > > I agree it's a transitional issue, but I would really prefer to have > > the intrinsics included in the release. > > OK, let's delay the release then, by a few days. I agree the present > patch may qualify as a bugfix, but the other patch with the assembly > language intrinsics doesn't. If it's really that important to have in > the upcoming stable tag, then it's worth delaying the tag for. I'm fine > delaying the release for it; it wouldn't be without precedent. > > Also, I think Ard's assembly language patch needs a Tested-by from Gary > at the least (reporter of TianoCore#2723). Please reach out to him in > that thread. > > ... More precisely, please *ping* Gary for a Tested-by in that thread, > because Ard CC'd him from the start, and even credited Gary in the > commit message. > I thought the patch would be abondoned so didn't try it. Will test it soon. Cheers, Gary Lin > Thanks, > Laszlo > > > > -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#60332): https://edk2.groups.io/g/devel/message/60332 Mute This Topic: https://groups.io/mt/74396053/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
