> On 20 Jan 2025, at 19:43, Tamar Christina <tamar.christ...@arm.com> wrote: > >> -----Original Message----- >> From: Tamar Christina <tamar.christ...@arm.com> >> Sent: Friday, January 17, 2025 5:07 PM >> To: Kyrylo Tkachov <ktkac...@nvidia.com>; Richard Sandiford >> <richard.sandif...@arm.com> >> Cc: GCC Patches <gcc-patches@gcc.gnu.org>; nd <n...@arm.com>; Richard >> Earnshaw <richard.earns...@arm.com>; ktkac...@gcc.gnu.org >> Subject: RE: [PATCH]AArch64: Drop ILP32 from default elf multilibs after >> deprecation >> >>> -----Original Message----- >>> From: Kyrylo Tkachov <ktkac...@nvidia.com> >>> Sent: Friday, January 17, 2025 3:10 PM >>> To: Richard Sandiford <richard.sandif...@arm.com> >>> Cc: Tamar Christina <tamar.christ...@arm.com>; GCC Patches <gcc- >>> patc...@gcc.gnu.org>; nd <n...@arm.com>; Richard Earnshaw >>> <richard.earns...@arm.com>; ktkac...@gcc.gnu.org >>> Subject: Re: [PATCH]AArch64: Drop ILP32 from default elf multilibs after >>> deprecation >>> >>> >>> >>>> On 17 Jan 2025, at 14:47, Richard Sandiford <richard.sandif...@arm.com> >>> wrote: >>>> >>>> Tamar Christina <tamar.christ...@arm.com> writes: >>>>>> -----Original Message----- >>>>>> From: Kyrylo Tkachov <ktkac...@nvidia.com> >>>>>> Sent: Friday, January 17, 2025 1:22 PM >>>>>> To: Tamar Christina <tamar.christ...@arm.com> >>>>>> Cc: GCC Patches <gcc-patches@gcc.gnu.org>; nd <n...@arm.com>; Richard >>>>>> Earnshaw <richard.earns...@arm.com>; ktkac...@gcc.gnu.org; Richard >>>>>> Sandiford <richard.sandif...@arm.com> >>>>>> Subject: Re: [PATCH]AArch64: Drop ILP32 from default elf multilibs after >>>>>> deprecation >>>>>> >>>>>> >>>>>> >>>>>>> On 17 Jan 2025, at 14:06, Tamar Christina <tamar.christ...@arm.com> >>> wrote: >>>>>>> >>>>>>>> -----Original Message----- >>>>>>>> From: Kyrylo Tkachov <ktkac...@nvidia.com> >>>>>>>> Sent: Friday, January 17, 2025 1:04 PM >>>>>>>> To: Tamar Christina <tamar.christ...@arm.com> >>>>>>>> Cc: GCC Patches <gcc-patches@gcc.gnu.org>; nd <n...@arm.com>; Richard >>>>>>>> Earnshaw <richard.earns...@arm.com>; ktkac...@gcc.gnu.org; Richard >>>>>>>> Sandiford <richard.sandif...@arm.com> >>>>>>>> Subject: Re: [PATCH]AArch64: Drop ILP32 from default elf multilibs >>>>>>>> after >>>>>>>> deprecation >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>>> On 17 Jan 2025, at 13:56, Tamar Christina <tamar.christ...@arm.com> >>> wrote: >>>>>>>>> >>>>>>>>> Hi All, >>>>>>>>> >>>>>>>>> Following the deprecation of ILP32 *-elf builds fail now due to >>>>>>>>> -Werror on >>> the >>>>>>>>> deprecation warning. This is because on embedded builds ILP32 is >>>>>>>>> part of >>> the >>>>>>>>> default multilib. >>>>>>>>> >>>>>>>>> This patch removed it from the default target as the build would fail >>> anyway. >>>>>>>>> >>>>>>>>> Cross compiled on aarch64-none-elf and build succeeds now. >>>>>>>>> >>>>>>>>> Ok for master? >>>>>>>> >>>>>>>> I was going to say that it’s more common to just announce deprecation >>>>>>>> in >>> the >>>>>>>> documentation/release notes for one release cycle, to give time for >> potential >>>>>> users >>>>>>>> to come forward. >>>>>>>> If we remove the multilib build now we’d be helping the support bitrot >> much >>>>>>>> faster, which would make it harder to restore if such a user does come >>> forward. >>>>>>>> >>>>>>> >>>>>>> The alternative approach would be to suppress the warning during build, >> the >>>>>> downside >>>>>>> is ofcourse that this warning does not have a unique identifier, so I >>>>>>> believe >>> we'd >>>>>> have to >>>>>>> suppress all deprecation warnings: >>>>>>> >>>>>>> cc1: error: '-mabi=ilp32' is deprecated [-Werror=deprecated] >>>>>>> >>>>>>> But could work.. >>>>>>> >>>>>> >>>>>> I think if the warning suppression only happened for the ILP32 multilib >>>>>> build >>> that >>>>>> would be okay. >>>>>> Other deprecation warnings would be caught in the LP64 build >>>>> >>>>> I can make that work by conditionally changing MULTILIB_OPTIONS in >>>>> gcc/config/aarch64/t-aarch64 when it's collecting the options for ILP32. >>>>> >>>>> What do others think? >>>> >>>> To be honest, it seems like a waste of effort to me. If anyone complains >>>> about the removal of the multilib in GCC 15, we can always revert it for >>>> later releases in the GCC 15 series. A reversion like that would >>>> presumably also mean reverting the deprecation, since it wouldn't be >>>> worth reinstating the multilib for one release series only. >>> >>> Ok, let’s get rid of the multilib in this release then. >>> My comment about documenting that in the release notes still stands >> >> Not a problem, Thanks for the discussion, >> >>> I don’t know if we document the ILP32 multilib somewhere. If so, it should >>> be >> updated. >> >> From what I can tell, we've never documented what the default multilib is for >> AArch64. >> There are documentation for other targets but can't find any for AArch64. >> >>> In any case the gcc-15 release notes should also mention this change. >> >> Agreed, we haven't written out release notes yet this year, and I'm waiting >> till >> features >> stabilize a bit. Is it ok if I do this when I publish the remainder? As it >> stands we >> haven't >> documented any Arm or AArch64 changes yet to https://gcc.gnu.org/gcc- >> 15/changes.html >> >> But I've added it to the internal list. > > I realized I wasn't explicit enough here.. but if it ok to document this when > we > do the GCC 15 changes? Or did you want it done now before I commit this fix? >
Ah no, feel free to commit the fix now. Kyrill > Thanks, > Tamar > >> >> Thanks, >> Tamar >> >>> Thanks for handling this. >>> Kyrill >>> >>>> >>>> Thanks, >>>> Richard >
