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. Thanks, Richard
