Hi Richard, > On Jul 31, 2017, at 11:58 , Richard Earnshaw (lists) > <richard.earns...@arm.com> wrote: > >> Regarding removal of old ABI support, which release were you >> targeting ? >> >> On the VxWorks front, where we adapt to what the system toolchains >> do, it will mean dropping support for VxWorks versions prior to 7, >> which is not so old - couple of years I think. Not the end of the >> world, but an extra release cycle can make a difference. >> >> Is VxWorks alone in this category ? > > Pretty close, I think. The only other ARM port using the old ABI that > I'm aware of is NetBSD. That doesn't use GCC as it's default compiler > these days and even there an EABI port is in use (I suspect Clang > requires it). > > So until I became aware of the VXworks port using the old ABI, I thought > there was only one remaining port - VXworks makes that 2 but both seem > to have a transition plan of sorts.
> I think deprecating in gcc-8 with removal in GCC-9 is probably viable on > that basis, so that's my opening bid. Given that gcc-8 will have a > 2-year support window that means support for the old ABI through to > ~2020, at which point v2 of the EABI will itself be 15 years old. I see, thanks for sharing the plan. For VxWorks, it's really a matter of how long do we want to support versions prior to the most recent one today (VxWorks 7). Vx7 is only two years old, so dropping support in gcc-8 would have been pretty delicate. A year later seems like a fair compromise at this stage. Updating toolchains is usually an involved process, so people switching to gcc-8 would typically only do so months (roughly a year maybe) after it's out. It then seems possible that people really willing to switch toolchains after that might also consider moving to VxWorks >= 7 if not already done. We'll see. Regarding the port evolution, I'm about to post a few updates. A couple of these call for an ARM maintainer approval I think (e.g. addition of a _clear_cache variant to lib1funcs.S). I'll cc you on these specifically. Thanks for your feedback :) With Kind Regards, Olivier
