* Kyrylo Tkachov: > Hi Florian, > >> -----Original Message----- >> From: Gcc <gcc-boun...@gcc.gnu.org> On Behalf Of Florian Weimer via Gcc >> Sent: 29 April 2020 13:33 >> To: gcc@gcc.gnu.org >> Cc: nmeye...@amzn.com >> Subject: Should ARMv8-A generic tuning default to -moutline-atomics >> >> Distributions are receiving requests to build things with >> -moutline-atomics: >> >> <https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=956418> >> >> Should this be reflected in the GCC upstream defaults for ARMv8-A >> generic tuning? It does not make much sense to me if every distribution >> has to overide these flags, either in their build system or by patching >> GCC. > > I don't think this is a "tuning" decision as such, it is a useful > feature for deploying LSE in a backwards-compatible manner.
To me, the Debian bug report suggests that it's closer to a workaround for a silicon quirk on some platforms. The performance impact of not using LSE on these platforms seems that severe unfortuantely. That's why I thought it might be appropriate for generic tuning. > I would support a GCC configure option that would allow distributions > to default GCC to it. That would be better than no support at all for this in GCC. Thanks, Florian
