Am Sonntag, den 07.11.2021, 10:24 +0100 schrieb Florian Weimer: > * Martin Uecker via Gcc: > > > It would be great if somebody could take a look at > > PR96159. > > > > It seems we do not do atomic accesses correctly > > when the alignment is insufficient for a lockfree > > access, but I think we should fall back to a > > library call in this case (as clang does). > > > > This is very unfortunate as it is an important > > functionality to be able to do atomic accesses > > on non-atomic types and it seems there is no way > > to achieve this. > > GCC should probably warn about this, and ensure that objects declared > _Atomic have increased alignment. But adding run-time checks to all > atomic accesses does not make sense. We want to move user code away > from bespoke atomics implementations, and this would be contrary to that > goal.
You do not build trust in your API if you silently create incorrect code. If the alignment is sufficient as guaranteed by the type, clang also does not use a run-time check. Martin
