> > There are two ways to fix the warnings: > > > > 1. get rid of the thunks and call the C functions directly; or > > No. Not until gcc learns about per-function callibg conventions (so that it > can > be marked as not clobbering registers).
It does already for static functions in 5.x (with -fipa-ra). And with LTO it can be used even somewhat globally. Even older version supported it, for only for x86->SSE on 32bit, which is useless for the kernel. But the new IPA-RA propagates which registers are clobbered. That said it will probably be a long time until we can drop support for older compilers. So for now the manual method is still needed. -Andi
