Linus Torvalds writes: (Summary)
But couldn't we make the whole stack pointer clobber be dependent on
CONFIG_FRAME_POINTER?
CONFIG_FRAME_POINTER?
The only reason we do it is to make sure the frame pointer is set up before the inline asm is emitted, but with frame pointers disabled we don't need to.
don't need to.
Or was there some other compiler issue?
Or was there some other compiler issue?
But yes, talking to the compiler people is a good idea anyway. Both the clang ones (marking rsp as an in/out register *really* shouldn't cause them to generate wrong code) and the gcc people (to see if there are other alternatives).
are other alternatives).
Linus
Linus
Linus
CONFIG_FRAME_POINTER?
The only reason we do it is to make sure the frame pointer is set up before the inline asm is emitted, but with frame pointers disabled we don't need to.
don't need to.
Or was there some other compiler issue?
Or was there some other compiler issue?
But yes, talking to the compiler people is a good idea anyway. Both the clang ones (marking rsp as an in/out register *really* shouldn't cause them to generate wrong code) and the gcc people (to see if there are other alternatives).
are other alternatives).
Linus
Linus
Linus