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charset="utf-8" As noted (and fixed) a couple of times in the past, "=3D@cc" outputs and clobbering of "cc" don't work well together. The compiler appears to mean to reject such, but doesn't - in its upstream form - quite manage to yet for "cc". Furthermore two similar macros don't clobber "cc", and clobbering "cc" is pointless in asm()-s for x86 anyway - the compiler always assumes status flags to be clobbered there. Fixes: 989b5db215a2 ("x86/uaccess: Implement macros for CMPXCHG on user add= resses") Signed-off-by: Jan Beulich --- The change I continue to carry locally actually allows specifying that "cc" is _not_ clobbered; it only happens to improve detection of bad situations like the one here. --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -439,7 +439,7 @@ do { \ [ptr] "+m" (*_ptr), \ [old] "+a" (__old) \ : [new] ltype (__new) \ - : "memory", "cc"); \ + : "memory"); \ if (unlikely(__err)) \ goto label; \ if (unlikely(!success)) \