From: Gao Xiang <[email protected]> commit b344d6a83d01 ("parisc: add support for cmpxchg on u8 pointers") can generate a sparse warningi ("cast truncates bits from constant value"), which has been reported several times [1] [2] [3].
The original code worked as expected, but anyway, let silence such sparse warning as what others did [4]. [1] https://lore.kernel.org/r/[email protected] [2] https://lore.kernel.org/r/[email protected] [3] https://lore.kernel.org/r/202008210829.kvwn7xeh%[email protected] [4] https://lore.kernel.org/r/[email protected] Cc: Liam Beguin <[email protected]> Cc: Helge Deller <[email protected]> Signed-off-by: Gao Xiang <[email protected]> --- arch/parisc/include/asm/cmpxchg.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/parisc/include/asm/cmpxchg.h b/arch/parisc/include/asm/cmpxchg.h index cf5ee9b0b393..84ee232278a6 100644 --- a/arch/parisc/include/asm/cmpxchg.h +++ b/arch/parisc/include/asm/cmpxchg.h @@ -72,7 +72,7 @@ __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new_, int size) #endif case 4: return __cmpxchg_u32((unsigned int *)ptr, (unsigned int)old, (unsigned int)new_); - case 1: return __cmpxchg_u8((u8 *)ptr, (u8)old, (u8)new_); + case 1: return __cmpxchg_u8((u8 *)ptr, old & 0xff, new_ & 0xff); } __cmpxchg_called_with_bad_pointer(); return old; -- 2.20.1
