On Wed, Jul 24, 2024, at 12:31, Anshuman Khandual wrote: > --- a/include/uapi/asm-generic/bitsperlong.h > +++ b/include/uapi/asm-generic/bitsperlong.h > @@ -28,4 +28,8 @@ > #define __BITS_PER_LONG_LONG 64 > #endif > > +#ifndef __BITS_PER_U128 > +#define __BITS_PER_U128 128 > +#endif I would hope we don't need this definition. Not that it hurts at all, but __BITS_PER_LONG_LONG was already kind of pointless since we don't run on anything else and __BITS_PER_U128 clearly can't have any other sensible definition than a plain 128. > #define __AC(X,Y) (X##Y) > #define _AC(X,Y) __AC(X,Y) > #define _AT(T,X) ((T)(X)) > +#define _AC128(X) ((unsigned __int128)(X)) I just tried using this syntax and it doesn't seem to do what you expected. gcc silently truncates the constant to a 64-bit value here, while clang fails the build. See also https://godbolt.org/z/rzEqra7nY https://stackoverflow.com/questions/63328802/unsigned-int128-literal-gcc The __GENMASK_U128() macro however seems to work correctly since you start out with a smaller number and then shift it after the type conversion. Arnd
