* Cyril Hrubis:
As far as I can tell the userspace bits/types.h does exactly the same
check in order to define uint64_t and int64_t, i.e.:
#if __WORDSIZE == 64
typedef signed long int __int64_t;
typedef unsigned long int __uint64_t;
#else
__extension__ typedef signed long long int __int64_t;
__extension__ typedef unsigned long long int __uint64_t;
#endif
The macro __WORDSIZE is defined per architecture, and it looks like the
defintions in glibc sources in bits/wordsize.h match the uapi
asm/bitsperlong.h. But I may have missed something, the code in glibc is
not exactly easy to read.
__WORDSIZE isn't exactly a standard libc macro.
On musl, x86-64 x32 has __WORDSIZE == 64 depending on header-inclusion
order, but that's probably just a bug.
Thanks,
Florian