x86_64-unknown-linux-gnu/sysroot/usr/include/bits/wordsize.h - toolchains/kvm - Git at Google

 /* Determine the wordsize from the preprocessor defines.  */

 #if defined __x86_64__
 # define __WORDSIZE	64
 # define __WORDSIZE_COMPAT32	1
 #else
 # define __WORDSIZE	32
 #endif
	/* Determine the wordsize from the preprocessor defines. */

	#if defined __x86_64__
	# define __WORDSIZE 64
	# define __WORDSIZE_COMPAT32 1
	#else
	# define __WORDSIZE 32
	#endif