qmk-firmware/lib/fnv/have_ulong64.c

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/*
* have_ulong64 - Determine if we have a 64 bit unsigned long long
*
* usage:
* have_ulong64 > longlong.h
*
* Not all systems have a 'long long type' so this may not compile on
* your system.
*
* This prog outputs the define:
*
* HAVE_64BIT_LONG_LONG
* defined ==> we have a 64 bit unsigned long long
* undefined ==> we must simulate a 64 bit unsigned long long
*/
/*
*
* Please do not copyright this code. This code is in the public domain.
*
* LANDON CURT NOLL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO
* EVENT SHALL LANDON CURT NOLL BE LIABLE FOR ANY SPECIAL, INDIRECT OR
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
* USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
* OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*
* By:
* chongo <Landon Curt Noll> /\oo/\
* http://www.isthe.com/chongo/
*
* Share and Enjoy! :-)
*/
/*
* have the compiler try its hand with unsigned and signed long longs
*/
#if ! defined(NO64BIT_LONG_LONG)
unsigned long long val = 1099511628211ULL;
#endif /* NO64BIT_LONG_LONG */
int
main(void)
{
/*
* ensure that the length of long long val is what we expect
*/
#if defined(NO64BIT_LONG_LONG)
printf("#undef HAVE_64BIT_LONG_LONG\t/* no */\n");
#else /* NO64BIT_LONG_LONG */
if (val == 1099511628211ULL && sizeof(val) == 8) {
printf("#define HAVE_64BIT_LONG_LONG\t/* yes */\n");
}
#endif /* NO64BIT_LONG_LONG */
/* exit(0); */
return 0;
}