On Tue, Jan 03, 2017 at 09:39:36am -0800, David wrote: > I’m running Yosemite, Sierra won’t run on my hardware. > > Does the standard expect an int to be a specific size? I can’t imagine this to be the case. > On Mac ints are 32 bits, as are longs. Unlike Linux where long defaults to 64 bits. Depends: $ uname -a Darwin Old-MBA.local 14.5.0 Darwin Kernel Version 14.5.0: Sun Sep 25 22:07:15 PDT 2016; root:xnu-2782.50.9~1/RELEASE_X86_64 x86_64 $ cat size.c #include int main() { printf("sz(int) = %lu, sz(long) = %lu\n", (unsigned long)sizeof(int), (unsigned long)sizeof(long)); return 0; } $ cc -o size size.c $ ./size sz(int) = 4, sz(long) = 8 $ file size size: Mach-O 64-bit executable x86_64 $ cc -m32 -o size size.c $ ./size sz(int) = 4, sz(long) = 4 $ file size size: Mach-O executable i386 As I recall the same applies on linux for amd64, with the size of logn changing depending upon if one compiles as x86 or amd64. ILP32 vs LP64 DF