There are some predefined macros you would want to use fequently.
However some of them are hard to find, when you want to use them but don’t remember the exact spelling.
So.. let’s briefly list it here.
for Intel (32-bit)
for Intel (64-bit)
for PowerPC (32-bit)
for PowerPC (64-bit)
for Big endian CPU
for Little endian CPU
for The LP64 (64-bit) data model