# Architecture macros and endianess

Hello, I would like to know if there exists some macros for the compiler.
Like the following:

aarch64
arm
i486

And I would like to know the endianess of the machine architectures. I guess all are little endian?
Is there a macro for 32bit and 64bit and a BYTE_ORDER macro?

Yes, all are little-endian… but you could use the `__BYTE_ORDER__` macro for that.
You can use `__i386__`, `__x86_64__` and `__aarch64__`… or maybe the size of the size type is more relevant for your needs.