Im working on a project where speed is a major concern and where I'm also working on alot of 4x4 arrays of chars.

I would like to XOR these chars by grouping them together 4 at a time(by casting), hopefully as a optimization(so the proc is working with its normal 32 bit amount).

Sounds simple but I cant seem to appease the compiler gods.

My code:
Code:
#include <stdio.h>

int main() {
	unsigned char x[4];
	unsigned char y[4];

	x = (unsigned char[4])((unsigned int)x ^ (unsigned int)y);
	
	return 0;
}
gives:
xor.c: In function 'main':
xor.c:7: error: cast specifies array type
Any advice?
Thanks