Raspberry Pi ARM Assembly crashing on push

I'm currently writing up assembly code to run on the Raspberry Pi Bare Metal, and for some reason, the program crashes when it tries to push a register to the software stack. I'm not pushing anything onerous, but just the number 12 that is contained within the register. The code runs fine when I compile it with fasmarm. I was wondering if anyone had the same problem with running code with the Raspberry Pi emulator as well or not.