which assembler should work with iPhone?

[Oranav]

As far as I know the iPhone's executable files are Mach-O format.
Which assembler/linker should compile an asm file into an iPhone executable?
I'm running windows (can use cygwin), and I have terminal on the iPhone.

Thanks

[moppsy]

The GNU iphone tool chain.
Info on building it can be found here.
There might also be some packaged versions around.