yasm

Yasm is a complete rewrite of the NASM assembler. It supports multiple
assembler syntaxes (eg, NASM, GAS, etc.) in addition to multiple
output object formats (binary objects, COFF, Win32, ELF32, ELF64) and
even multiple instruction sets (including AMD64). It also has an
optimiser module.

把一个source.asm编译成object.o的用法:

yasm -f elf -o object.o source.asm