-spectre list
		Enable spectre mitigations in list (all, ret).
	-trimpath prefix
		Remove prefix from recorded source file paths.
	-v
		Print debug output.

Input language:

The assembler uses mostly the same syntax for all architectures,
the main variation having to do with addressing modes. Input is
run through a simplified C preprocessor that implements #include,
#define, #ifdef/endif, but not #if or ##.