Invoking (Using as) (original) (raw)

2 Command-Line Options

This chapter describes command-line options available in _all_versions of the GNU assembler; see Machine Dependent Features, for options specific to particular machine architectures.

If you are invoking as via the GNU C compiler, you can use the ‘-Wa’ option to pass arguments through to the assembler. The assembler arguments must be separated from each other (and the ‘-Wa’) by commas. For example:

gcc -c -g -O -Wa,-alh,-L file.c

This passes two options to the assembler: ‘-alh’ (emit a listing to standard output with high-level and assembly source) and ‘-L’ (retain local symbols in the symbol table).

Usually you do not need to use this ‘-Wa’ mechanism, since many compiler command-line options are automatically passed to the assembler by the compiler. (You can call the GNU compiler driver with the ‘-v’ option to see precisely what options it passes to each compilation pass, including the assembler.)