8.12 Assembly Support

Automake includes some support for assembly code. There are two forms of assembler files: normal (‘*.s’) and preprocessed by CPP (‘*.S’).

The variable CCAS holds the name of the compiler used to build assembly code. This compiler must work a bit like a C compiler; in particular it must accept ‘-c’ and ‘-o’. The values of CCASFLAGS and AM_CCASFLAGS (or its per-target definition) is passed to the compilation. For preprocessed files, DEFS, DEFAULT_INCLUDES, INCLUDES, CPPFLAGS and AM_CPPFLAGS are also used.

The autoconf macro AM_PROG_AS will define CCAS and CCASFLAGS for you (unless they are already set, it simply sets CCAS to the C compiler and CCASFLAGS to the C compiler flags), but you are free to define these variables by other means.

Only the suffixes ‘.s’ and ‘.S’ are recognized by automake as being files containing assembly code.