[RFC] Dealing with TARGET_CPU_CPP_BUILTINS

[Joseph S. Myers]

On Mon, 4 Oct 2010, FX wrote:

> The attached patch is my first attempt to deal with 
> TARGET_CPU_CPP_BUILTINS macros by splitting them into 
> language-independent and C-family parts. This is now more like a 
> demonstration of how I intend to proceed, by creating a new macro 
> TARGET_CPU_CPP_BUILTINS_CFAMILY. Also, it shows how I proceed for the 
> case of targets that employ a worker function (which thus does fully 
> belong to, e.g., i386-c.c anymore).

I don't think you need define_target_specific_builtins as part of the 
public interface to cppbuiltin.c; it will always be called along with 
define_language_independent_builtin_macros so may as well be called 
internally by that function (which could gain an iso_c parameter for that 
purpose).

I suppose calling cpp_define directly in target .c files (and generally 
not having a separate set of preprocessor-using-front-end-hooks) is safe 
in that all front ends are linked with cpplib, though I think the reason 
they are so linked at present is just for the line-map code.

-- 
Joseph S. Myers
joseph@codesourcery.com