RFC: adding knowledge of the int_fastN_t types to the compiler

[FX Coudert]

> I suggest runtime-variable values depending on a
> target-independent macro such as LONG_TYPE_SIZE.  Also remember the
> various GNU/Linux targets that do not use config/linux.h (alpha,  
> rs6000,
> sparc).

Thanks for both hints, I'll update the patch.

> Note that the size is not enough for implementing <stdint.h>, you  
> need the
> actual type as well to get C++ mangling right.  So I suggest using
> type-name strings as is done for the other standard typedefs

That raises a question: darwin has, for example, in its system headers:

typedef signed char           int8_t;
[...]
/* 7.18.1.3 Fastest-width integer types */
typedef int8_t            int_fast8_t;
typedef int16_t          int_fast16_t;

To do the right thing, do I have to #define INT_FAST8_TYPE in  
darwin.h to be "int8_t", or "signed char"? I'd go for the second, but  
as I know nothing about C++, I'd like to be sure :)

Thanks,
FX

-- 
François-Xavier Coudert
http://www.homepages.ucl.ac.uk/~uccafco/