[PATCH v1 2/2] x86_64: Add {u}int_fast defs ideal for x86_64

[Adam Sampson]

Noah Goldstein via Libc-alpha <libc-alpha@sourceware.org> writes:

> {u}int_fast{16|32} should never use 64-bit types. 64-bit instructions
> often use more code size (REX prefix) and a variety of instructions
> are slower on many implementations (div, bswap, etc...).

Isn't that going to cause ABI breakage in other libraries, though?
For example, the jasper JPEG2000 decoder library uses stdint.h's
uint_fast32_t in its public API, and the HDF5 scientific data library
includes constants for the sizes of various types including *int*fast*.

Thanks,

-- 
Adam Sampson <ats@offog.org>                         <http://offog.org/>