Creating builtin platform specific typedefs

[Steve Ellcey <sje at cup dot hp dot com>]

While reading the thread about creating __int64 types on ia64, I saw a
reference to using record_builtin_type to create a machine specific
builtin type in the same way that using builtin_define creates
predefined symbols or builtin_function creates predefined functions.
But as Jim Wilson noticed, no one uses it this way and there are no uses
of record_builtin_type in any of the platform specific config/* files.

I would like to know if people think it would acceptable as a general
concept to use record_builtin_type as a way to create platform specific
predefined types?  Specifically, I am thinking that if I created a
builtin type of __va_list that was set to the type of __gnuc_va_list
then I might have a shot at removing any need to hack header files on
the HP-UX IA64 platform and that would be a very good thing in my
opinion.

Comments?

Steve Ellcey
sje@cup.hp.com