[cfe-dev] Removing some built-in __*_TYPE__ macros

[Ken Dyck]

The following built-in macros were once used, but are no longer required
by stdint.h:

  __INTMAX_TYPE__
  __UINTMAX_TYPE__
  __PTRDIFF_TYPE__
  __INTPTR_TYPE__
  __SIZE_TYPE__
  __WCHAR_TYPE__
  __WINT_TYPE__

For the most part, the only references to these macros are in the
preprocessor initialization test case, test/Preprocessor/init.c. A
couple of them, namely __INTPTR_TYPE__ and __SIZE_TYPE__, are used in a
few other tests besides. Provided these references can be removed or
replaced with their standard counterparts (eg. intmax_t), would there be
any objection to removing these definitions from the built-in
definitions? That is, does anybody write code that uses them? And do we
want them to continue doing so?

-Ken