attribute mode is unknown (Sun cc)

[Torbjorn Granlund]

Jay K <jay.krell at cornell.edu> writes:

  Eek? I'm confused. So, this compiler, and presumably others, does not support __attribute__(mode).
  What to do?
  What is the #else clause for?
  
An attempt to get the right-sized types that works most of the time,
but it assumes e.g. that "unsigned long" is 32 bits.

(It is not at all pretty, and this code predates GMP's use of autoconf;
we should be able to get these things more neatly fusing autoconf.)

-- 
Torbjörn