Btw the text below is from gcc 3.0.2 cpp parser:
/* Find HOST_WIDEST_INT and set its bit size, type and print macros.
   It will be the largest integer mode supported by the host which may
   (or may not) be larger than HOST_WIDE_INT.  This must appear after
   <limits.h> since we only use `long long' if its bigger than a
   `long' and also if it is supported by macros in limits.h.  For old
   hosts which don't have a limits.h (and thus won't include it in
   stage2 cause we don't rerun configure) we assume gcc supports long
   long.)  Note, you won't get these defined if you don't include
   {ht}config.h before this file to set the HOST_BITS_PER_* macros. */

and the HOST_WIDEST_INT is used for all arithmetic in CPP.

On Thu, 16 May 2002 kuznet@ms2.inr.ac.ru wrote:

Hello!

quoted

echo -e "#if ~0UL == 0xffffffff\nTST\n#endif"|gcc -E -
echo -e "#if ~0UL == 0xffffffffffffffff\nTST\n#endif"|gcc -E -

and the second line displays TST !!

With old good 2.7.2 this worked...

Dave, do you know a theory explaining this change in gcc behavior?

Alexey