wide-int branch now up for public comment and review

[Richard Sandiford]

Thanks for doing this.  I haven't had chance to look at the branch yet
(hope to soon), but the results on mips64-linux-gnu look pretty good:

  http://gcc.gnu.org/ml/gcc-testresults/2013-08/msg02033.html

The only failures that stand out as being possibly wide-int-related are:

  FAIL: gcc.dg/fixed-point/int-warning.c  (test for warnings, line ...)

which isn't something that x86_64-linux-gnu or powerpc64-linux-gnu
would test AFAIK.  Haven't had chance to look into why it's failing yet,
but FWIW it's a compile-only test so should be reproducable with a cc1 cross.

I'll run a test with the corresponding trunk version too.

Thanks,
Richard