moving <limits> bits to config/cpu

[Mark Mitchell]

> The (admittedly baroque) way that gcc handles its config files might help
> us here.  If configure.* sets LIMITSH to not a single file but rather
> a list of files which are then concatenated to form limits.h, then the
> OS/limits.h can override the CPU/limits.h.

FWIW, what I think makes sense is that you put the "usual" definitions
for an architecture in cpu/limits.h.  Then, if that's not right for
your OS, you turn off the use of cpu/limits.h in the configury stuff,
and put the stuff you need in yours os_defines.h, or os/limits.h,
or whatever.

My two cents,

-- 
Mark Mitchell                mark@codesourcery.com
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