V3 PATCH: numeric_limits<> support, fix PR/3865

[Gabriel Dos Reis]

Neil Booth <neil@daikokuya.co.uk> writes:

| Gabriel Dos Reis wrote:-
| 
| > I like your design better.  Can we agree on implementing that for 3.4
| > rather than 3.3?
| 
| If we do this, let's leave the macros undocumented so that third
| party code doesn't come to rely on them.

I have no problem with that.  I thought gccint.texi was for GCC
developers only and I was "obliged" by some conventions to document
them. 

Does everybody agree I revert the documentation patch?

-- Gaby