libstdc++/3720: Problems with num_get

[Benjamin Kosnik]

> 1. Looking at the code, there are two calls to log() per integer
>    input in _M_extract_int() in locale_facets.tcc

These have been made constant.

> 2. You aren't calling test13() from main() in
>    testsuite/27_io/istream_extractor_arith.cc

Fixed.

> 3. Trying the code, input of std::numeric_limits<T>::max() in octal or
>    hex doesn't appear to work for integers, e.g. reading 017777777777
>    into a long on x86 doesn't work, it appears to accept one character
>    too few. Decimal works.

Not quite sure what you mean here, can you provide this problem 
statement in C++ please.

thanks.

benjamin