fix libstdc++/47387 AIX ctype mask override

[Paolo Carlini]

On 01/24/2011 07:47 PM, Graham Reed wrote:
> Per bug 47387, the attached patch fixes the problem, found by the
> libstdc++ regression suite, where ctype mask override isn't working. 
> It applies only to AIX.
>
> The existing testcase '22_locale/ctype/is/char/3.cc' is sufficient to
> verify the fix.
>
>    PR libstdc++/47387
>    * config/os/aix/ctype_inline.h: Use _M_table if provided.
>
> I have run the regression suite with this change on
> powerpc-ibm-aix5.3.0.0, verifying 4 multilib combinations: '',
> 'ppc64', 'pthread', and 'pthread/ppc64' in the 4.5.2 release code.
>
Excellent. I think the path is fine for mainline, I can take care of
applying it. Note the ChangeLog entry should mention the touched
functions, thus, I would say, concisely:

    PR libstdc++/47387
    * config/os/aix/ctype_inline.h (ctype<char>::is): Use _M_table if
provided.

Thanks,
Paolo.