[C++ Patch] Fix PR 39475

[Mark Mitchell]

Paolo Carlini wrote:

> at variance with Icc, we weren't enforcing the requirements in Table 33
> of the Draft C++1x standard about the completeness of the types passed
> to the type_trait "builtins".
> 
> Tested x86_64-linux. Ok for mainline?

This is OK in principle, but this comment:

+ /* Checks that a type fulfills the preconditions in Table 33.  */

This should explicitly reference TYPE and should quote the appropriate
bits of the standard -- or paraphrase them -- rather than referring to
Table 33.

OK with that minor change.

Thanks,

-- 
Mark Mitchell
CodeSourcery
mark@codesourcery.com
(650) 331-3385 x713