[PING**2] [PATCH, libstdc++] Add missing free-standing headers to install rule

[Jonathan Wakely]

On 22/03/16 18:29 +0000, Bernd Edlinger wrote:
>Yes. Maybe changing concept_check.h would be better, because
>I see 3 different instances of bits/c++config.h:
>
>$prefix/arm-eabi/include/c++/6.0.0/arm-eabi/fpu/bits/c++config.h
>$prefix/arm-eabi/include/c++/6.0.0/arm-eabi/bits/c++config.h
>$prefix/arm-eabi/include/c++/6.0.0/arm-eabi/thumb/bits/c++config.h

But they're all generated from the same include/bits/c++config in the
source tree, so that shouldn't matter.

>while I only see one use of _GLIBCXX_CONCEPT_CHECKS:
>$prefix/arm-eabi/include/c++/6.0.0/bits/concept_check.h

I'm fine with changing it there. We should also document that the
macro doesn't do anything for freestanding implementations.