Re: lang/gcc6, lgamma1(), _GLIBCXX_USE_C99_MATH_TR1 and "'round' is not a member of 'std'"

[maya%netbsd.org@localhost]

On Mon, Sep 03, 2018 at 05:59:29PM +0200, Edgar Fuß wrote:
> I am building 2018Q2 using lang/gcc6 (GCC 6.4.0).
> I got "'round' is not a member of 'std'".
> I found out this is because bits/c++config.h doesn't define 
> _GLIBCXX_USE_C99_MATH_TR1.
> According to a freebsd thread 
> (https://lists.freebsd.org/pipermail/freebsd-current/2014-January/048130.html) 
> GCC does this if libm doesn't contain lgamma1 etc.
> So, while I'm on 6.1, it looks like no NetBSD's libm contains lgamma1.
> Is this true? If no, what do I overlook? If yes, how to resolve it?

I was going to suggest 'use the new libm code', but netbsd 7.0 was also
the point that some compiler defaults were changed, so I don't know how
this works out.

Perhaps force pass the failing configure tests:
MAKE_ENV+=ac_cv_failing_test=yes