qt5 fails to build

[tech-lists]

Hello ports@

system: r313940 11-stable amd64
ports: r434399

I cannot build devel/qt5. I don't have qt4 installed.

Here's the error:

Running configuration tests...
Failed to process makespec for platform
'/usr/local/lib/qt5/mkspecs/freebsd-clang'

Turn on verbose messaging (-v) to see the final report.

===> Script "configure" failed unexpectedly.
Please report the problem to kde at FreeBSD.org [maintainer] and attach the
"/storage/usr/ports/devel/qt5-concurrent/work/qtbase-opensource-src-5.7.1/config.log"
including the output of the failure of your make command. Also, it might
be a good idea to provide an overview of all packages installed on your
system
(e.g. a /usr/local/sbin/pkg-static info -g -Ea).

/usr/local/lib/qt5/mkspecs/freebsd-clang is present and contains the
following:

# ls -lah /usr/local/lib/qt5/mkspecs/freebsd-clang
total 24
drwxr-xr-x 2 root wheel 4B Dec 26 16:16 .
drwxr-xr-x 97 root wheel 101B Dec 26 16:16 ..
-rw-r--r-- 1 root wheel 441B Dec 26 16:16 qmake.conf
-rw-r--r-- 1 root wheel 1.7K Dec 26 16:16 qplatformdefs.h

any ideas?

thanks,
-- 
J.