Bug#812034: klick: FTBFS with GCC 6: needed for in-class initialization

[Martin Michlmayr]

Package: klick
Version: 0.12.2-2
Severity: important
User: debian-gcc at lists.debian.org
Usertags: ftbfs-gcc-6

This package fails to build with GCC 6.  GCC 6 has not been released
yet, but it's expected that GCC 6 will become the default compiler for
stretch.

Note that only the first error is reported; there might be more.  You
can find a snapshot of GCC 6 in experimental.  To build with GCC 6,
you can set CC=gcc-6 CXX=g++-6 explicitly.

You may be able to find out more about this issue at
https://gcc.gnu.org/gcc-6/changes.html

> sbuild (Debian sbuild) 0.67.0 (26 Dec 2015) on dl580gen9-02.hlinux
...
> g++ -o src/klick.o -c -Wdate-time -D_FORTIFY_SOURCE=2 -g -W -Wall -DVERSION=\"0.12.2\" -DDATA_DIR=\"/usr/share/klick\" -DHAVE_SNDFILE_OGG -DENABLE_OSC -DENABLE_TERMINAL -DENABLE_RUBBERBAND src/klick.cc
> In file included from src/klick.cc:26:0:
> src/metronome_map.hh:51:42: error: 'constexpr' needed for in-class initialization of static data member 'const double MetronomeMap::TICKS_PER_BEAT' of non-integral type [-fpermissive]
>      static double const TICKS_PER_BEAT = 1920.0;
>                                           ^~~~~~
> 
> In file included from src/klick.cc:28:0:
> src/metronome_simple.hh:62:38: error: 'constexpr' needed for in-class initialization of static data member 'const float MetronomeSimple::MAX_TAP_AGE' of non-integral type [-fpermissive]
>      static float const MAX_TAP_AGE = 3.0;
>                                       ^~~
> 
> src/metronome_simple.hh:63:35: error: 'constexpr' needed for in-class initialization of static data member 'const float MetronomeSimple::TAP_DIFF' of non-integral type [-fpermissive]
>      static float const TAP_DIFF = 0.2;
>                                    ^~~
> 
> scons: *** [src/klick.o] Error 1
> scons: building terminated because of errors.

-- 
Martin Michlmayr
Linux for HPE Helion, Hewlett Packard Enterprise