Bug#818816: zynaddsubfx: FTBFS with libc 2.23: 'isnan' was not declared in this scope

[Martin Michlmayr]

Package: zynaddsubfx
Version: 2.5.2-2
Severity: important
User: debian-glibc at lists.debian.org
Usertags: 2.23

This package fails to build with libc6 2.23 (2.23-0experimental0 from
experimental).

> sbuild (Debian sbuild) 0.68.0 (15 Jan 2016) on dl580gen9-02.hlinux
...
> cd /<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/rtosc && /usr/bin/cmake -E cmake_link_script CMakeFiles/message-alignment.dir/link.txt --verbose=1
> /usr/bin/cc  -O2 -g -O2 -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2  -fPIC -std=c99   -Wall -Wextra   -Wl,-z,relro CMakeFiles/message-alignment.dir/test/message-alignment.c.o  -o message-alignment -rdynamic librtosc.a 
> make[3]: Leaving directory '/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu'
> make[3]: Leaving directory '/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu'
> [ 59%] Built target liblo
> [ 59%] Built target message-alignment
> In file included from /<<PKGBUILDDIR>>/src/UI/Fl_EQGraph.cpp:6:0:
> /<<PKGBUILDDIR>>/src/UI/../DSP/FFTwrapper.h: In instantiation of 'std::complex<_Tp> FFTpolar(const _Tp&, const _Tp&) [with _Tp = float]':
> /<<PKGBUILDDIR>>/src/UI/Fl_EQGraph.cpp:158:59:   required from here
> /<<PKGBUILDDIR>>/src/UI/../DSP/FFTwrapper.h:61:18: error: 'isnan' was not declared in this scope
>          if (isnan(__x))
>                   ^
> /<<PKGBUILDDIR>>/src/UI/../DSP/FFTwrapper.h:61:18: note: suggested alternative:
> In file included from /<<PKGBUILDDIR>>/src/UI/Fl_Osc_Widget.H:5:0,
>                  from /<<PKGBUILDDIR>>/src/UI/Fl_EQGraph.H:2,
>                  from /<<PKGBUILDDIR>>/src/UI/Fl_EQGraph.cpp:3:
> /usr/include/c++/5/cmath:641:5: note:   'std::isnan'
>      isnan(_Tp __x)
>      ^
> In file included from /<<PKGBUILDDIR>>/src/UI/Fl_EQGraph.cpp:6:0:
> /<<PKGBUILDDIR>>/src/UI/../DSP/FFTwrapper.h:64:18: error: 'isnan' was not declared in this scope
>          if (isnan(__y))
>                   ^
> /<<PKGBUILDDIR>>/src/UI/../DSP/FFTwrapper.h:64:18: note: suggested alternative:
> In file included from /<<PKGBUILDDIR>>/src/UI/Fl_Osc_Widget.H:5:0,
>                  from /<<PKGBUILDDIR>>/src/UI/Fl_EQGraph.H:2,
>                  from /<<PKGBUILDDIR>>/src/UI/Fl_EQGraph.cpp:3:
> /usr/include/c++/5/cmath:641:5: note:   'std::isnan'
>      isnan(_Tp __x)
>      ^
> src/UI/CMakeFiles/zynaddsubfx_gui.dir/build.make:1185: recipe for target 'src/UI/CMakeFiles/zynaddsubfx_gui.dir/Fl_EQGraph.cpp.o' failed
> make[3]: *** [src/UI/CMakeFiles/zynaddsubfx_gui.dir/Fl_EQGraph.cpp.o] Error 1

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