Bug#811805: gfan: FTBFS with GCC 6: error: reference is ambiguous

[Martin Michlmayr]

Package: gfan
Version: 0.5+dfsg-5
Severity: important
User: debian-gcc at lists.debian.org
Usertags: ftbfs-gcc-6 gcc-6-reference-ambiguous

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++ -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -fstack-protector-strong -Wformat -Werror=format-security -DGMPRATIONAL -Wuninitialized      -c app_secondaryfan.cpp
> app_secondaryfan.cpp: In member function 'virtual int SecondaryFanApplication::main()':
> app_secondaryfan.cpp:310:5: error: reference to 'rank' is ambiguous
>   if(rank(A)!=A.getHeight())
>      ^~~~
> 
> In file included from symmetriccomplex.h:11:0,
>                  from symmetrictraversal.h:4,
>                  from enumeration.h:69,
>                  from reversesearch.h:4,
>                  from app_secondaryfan.cpp:8:
> matrix.h:150:5: note: candidates are: int rank(const IntegerMatrix&)
>  int rank(IntegerMatrix const &m);
>      ^~~~
> 
> In file included from /usr/include/c++/6/bits/move.h:57:0,
>                  from /usr/include/c++/6/bits/stl_pair.h:59,
>                  from /usr/include/c++/6/bits/stl_algobase.h:64,
>                  from /usr/include/c++/6/bits/char_traits.h:39,
>                  from /usr/include/c++/6/string:40,
>                  from parser.h:4,
>                  from app_secondaryfan.cpp:1:
> /usr/include/c++/6/type_traits:1471:12: note:                 template<class> struct std::rank
>      struct rank
>             ^~~~
> 
> app_secondaryfan.cpp:345:8: error: reference to 'rank' is ambiguous
>      if(rank(A)!=A.getHeight())
>         ^~~~
> 
> In file included from symmetriccomplex.h:11:0,
>                  from symmetrictraversal.h:4,
>                  from enumeration.h:69,
>                  from reversesearch.h:4,
>                  from app_secondaryfan.cpp:8:
> matrix.h:150:5: note: candidates are: int rank(const IntegerMatrix&)
>  int rank(IntegerMatrix const &m);
>      ^~~~
> 
> In file included from /usr/include/c++/6/bits/move.h:57:0,
>                  from /usr/include/c++/6/bits/stl_pair.h:59,
>                  from /usr/include/c++/6/bits/stl_algobase.h:64,
>                  from /usr/include/c++/6/bits/char_traits.h:39,
>                  from /usr/include/c++/6/string:40,
>                  from parser.h:4,
>                  from app_secondaryfan.cpp:1:
> /usr/include/c++/6/type_traits:1471:12: note:                 template<class> struct std::rank
>      struct rank
>             ^~~~
> 
> Makefile:438: recipe for target 'app_secondaryfan.o' failed
> make[1]: *** [app_secondaryfan.o] Error 1

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