Bug#811842: mona: FTBFS with GCC 6: no match for

[Martin Michlmayr]

Package: mona
Version: 1.4-15-1.1
Severity: important
User: debian-gcc at lists.debian.org
Usertags: ftbfs-gcc-6 gcc-6-no-match

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++ -DHAVE_CONFIG_H -I. -I..  -I ../BDD -Wdate-time -D_FORTIFY_SOURCE=2  -g -O2 -fstack-protector-strong -Wformat -Werror=format-security -fgnu89-inline -O3 -DNDEBUG -Wall -c -o mona-lib.o `test -f 'lib.cpp' || echo './'`lib.cpp
> cc1plus: warning: command line option '-fgnu89-inline' is valid for C/ObjC but not for C++
> lib.cpp: In member function 'bool AutLib::fileExists(char*)':
> lib.cpp:286:12: error: no match for 'operator!=' (operand types are 'std::ifstream {aka std::basic_ifstream<char>}' and 'int')
>    return s != 0;
>           ~~^~~~
> 
> lib.cpp:286:12: note: candidate: operator!=(int, int) <built-in>
> lib.cpp:286:12: note:   no known conversion for argument 1 from 'std::ifstream {aka std::basic_ifstream<char>}' to 'int'
> In file included from /usr/include/c++/6/bits/locale_facets.h:48:0,
>                  from /usr/include/c++/6/bits/basic_ios.h:37,
>                  from /usr/include/c++/6/ios:44,
>                  from /usr/include/c++/6/istream:38,
>                  from /usr/include/c++/6/fstream:38,
>                  from lib.cpp:21:
> /usr/include/c++/6/bits/streambuf_iterator.h:210:5: note: candidate: template<class _CharT, class _Traits> bool std::operator!=(const std::istreambuf_iterator<_CharT, _Traits>&, const std::istreambuf_iterator<_CharT, _Traits>&)
>      operator!=(const istreambuf_iterator<_CharT, _Traits>& __a,
>      ^~~~~~~~
> 
> /usr/include/c++/6/bits/streambuf_iterator.h:210:5: note:   template argument deduction/substitution failed:
> lib.cpp:286:15: note:   'std::ifstream {aka std::basic_ifstream<char>}' is not derived from 'const std::istreambuf_iterator<_CharT, _Traits>'
>    return s != 0;
>                ^
> 
> In file included from /usr/include/c++/6/bits/ios_base.h:46:0,
>                  from /usr/include/c++/6/ios:42,
>                  from /usr/include/c++/6/istream:38,
>                  from /usr/include/c++/6/fstream:38,
>                  from lib.cpp:21:
> /usr/include/c++/6/system_error:323:3: note: candidate: bool std::operator!=(const std::error_condition&, const std::error_condition&)
>    operator!=(const error_condition& __lhs,
>    ^~~~~~~~
> 
> /usr/include/c++/6/system_error:323:3: note:   no known conversion for argument 1 from 'std::ifstream {aka std::basic_ifstream<char>}' to 'const std::error_condition&'
> /usr/include/c++/6/system_error:319:3: note: candidate: bool std::operator!=(const std::error_condition&, const std::error_code&)
>    operator!=(const error_condition& __lhs, const error_code& __rhs) noexcept
>    ^~~~~~~~
> 
> /usr/include/c++/6/system_error:319:3: note:   no known conversion for argument 1 from 'std::ifstream {aka std::basic_ifstream<char>}' to 'const std::error_condition&'
> /usr/include/c++/6/system_error:315:3: note: candidate: bool std::operator!=(const std::error_code&, const std::error_condition&)
>    operator!=(const error_code& __lhs, const error_condition& __rhs) noexcept
>    ^~~~~~~~
> 
> /usr/include/c++/6/system_error:315:3: note:   no known conversion for argument 1 from 'std::ifstream {aka std::basic_ifstream<char>}' to 'const std::error_code&'
> /usr/include/c++/6/system_error:311:3: note: candidate: bool std::operator!=(const std::error_code&, const std::error_code&)
>    operator!=(const error_code& __lhs, const error_code& __rhs) noexcept
>    ^~~~~~~~
> 
> /usr/include/c++/6/system_error:311:3: note:   no known conversion for argument 1 from 'std::ifstream {aka std::basic_ifstream<char>}' to 'const std::error_code&'
> In file included from /usr/include/c++/6/string:52:0,
>                  from /usr/include/c++/6/bits/locale_classes.h:40,
>                  from /usr/include/c++/6/bits/ios_base.h:41,
>                  from /usr/include/c++/6/ios:42,
>                  from /usr/include/c++/6/istream:38,
>                  from /usr/include/c++/6/fstream:38,
>                  from lib.cpp:21:
> /usr/include/c++/6/bits/basic_string.h:5122:5: note: candidate: template<class _CharT, class _Traits, class _Alloc> bool std::operator!=(const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&, const _CharT*)
>      operator!=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
>      ^~~~~~~~