Bug#866988: lordsawar FTBFS: bigmap.cpp:70:16: error: no match for 'operator==' (operand types are 'Cairo::RefPtr<Cairo::Surface>' and 'bool')

[Adrian Bunk]

Source: lordsawar
Version: 0.3.1-1
Severity: serious
Tags: buster sid

Some recent change in unstable makes lordsawar FTBFS:

https://tests.reproducible-builds.org/debian/history/lordsawar.html
https://tests.reproducible-builds.org/debian/rb-pkg/unstable/amd64/lordsawar.html

...
bigmap.cpp: In destructor 'virtual BigMap::~BigMap()':
bigmap.cpp:70:16: error: no match for 'operator==' (operand types are 'Cairo::RefPtr<Cairo::Surface>' and 'bool')
     if (buffer == true)
         ~~~~~~~^~~~~~~
bigmap.cpp:70:16: note: candidate: operator==(int, int) <built-in>
bigmap.cpp:70:16: note:   no known conversion for argument 1 from 'Cairo::RefPtr<Cairo::Surface>' to 'int'
In file included from /usr/include/cairomm-1.0/cairomm/device.h:24:0,
                 from /usr/include/cairomm-1.0/cairomm/surface.h:39,
                 from /usr/include/gdkmm-3.0/gdkmm/pixbuf.h:39,
                 from /usr/include/gdkmm-3.0/gdkmm/dragcontext.h:30,
                 from /usr/include/gtkmm-3.0/gtkmm.h:90,
                 from bigmap.h:29,
                 from bigmap.cpp:27:
/usr/include/cairomm-1.0/cairomm/refptr.h:397:6: note: candidate: bool Cairo::RefPtr<T_CppObject>::operator==(const Cairo::RefPtr<T_CppObject>&) const [with T_CppObject = Cairo::Surface]
 bool RefPtr<T_CppObject>::operator==(const RefPtr<T_CppObject>& src) const noexcept
      ^~~~~~~~~~~~~~~~~~~
...