cursor.h:137 error: field ‘Ident’ has incomplete type ‘std::string’ {aka ‘std::__cxx11::basic_string<char>’}

[egberts]

On Debian 12, pulling the latest main branch (3941a355), cmake, then make, I get the following error:

src/include/cursor.h:137:21: error: field ‘Ident’ has incomplete type ‘std::string’ {aka ‘std::__cxx11::basic_string<char>’}
  137 |         std::string Ident;  /// Identifier to reference it
      |                     ^~~~~

To recreate this on an unpatched Debian 12 using gcc 12.2.0 toolchain:

$ git clone --recurse-submodules https://github.com/Wargus/strratagum
$ cd stratagum
$ mkdir build
$ cmake ..
$ VERBOSE=defined make

<snipped out the largely successful error-free, warning-free compilation ...>

make[2]: Entering directory '/home/user/admin/games/stratagus/build'
cd /home/user/admin/games/stratagus/build && /usr/bin/cmake -E cmake_depends "Unix Makefiles" /home/user/admin/games/stratagus /home/user/admin/games/stratagus /home/user/admin/games/stratagus/build /home/user/admin/games/stratagus/build /home/user/admin/games/stratagus/build/CMakeFiles/stratagus_lib.dir/DependInfo.cmake --color=
Dependencies file "CMakeFiles/stratagus_lib.dir/src/ui/mouse.cpp.o.d" is newer than depends file "/home/user/admin/games/stratagus/build/CMakeFiles/stratagus_lib.dir/compiler_depend.internal".
Consolidate compiler generated dependencies of target stratagus_lib
make[2]: Leaving directory '/home/user/admin/games/stratagus/build'
make  -f CMakeFiles/stratagus_lib.dir/build.make CMakeFiles/stratagus_lib.dir/build
make[2]: Entering directory '/home/user/admin/games/stratagus/build'
[ 19%] Building CXX object CMakeFiles/stratagus_lib.dir/src/ui/mouse.cpp.o

/usr/bin/c++ -DDYNAMIC_LOAD -DHAVE_GETOPT -DHAVE_STRNLEN -DPIXMAPS=\"/usr/local/share/pixmaps\" -DUSE_BZ2LIB -DUSE_LINUX -DUSE_OPENMP -DUSE_VORBIS -DUSE_ZLIB -I/home/user/admin/games/stratagus/src/include -I/home/user/admin/games/stratagus/src/third_party -I/home/user/admin/games/stratagus/build -I/home/user/admin/games/stratagus/third-party/mdns -I/home/user/admin/games/stratagus/third-party/spiritless_po/include -isystem /usr/include/lua5.1 -isystem /usr/include/SDL2 -isystem /home/user/admin/games/stratagus/third-party/guichan/include -g -ggdb -fsigned-char -fPIC -fopenmp -std=gnu++17 -MD -MT CMakeFiles/stratagus_lib.dir/src/ui/mouse.cpp.o -MF CMakeFiles/stratagus_lib.dir/src/ui/mouse.cpp.o.d -o CMakeFiles/stratagus_lib.dir/src/ui/mouse.cpp.o -c /home/user/admin/games/stratagus/src/ui/mouse.cpp
In file included from /home/user/admin/games/stratagus/src/ui/mouse.cpp:43:
/home/user/admin/games/stratagus/src/include/cursor.h:137:21: error: field ‘Ident’ has incomplete type ‘std::string’ {aka ‘std::__cxx11::basic_string<char>’}
  137 |         std::string Ident;  /// Identifier to reference it
      |                     ^~~~~
In file included from /usr/include/c++/12/iosfwd:39,
                 from /usr/include/c++/12/bits/shared_ptr.h:52,
                 from /usr/include/c++/12/memory:77,
                 from /home/user/admin/games/stratagus/src/include/actions.h:38,
                 from /home/user/admin/games/stratagus/src/include/action/action_build.h:33,
                 from /home/user/admin/games/stratagus/src/ui/mouse.cpp:39:
/usr/include/c++/12/bits/stringfwd.h:72:11: note: declaration of ‘std::string’ {aka ‘class std::__cxx11::basic_string<char>’}
   72 |     class basic_string;
      |           ^~~~~~~~~~~~

Me think that gcc 12.2 finally kicked out the C11 and (some C17) compliance part in 100% full-force

[egberts]

A simple adding the string.h include file into cursor.h appears to fix the compilation problem of this source file mouse.cpp

New code snippet of cursor.h:

/*----------------------------------------------------------------------------
--  Includes
----------------------------------------------------------------------------*/

#include <string>  // new line

#include "sdl2_helper.h"
#include "vec2i.h"

#include <SDL.h>
#include <vector>