Implement support for GCC 9

[GunChleoc]

Building Widelands doesn't work properly with GCC 9. See https://bugs.launchpad.net/widelands/+bug/1830626/comments/11

[Tino (tino79)]

No problem on my machine. Waiting for appveyor: https://ci.appveyor.com/project/widelands-dev/widelands/builds/24985396

[Tino (tino79)]

Sorry, you are right https://bugs.launchpad.net/widelands/+bug/1830626/comments/8

Same problem here. Trying to figure out if it is GCC9 or GLBindings 3.1.

[Tino (tino79)]

My findings:
- Debug builds are fine
- Crash does not depend on Glew/GLBinding
- Release with O2/O1/O0 also segfault

Trace:
(gdb) where
#0 0x000000000073a5ff in FieldsToDraw::reset(Widelands::EditorGameBase const&, Vector2<float> const&, float, RenderTarget*) ()
#1 0x000000000072e84c in MapView::draw_terrain(Widelands::EditorGameBase const&, std::vector<std::pair<std::vector<WorkareaPreviewData, std::allocator<WorkareaPreviewData> >, std::vector<std::vector<Widelands::Coords, std::allocator<Widelands::Coords> >, std::allocator<std::vector<Widelands::Coords, std::allocator<Widelands::Coords> > > > >, std::allocator<std::pair<std::vector<WorkareaPreviewData, std::allocator<WorkareaPreviewData> >, std::vector<std::vector<Widelands::Coords, std::allocator<Widelands::Coords> >, std::allocator<std::vector<Widelands::Coords, std::allocator<Widelands::Coords> > > > > > >, bool, RenderTarget*) ()
#2 0x00000000005542bf in InteractivePlayer::draw_map_view(MapView*, RenderTarget*) ()
#3 0x00000000004fbefa in UI::Panel::do_draw_inner(RenderTarget&) ()
#4 0x00000000004fbe82 in UI::Panel::do_draw(RenderTarget&) ()
#5 0x00000000004fceb4 in UI::Panel::do_run() ()
#6 0x0000000000484785 in Widelands::Game::run(UI::ProgressWindow*, Widelands::Game::StartGameType, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, bool, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) ()
#7 0x000000000048733e in Widelands::Game::run_splayer_scenario_direct(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) ()
#8 0x00000000004080bc in WLApplication::mainmenu_tutorial() ()
#9 0x000000000040b401 in WLApplication::mainmenu() ()
#10 0x000000000040be7a in WLApplication::run() ()
#11 0x0000000000401642 in SDL_main ()
#12 0x00000000004030ec in main_getcmdline ()
#13 0x00000000004013a5 in __tmainCRTStartup ()
    at E:/mingwbuild/mingw-w64-crt-git/src/mingw-w64/mingw-w64-crt/crt/crtexe.c:339
#14 0x00000000004014db in WinMainCRTStartup ()
    at E:/mingwbuild/mingw-w64-crt-git/src/mingw-w64/mingw-w64-crt/crt/crtexe.c:195
(gdb)

[Tino (tino79)]

Just a test with Linux, same segfaults:

https://travis-ci.org/widelands/widelands/builds/550657199

[kaputtnik (franku)]

See also bug 1834244 "Release builds crash on multiplayer lan games" which i have marked as a duplicate to this one.

The crash happens close after:

[...]
Replay writer has started
[sync] Reset
Speicherzugriffsfehler (Speicherabzug geschrieben)

[kaputtnik (franku)]

I have tried to break it down by applying some log output until i found a log which isn't printed anymore. The crash happens some where in this call:

const Vector2f texture_offset =
      to_gl_texture(
      terrains.get(field.fcoords.field->terrain_d()).get_texture(gametime).blit_data())
         .origin();

See: https://bazaar.launchpad.net/~widelands-dev/widelands/trunk/view/head:/src/graphic/gl/terrain_program.cc#L108

I have tried to dissolve this call into several calls, to find out which of them fails, but i wasn't able to do so.

During my testing Address Sanitizer prints always a DEADLYSSIGNAL, output attached.

[GunChleoc (gunchleoc)]

I have attached a branch with a patch that I received from the Fedora packager. Could somebody please test?

[kaputtnik (franku)]

The branch works :-) My gcc-version: gcc (GCC) 9.1.0

Compiled a release build without problems and started a single player game and a multiplayer lan game without a crash. Only started the games without any playing. But since the crash happens during game loading, i think my tests are enough.

[GunChleoc (gunchleoc)]

Migrated to https://github.com/widelands/widelands/issues/596