I'm getting a stack-buffer-overflow when starting a new game on Fellowships with 3 normal AIs:

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==22145==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7fff62131050 at pc 0x0000015ccb20 bp 0x7fff62130950 sp 0x7fff62130940
WRITE of size 4 at 0x7fff62131050 thread T0
    #0 0x15ccb1f in DefaultAI::update_buildable_field(Widelands::BuildableField&) /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/ai/defaultai.cc:1885
    #1 0x15c5d4b in DefaultAI::update_all_not_buildable_fields() /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/ai/defaultai.cc:1245
    #2 0x15bd7e0 in DefaultAI::think() /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/ai/defaultai.cc:341
    #3 0x1234e66 in GameHost::think() /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/network/gamehost.cc:730
    #4 0xfc8741 in Widelands::Game::think() /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/logic/game.cc:546
    #5 0x13d8160 in InteractiveBase::think() /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/wui/interactive_base.cc:387
    #6 0x12ea477 in UI::Panel::do_think() /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/ui_basic/panel.cc:455
    #7 0x12e886c in UI::Panel::do_run() /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/ui_basic/panel.cc:181
    #8 0xddfdf9 in UI::Panel::Returncodes UI::Panel::run<UI::Panel::Returncodes>() /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/ui_basic/panel.h:99
    #9 0xfc81d4 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&) /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/logic/game.cc:523
    #10 0x1233d42 in GameHost::run() /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/network/gamehost.cc:672
    #11 0xdd2f60 in WLApplication::mainmenu_multiplayer() /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/wlapplication.cc:1200
    #12 0xdd1fd6 in WLApplication::mainmenu() /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/wlapplication.cc:1040
    #13 0xdcc902 in WLApplication::run() /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/wlapplication.cc:439
    #14 0xdc9960 in main /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/main.cc:49
    #15 0x7f62e043282f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2082f)
    #16 0xdc9828 in _start (/home/bratzbert/sources/widelands/ai_blocked_cosideration/widelands+0xdc9828)

Address 0x7fff62131050 is located in stack of thread T0 at offset 1264 in frame
    #0 0x15c5eef in DefaultAI::update_buildable_field(Widelands::BuildableField&) /home/bratzbert/sources/widelands/ai_blocked_cosideration/src/ai/defaultai.cc:1262

  This frame has 16 object(s):
    [32, 33) 'find_open_water'
    [96, 98) 'nearest_distance'
    [160, 162) 'actual_distance'
    [224, 228) 'unused1'
    [288, 296) 'find_water'
    [352, 368) 'find_unowned_walkable'
    [416, 432) 'find_enemy_owned_walkable'
    [480, 496) 'find_unowned_buildable'
    [544, 560) 'fse'
    [608, 632) 'find_unowned_mines_pots'
    [672, 696) 'find_unowned_iron_mines'
    [736, 760) 'find_ally'
    [800, 824) 'found_buildable_fields'
    [864, 912) 'mr'
    [960, 992) '<unknown>'
    [1024, 1264) 'score_parts' <== Memory access at offset 1264 overflows this variable