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bugfix(pathfinder): Fix rare retail pathfinding crashes in forwardInsertionSortRetailCompatible() and putOnClosedList() #3113

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bugfix(pathfinder): Fix rare retail pathfinding crashes in forwardInsertionSortRetailCompatible() and putOnClosedList() #3113

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bugfix(pathfinder): Prevent a retail crash where the head of the clos…
Mauller Aug 3, 2026
c0fc2b6
bugfix(pathfinder): Prevent a retail crash where a pathfindCell has a…
Mauller Aug 3, 2026
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23 changes: 22 additions & 1 deletion Core/GameEngine/Source/GameLogic/AI/AIPathfind.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1125,9 +1125,11 @@ void PathfindCellInfo::forceCleanPathFindCellInfos()

void Pathfinder::forceCleanCells()
{
UnicodeString pathfinderFailoverMessage = TheGameText->FETCH_OR_SUBSTITUTE("GUI:PathfindingCrashPrevented", L"A pathfinding crash was prevented, now switching to the crash fixed pathfinding.");
UnicodeString pathfinderFailoverMessage = TheGameText->FETCH_OR_SUBSTITUTE_FORMAT("GUI:PathfindingCrashPrevented", L"A pathfinding crash was prevented at frame %u, now switching to the crash fixed pathfinding.", TheGameLogic->getFrame());
TheInGameUI->message(pathfinderFailoverMessage);

printf("%ls\n", pathfinderFailoverMessage.str());

TheAudio->addAudioEvent(&TheAudio->getMiscAudio()->m_allCheerSound);

PathfindCellInfo::forceCleanPathFindCellInfos();
Expand Down Expand Up @@ -1727,6 +1729,13 @@ void PathfindCell::forwardInsertionSortRetailCompatible(PathfindCellList& list)
UnsignedInt cellCount = 0;
while (currentCell && cellCount < PATHFIND_CELLS_PER_FRAME && currentCell->m_info->m_totalCost <= m_info->m_totalCost)

@bobtista bobtista Aug 11, 2026

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can currentCell->m_info be null here?

@Mauller Mauller Aug 12, 2026

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Not in the way you are likely thinking.

When cells are initially put onto the list they are externally checked to make sure they have info allocated to them first.

The only time it crashes at this point is if a cell initially put onto the list has dangling next pointers.

{
// Prevent a retail crash where a pathfindCell has an m_info with a dangling nextOpen pointer
if (currentCell->m_info->m_nextOpen && !currentCell->m_info->m_nextOpen->m_cell->m_info)
{
currentCell->m_info->m_nextOpen->m_cell = nullptr;
currentCell->m_info->m_nextOpen = nullptr;
}

cellCount++;
previousCell = currentCell;
currentCell = currentCell->getNextOpen();
Expand Down Expand Up @@ -1976,7 +1985,19 @@ void PathfindCell::putOnClosedList( PathfindCellList &list )
m_info->m_prevOpen = nullptr;
m_info->m_nextOpen = list.m_head ? list.m_head->m_info : nullptr;
if (list.m_head)
#if RETAIL_COMPATIBLE_PATHFINDING
// TheSuperHackers @info This is only here to catch a crash point in the retail compatible pathfinding
// This crash mode occurs due to the closed list head not having an m_info associated with it
// A node cannot be put onto the closed list without an m_info under normal conditions
{
if (list.m_head->m_info)
{
list.m_head->m_info->m_prevOpen = this->m_info;
}
}
#else
list.m_head->m_info->m_prevOpen = this->m_info;
#endif

list.m_head = this;
}
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