Initialize reserved names once to avoid race condition

CanOptimizeCallback::isReservedName function may be executed by multiple threads
simultaneously. One of them creates a static but both of them run if statement
and see it's empty because none of them added elements there yet. Both of them
go to the branch where new elements are added doing it without any
synchronization possibly causing SIGSEGV.

CHANGELOG.md

@@ -179,6 +179,7 @@
     Bug #6913: Constant effect enchanted items don't break invisibility
     Bug #6923: Dispose of corpse prevents respawning after load
     Bug #6937: Divided by Nix Hounds quest is broken
+    Bug #7008: Race condition on initializing a vector of reserved node names
     Feature #890: OpenMW-CS: Column filtering
     Feature #1465: "Reset" argument for AI functions
     Feature #2491: Ability to make OpenMW "portable"

components/resource/scenemanager.cpp

@@ -619,6 +619,67 @@ namespace Resource
 
             return node;
         }
+
+        std::vector<std::string> makeSortedReservedNames()
+        {
+            static constexpr std::string_view names[] = {
+                "Head",
+                "Neck",
+                "Chest",
+                "Groin",
+                "Right Hand",
+                "Left Hand",
+                "Right Wrist",
+                "Left Wrist",
+                "Shield Bone",
+                "Right Forearm",
+                "Left Forearm",
+                "Right Upper Arm",
+                "Left Upper Arm",
+                "Right Foot",
+                "Left Foot",
+                "Right Ankle",
+                "Left Ankle",
+                "Right Knee",
+                "Left Knee",
+                "Right Upper Leg",
+                "Left Upper Leg",
+                "Right Clavicle",
+                "Left Clavicle",
+                "Weapon Bone",
+                "Tail",
+                "Bip01",
+                "Root Bone",
+                "BoneOffset",
+                "AttachLight",
+                "Arrow",
+                "Camera",
+                "Collision",
+                "Right_Wrist",
+                "Left_Wrist",
+                "Shield_Bone",
+                "Right_Forearm",
+                "Left_Forearm",
+                "Right_Upper_Arm",
+                "Left_Clavicle",
+                "Weapon_Bone",
+                "Root_Bone",
+            };
+
+            std::vector<std::string> result;
+            result.reserve(std::size(names));
+
+            for (std::string_view name : names)
+            {
+                std::string prefixedName("Tri ");
+                prefixedName += name;
+                result.push_back(std::move(prefixedName));
+            }
+
+            std::sort(result.begin(), result.end(), Misc::StringUtils::ciLess);
+
+            return result;
+        }
     }
 
     osg::ref_ptr<osg::Node> load (const std::string& normalizedFilename, const VFS::Manager* vfs, Resource::ImageManager* imageManager, Resource::NifFileManager* nifFileManager)
@@ -638,23 +699,9 @@ namespace Resource
             if (name.empty())
                 return false;
 
-            static std::vector<std::string> reservedNames;
+            static const std::vector<std::string> reservedNames = makeSortedReservedNames();
-            if (reservedNames.empty())
-            {
-                const char* reserved[] = {"Head", "Neck", "Chest", "Groin", "Right Hand", "Left Hand", "Right Wrist", "Left Wrist", "Shield Bone", "Right Forearm", "Left Forearm", "Right Upper Arm",
-                                          "Left Upper Arm", "Right Foot", "Left Foot", "Right Ankle", "Left Ankle", "Right Knee", "Left Knee", "Right Upper Leg", "Left Upper Leg", "Right Clavicle",
-                                          "Left Clavicle", "Weapon Bone", "Tail", "Bip01", "Root Bone", "BoneOffset", "AttachLight", "Arrow", "Camera", "Collision", "Right_Wrist", "Left_Wrist",
-                                          "Shield_Bone", "Right_Forearm", "Left_Forearm", "Right_Upper_Arm", "Left_Clavicle", "Weapon_Bone", "Root_Bone"};
 
-                reservedNames = std::vector<std::string>(reserved, reserved + sizeof(reserved)/sizeof(reserved[0]));
+            const auto it = Misc::partialBinarySearch(reservedNames.begin(), reservedNames.end(), name);
-
-                for (unsigned int i=0; i<sizeof(reserved)/sizeof(reserved[0]); ++i)
-                    reservedNames.push_back(std::string("Tri ") + reserved[i]);
-
-                std::sort(reservedNames.begin(), reservedNames.end(), Misc::StringUtils::ciLess);
-            }
-
-            std::vector<std::string>::iterator it = Misc::partialBinarySearch(reservedNames.begin(), reservedNames.end(), name);
             return it != reservedNames.end();
         }