Core/Game: Move singleton instances into compilation units

* Fixes issues when building shared libraries
  (prevents gcc and clang from providing several instance)

(cherry picked from commit 329225b40d110bed634f8cd0a1ab5c6dc7bbbdd1)

2 files changed, 7 insertions, 5 deletions

diff --git a/src/server/game/Pools/PoolMgr.cpp b/src/server/game/Pools/PoolMgr.cpp
index 12fb8a06b62..81d318fb1d9 100644
--- a/src/server/game/Pools/PoolMgr.cpp
+++ b/src/server/game/Pools/PoolMgr.cpp
@@ -570,6 +570,12 @@ void PoolMgr::Initialize()
     mCreatureSearchMap.clear();
 }
 
+PoolMgr* PoolMgr::instance()
+{
+    static PoolMgr instance;
+    return &instance;
+}
+
 void PoolMgr::LoadFromDB()
 {
     // Pool templates
diff --git a/src/server/game/Pools/PoolMgr.h b/src/server/game/Pools/PoolMgr.h
index 51e0bcb4cac..6c48a011b73 100644
--- a/src/server/game/Pools/PoolMgr.h
+++ b/src/server/game/Pools/PoolMgr.h
@@ -108,11 +108,7 @@ class PoolMgr
         ~PoolMgr() { };
 
     public:
-        static PoolMgr* instance()
-        {
-            static PoolMgr instance;
-            return &instance;
-        }
+        static PoolMgr* instance();
 
         void LoadFromDB();
         void LoadQuestPools();