PR observation about another race condition

Signed-off-by: Esteban Papp <81431996+amznestebanpapp@users.noreply.github.com>

Code/Framework/AzCore/AzCore/Name/Internal/NameData.cpp

@@ -36,10 +36,13 @@ namespace AZ
 
         void NameData::release()
         {
+            // this could be released after we decrement the counter, therefore we will
+            // base the release on the hash which is stable
+            Hash hash = m_hash;
             AZ_Assert(m_useCount > 0, "m_useCount is already 0!");
             if (m_useCount.fetch_sub(1) == 1)
             {
-                AZ::NameDictionary::Instance().TryReleaseName(this);
+                AZ::NameDictionary::Instance().TryReleaseName(hash);
             }
         }
     }

Code/Framework/AzCore/AzCore/Name/NameDictionary.cpp

@@ -166,7 +166,7 @@ namespace AZ
         }
     }
 
-    void NameDictionary::TryReleaseName(Internal::NameData* nameData)
+    void NameDictionary::TryReleaseName(Name::Hash hash)
     {
         // Note that we don't remove NameData from the dictionary if it has been involved in a collision.
         // This avoids specific edge cases where a Name object could get an incorrect hash value. Consider
@@ -179,14 +179,6 @@ namespace AZ
         //      the dictionary *again*, this time with hash value 1000. Name objects pointing to the original
         //      entry and Name objects pointing to the new entry will fail comparison operations.
 
-        // Early exit to avoid locking the mutex unnecessarily.
-        if (nameData->m_hashCollision)
-        {
-            return;
-        }
-
-        // Get the hash before locking since another thread could be deleting the object within the lock
-        Internal::NameData::Hash hash = nameData->GetHash();
 
         AZStd::unique_lock<AZStd::shared_mutex> lock(m_sharedMutex);
 
@@ -202,7 +194,7 @@ namespace AZ
             return;
         }
 
-        nameData = dictIt->second; // restore the pointer in case the intrusive ptr was already assigned by other thread
+        Internal::NameData* nameData = dictIt->second; // restore the pointer in case the intrusive ptr was already assigned by other thread
 
         // Check m_hashCollision again inside the m_sharedMutex because a new collision could have happened
         // on another thread before taking the lock.

Code/Framework/AzCore/AzCore/Name/NameDictionary.h

@@ -83,7 +83,7 @@ namespace AZ
 
         // Attempts to release the name from the dictionary, but checks to make sure
         // a reference wasn't taken by another thread.
-        void TryReleaseName(Internal::NameData* data);
+        void TryReleaseName(Name::Hash hash);
         
         //////////////////////////////////////////////////////////////////////////