diff --git a/DetourTileCache/Include/DetourTileCache.h b/DetourTileCache/Include/DetourTileCache.h
index 21ee25e..e2e3f42 100644
--- a/DetourTileCache/Include/DetourTileCache.h
+++ b/DetourTileCache/Include/DetourTileCache.h
@@ -63,6 +63,8 @@ struct dtTileCacheParams
 
 struct dtTileCacheMeshProcess
 {
+	virtual ~dtTileCacheMeshProcess() { }
+
 	virtual void process(struct dtNavMeshCreateParams* params,
 						 unsigned char* polyAreas, unsigned short* polyFlags) = 0;
 };
diff --git a/DetourTileCache/Include/DetourTileCacheBuilder.h b/DetourTileCache/Include/DetourTileCacheBuilder.h
index e2b7984..938d415 100644
--- a/DetourTileCache/Include/DetourTileCacheBuilder.h
+++ b/DetourTileCache/Include/DetourTileCacheBuilder.h
@@ -78,6 +78,8 @@ struct dtTileCachePolyMesh
 
 struct dtTileCacheAlloc
 {
+	virtual ~dtTileCacheAlloc() { }
+
 	virtual void reset()
 	{
 	}
@@ -95,6 +97,8 @@ struct dtTileCacheAlloc
 
 struct dtTileCacheCompressor
 {
+	virtual ~dtTileCacheCompressor() { }
+
 	virtual int maxCompressedSize(const int bufferSize) = 0;
 	virtual dtStatus compress(const unsigned char* buffer, const int bufferSize,
 							  unsigned char* compressed, const int maxCompressedSize, int* compressedSize) = 0;