diff --git a/src/core.c b/src/core.c
index ce2fbf34e..363499ff9 100644
--- a/src/core.c
+++ b/src/core.c
@@ -61,10 +61,12 @@ void b2SetAssertFcn( b2AssertFcn* assertFcn )
 	b2AssertHandler = assertFcn;
 }
 
+#if !defined( NDEBUG ) || defined( B2_ENABLE_ASSERT )
 int b2InternalAssertFcn( const char* condition, const char* fileName, int lineNumber )
 {
 	return b2AssertHandler( condition, fileName, lineNumber );
 }
+#endif
 
 b2Version b2GetVersion( void )
 {
diff --git a/src/dynamic_tree.c b/src/dynamic_tree.c
index 3ab24978d..7d797f8a5 100644
--- a/src/dynamic_tree.c
+++ b/src/dynamic_tree.c
@@ -986,7 +986,7 @@ void b2DynamicTree_Validate( const b2DynamicTree* tree )
 	}
 
 	int height = b2DynamicTree_GetHeight( tree );
-	int computedHeight = b2ComputeHeight( tree );
+	int computedHeight = b2ComputeHeight( tree, tree->root );
 	B2_ASSERT( height == computedHeight );
 
 	B2_ASSERT( tree->nodeCount + freeCount == tree->nodeCapacity );