diff --git a/dlls/ddraw/tests/d3d.c b/dlls/ddraw/tests/d3d.c
index 0409dce2422..55dc77289f8 100644
--- a/dlls/ddraw/tests/d3d.c
+++ b/dlls/ddraw/tests/d3d.c
@@ -34,7 +34,7 @@ static LPDIRECT3DVERTEXBUFFER7 lpVBufDest2 = NULL;
 
 /* To compare bad floating point numbers. Not the ideal way to do it,
  * but it should be enough for here */
-#define comparefloat(a, b) ( ((a - b) < 0.0001) && ((a-b) > -0.0001) )
+#define comparefloat(a, b) ( (((a) - (b)) < 0.0001) && (((a) - (b)) > -0.0001) )
 
 static HRESULT (WINAPI *pDirectDrawCreateEx)(LPGUID,LPVOID*,REFIID,LPUNKNOWN);