diff --git a/dlls/d3dx9_36/tests/effect.c b/dlls/d3dx9_36/tests/effect.c
index 44f931cdb28..482f0645c3d 100644
--- a/dlls/d3dx9_36/tests/effect.c
+++ b/dlls/d3dx9_36/tests/effect.c
@@ -1683,9 +1683,9 @@ static void test_effect_parameter_value(IDirect3DDevice9 *device)
             UINT res_value_offset = res[k].value_offset;
             D3DXHANDLE parameter;
             D3DXPARAMETER_DESC pdesc;
-            BOOL bvalue;
-            INT ivalue;
-            FLOAT fvalue;
+            BOOL bvalue = TRUE;
+            INT ivalue = 42;
+            FLOAT fvalue = 2.71828f;
             DWORD input_value[EFFECT_PARAMETER_VALUE_ARRAY_SIZE];
             DWORD expected_value[EFFECT_PARAMETER_VALUE_ARRAY_SIZE];
             UINT l, n, m, element;