diff --git a/dlls/user32/tests/cursoricon.c b/dlls/user32/tests/cursoricon.c
index 5f2306aee4f..4b79d4674bd 100644
--- a/dlls/user32/tests/cursoricon.c
+++ b/dlls/user32/tests/cursoricon.c
@@ -83,6 +83,7 @@ typedef struct {
 
 typedef struct {
     BYTE data[32*32*4];
+    BYTE mask_data[32*32/8];
 } ani_data32x32x32;
 
 typedef struct {