diff --git a/compile-tests/cfg-2.rs b/compile-tests/cfg-2.rs
index a7a660f..e65d2cd 100644
--- a/compile-tests/cfg-2.rs
+++ b/compile-tests/cfg-2.rs
@@ -1,15 +1,26 @@
-#[cfg(windows)]
+#[cfg(any(windows, unix))]
 #[repr(C)]
 struct Foo {
-    x: f32,
+    x: i32,
+}
+
+#[cfg(windows)]
+#[repr(C)]
+struct Bar {
+    y: Foo,
 }
 
 #[cfg(unix)]
 #[repr(C)]
-struct Foo {
-    y: f32,
+struct Bar {
+    z: Foo,
+}
+
+#[repr(C)]
+struct Root {
+    w: Bar,
 }
 
 #[no_mangle]
-extern "C" fn root(a: Foo)
+extern "C" fn root(a: Root)
 { }
diff --git a/compile-tests/cfg-2.toml b/compile-tests/cfg-2.toml
index b0c2b41..f4ca752 100644
--- a/compile-tests/cfg-2.toml
+++ b/compile-tests/cfg-2.toml
@@ -1,3 +1,4 @@
 [defines]
-"unix" = "__FILE__"
-"windows" = "PLATFORM_WIN"
+"unix" = "DEFINED"
+"macos" = "NOT_DEFINED"
+"windows" = "NOT_DEFINED"
diff --git a/test.py b/test.py
index a0c1d38..dca32d6 100755
--- a/test.py
+++ b/test.py
@@ -32,7 +32,7 @@ def gcc(src):
     if gcc_bin == None:
         gcc_bin = 'gcc'
 
-    subprocess.check_output([gcc_bin, "-c", src, "-o", "compile-tests/tmp.o"])
+    subprocess.check_output([gcc_bin, "-D", "DEFINED", "-c", src, "-o", "compile-tests/tmp.o"])
     os.remove("compile-tests/tmp.o")
 
 def gxx(src):
@@ -40,7 +40,7 @@ def gxx(src):
     if gxx_bin == None:
         gxx_bin = 'g++'
 
-    subprocess.check_output([gxx_bin, "-std=c++11", "-c", src, "-o", "compile-tests/tmp.o"])
+    subprocess.check_output([gxx_bin, "-D", "DEFINED", "-std=c++11", "-c", src, "-o", "compile-tests/tmp.o"])
     os.remove("compile-tests/tmp.o")
 
 def run_compile_test(rust_src, leave_output, c):