diff --git a/book_src/loading_opengl/win32.md b/book_src/loading_opengl/win32.md
index 4e7d8a7..4b7f208 100644
--- a/book_src/loading_opengl/win32.md
+++ b/book_src/loading_opengl/win32.md
@@ -590,7 +590,7 @@ pub const WS_CLIPCHILDREN: u32 = 0x02000000;
 /// neighboring child window.
 pub const WS_CLIPSIBLINGS: u32 = 0x04000000;
 
-pub unsafe fn create_app_window(
+pub unsafe fn create_app_window() {
   // ...
   let hwnd = CreateWindowExW(
     WS_EX_APPWINDOW | WS_EX_OVERLAPPEDWINDOW,