diff --git a/src/gui/configure.cmake b/src/gui/configure.cmake
index 0bf250ea..2d1bb645 100644
--- a/src/gui/configure.cmake
+++ b/src/gui/configure.cmake
@@ -174,9 +174,9 @@ qt_config_compile_test(egl_x11
 int main(void)
 {
     /* BEGIN TEST: */
-Display *dpy = EGL_DEFAULT_DISPLAY;
+Display *dpy = reinterpret_cast<Display *>(EGL_DEFAULT_DISPLAY);
 EGLNativeDisplayType egldpy = XOpenDisplay(\"\");
-dpy = egldpy;
+dpy = reinterpret_cast<Display *>(egldpy);
 EGLNativeWindowType w = XCreateWindow(dpy, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
 XDestroyWindow(dpy, w);
 XCloseDisplay(dpy);