diff --git a/stepmania/autoconf/m4/opengl.m4 b/stepmania/autoconf/m4/opengl.m4
index 169978c72f..e213addf18 100644
--- a/stepmania/autoconf/m4/opengl.m4
+++ b/stepmania/autoconf/m4/opengl.m4
@@ -46,7 +46,7 @@ AC_DEFUN([SM_X_WITH_OPENGL],
 	if test "$have_xrandr" = "no"; then
 		echo "*** Direct X11 support needs Xrandr libraries and headers."
 		echo "*** Couldn't find needed headers. Continuing without X11 backend."
-		no_x = yes
+		no_x=yes
 	else
 		XLIBS="$XLIBS -lXrandr"
 	fi