check for the sync extension

diff --git a/configure.ac b/configure.ac
index 65304f5801b4a8559f86788b873352cd2c0d2d21..dc893b748097f8594781acd46c8d1888bb4a8e93 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -144,6 +144,7 @@ X11_EXT_XKB
 X11_EXT_XRANDR
 X11_EXT_SHAPE
 X11_EXT_XINERAMA
+X11_EXT_SYNC
 
 AC_CONFIG_FILES([
   Makefile