--- a/gui/ui/Makefile.am
+++ b/gui/ui/Makefile.am
@@ -2,7 +2,7 @@
 
 if have_qt
 
-AM_CPPFLAGS = @QT_INCLUDES@
+AM_CPPFLAGS = @QT_CFLAGS@
 
 AM_CXXFLAGS = @OP_CXXFLAGS@