-# Add libusb in case of libdivecomputer compiled with usb support.
-LIBS = `pkg-config --libs gtk+-2.0 glib-2.0 gconf-2.0`
+# Libusb-1.0 is only required if libdivecomputer was built with it.
+# And libdivecomputer is only built with it if libusb-1.0 is
+# installed. So get libusb if it exists, but don't complain
+# about it if it doesn't.
+LIBUSB = $(shell pkg-config --libs libusb-1.0 2> /dev/null)
+
+LIBXML2 = $(shell xml2-config --libs)
+LIBGTK = $(shell pkg-config --libs gtk+-2.0 glib-2.0 gconf-2.0)
+LIBDIVECOMPUTER = $(LIBDIVECOMPUTERARCHIVE) $(LIBUSB)
+
+LIBS = $(LIBXML2) $(LIBGTK) $(LIBDIVECOMPUTER) -lpthread