diff -ruN -x CVS pkgsrc-2017Q2/graphics/glu/Makefile pkgsrc/graphics/glu/Makefile
--- pkgsrc-2017Q2/graphics/glu/Makefile	2015-04-25 16:23:11.000000000 +0200
+++ pkgsrc/graphics/glu/Makefile	2017-07-31 15:10:11.748824412 +0200
@@ -19,4 +19,5 @@
 PKGCONFIG_OVERRIDE+=	glu.pc.in
 
 .include "../../graphics/MesaLib/buildlink3.mk"
+.include "../../security/libgcrypt/buildlink3.mk"
 .include "../../mk/bsd.pkg.mk"