diff --git a/astro/gpstk/Makefile b/astro/gpstk/Makefile
index 27980bcb1c35..5f3f39376462 100644
--- a/astro/gpstk/Makefile
+++ b/astro/gpstk/Makefile
@@ -12,7 +12,7 @@ COMMENT=	Toolkit for developing GPS applications
 LICENSE=	GPLv3 LGPL3
 LICENSE_COMB=	multi
 
-USES=		cmake
+USES=		cmake compiler:c++11-lang
 USE_LDCONFIG=	yes
 
 USE_GITHUB=	yes