diff --git a/srcpkgs/telepathy-qt5/template b/srcpkgs/telepathy-qt5/template
index 61322d6b92b..bce1d8e3743 100644
--- a/srcpkgs/telepathy-qt5/template
+++ b/srcpkgs/telepathy-qt5/template
@@ -18,6 +18,8 @@ homepage="http://telepathy.freedesktop.org/"
 distfiles="http://telepathy.freedesktop.org/releases/${pkgname//5/}/${pkgname//5/}-${version}.tar.gz"
 checksum=496eb4951ea9b181d7d68a2122a885474c4f73b519319496aa1b97d9b361a1f8
 
+CXXFLAGS="-D_DEFAULT_SOURCE"
+
 subpackages="telepathy-qt5-farstream telepathy-qt5-devel"
 
 telepathy-qt5-farstream_package() {