ocaml-zarith: skip tests when bytecode only.

srcpkgs/ocaml-zarith/template

@@ -3,7 +3,6 @@ pkgname=ocaml-zarith
 version=1.13
 revision=1
 build_style=configure
-make_check_target="tests"
 hostmakedepends="perl"
 makedepends="gmp-devel ocaml"
 depends="gmp-devel"
@@ -25,3 +24,7 @@ pre_install() {
 post_install() {
 	vcopy META usr/lib/ocaml/zarith
 }
+do_check() {
+	command -v ocamlc.opt >/dev/null || return 0
+	make tests
+}