dev-ml/labltk: fix build with ocaml-4.12

Package-Manager: Portage-3.0.20, Repoman-3.0.3
Signed-off-by: Alfredo Tupone <tupone@gentoo.org>

dev-ml/labltk/labltk-8.06.10.ebuild

@@ -22,9 +22,14 @@ DEPEND="${RDEPEND}
 
 PATCHES=(
 	"${FILESDIR}/findlib.patch"
-	"${FILESDIR}"/${P}-this-expression-has-type.patch
 )
 
+src_prepare() {
+	has_version "dev-lang/ocaml:0/4.11" && \
+		eapply "${FILESDIR}"/${P}-this-expression-has-type.patch
+	default
+}
+
 src_configure() {
 	./configure --use-findlib --verbose $(usex X "--tk-x11" "--tk-no-x11") || die "configure failed!"
 }