sci-biology/allpathslg: Unconditionally require OpenMP support

Gentoo-bug: 591166
* The configure script of sci-biology/allpathslg allows for
  specifying --enable/--disable-openmp, without it actually
  being optional.

Package-Manager: portage-2.3.0

sci-biology/allpathslg/allpathslg-52488-r2.ebuild

@@ -4,7 +4,7 @@
 
 EAPI=6
 
-inherit autotools flag-o-matic
+inherit autotools flag-o-matic toolchain-funcs
 
 DESCRIPTION="De novo assembly of whole-genome shotgun microreads"
 # see also http://www.broadinstitute.org/software/allpaths-lg/blog/?page_id=12
@@ -14,14 +14,13 @@ SRC_URI="ftp://ftp.broadinstitute.org/pub/crd/ALLPATHS/Release-LG/latest_source_
 LICENSE="MIT"
 SLOT="0"
 KEYWORDS="~amd64"
-IUSE="openmp"
 
 RDEPEND="
 	!sci-biology/allpaths
 	!sci-biology/vaal"
 DEPEND="
 	${RDEPEND}
-	dev-libs/boost"
+	dev-libs/boost:="
 
 PATCHES=(
 	"${FILESDIR}/${P}_fix-buildsystem.patch"
@@ -33,8 +32,21 @@ pkg_pretend() {
 	# seems pre gcc-4.7 users must stay with:
 	# ftp://ftp.broadinstitute.org/pub/crd/ALLPATHS/Release-LG/latest_source_code/2013/2013-01/allpathslg-44837.tar.gz
 	if [[ ${MERGE_TYPE} != binary ]]; then
-		[[ $(tc-getCC) == *gcc* ]] && [[ $(gcc-version) < 4.7 ]] && \
-		die "You need to use gcc >4.7"
+		tc-is-gcc && [[ $(gcc-version) < 4.7 ]] && \
+			die "You need to use gcc >4.7"
+	fi
+}
+
+pkg_setup() {
+	if ! tc-has-openmp; then
+		ewarn "OpenMP is not available in your current selected compiler"
+
+		if tc-is-clang; then
+			ewarn "OpenMP support in sys-devel/clang is provided by sys-libs/libomp,"
+			ewarn "which you will need to build ${CATEGORY}/${PN} with USE=\"openmp\""
+		fi
+
+		die "need openmp capable compiler"
 	fi
 }
 
@@ -43,8 +55,3 @@ src_prepare() {
 
 	eautoreconf
 }
-
-src_configure() {
-	econf \
-		$(use_enable openmp)
-}