--- /dev/null
+# Copyright 1999-2019 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=7
+
+DESCRIPTION="Optimized BLAS library based on GotoBLAS2"
+HOMEPAGE="http://xianyi.github.com/OpenBLAS/"
+SRC_URI="https://github.com/xianyi/OpenBLAS/tarball/v${PV} -> ${P}.tar.gz"
+
+LICENSE="BSD"
+SLOT="0"
+KEYWORDS="~amd64 ~x86 ~amd64-linux ~x86-linux ~x64-macos ~x86-macos"
+IUSE="dynamic openmp pthread serial static-libs eselect-ldso"
+REQUIRED_USE="?? ( openmp pthread serial )"
+
+RDEPEND="
+eselect-ldso? ( >=app-eselect/eselect-blas-0.2
+ !app-eselect/eselect-cblas
+ >=app-eselect/eselect-lapack-0.2 )
+"
+DEPEND="virtual/pkgconfig"
+
+PATCHES=( "${FILESDIR}/shared-blas-lapack.patch" )
+
+openblas_flags() {
+ local flags=()
+ use dynamic && \
+ flags+=( DYNAMIC_ARCH=1 TARGET=GENERIC NUM_THREADS=64 NO_AFFINITY=1 )
+ if use openmp; then
+ flags+=( USE_THREAD=1 USE_OPENMP=1 )
+ elif use pthread; then
+ flags+=( USE_THREAD=1 USE_OPENMP=0 )
+ else
+ flags+=( USE_THREAD=0 ) # serial
+ fi
+ flags+=( DESTDIR="${D}" PREFIX="${EPREFIX}/usr" )
+ flags+=( OPENBLAS_INCLUDE_DIR='$(PREFIX)'/include/${PN} )
+ flags+=( OPENBLAS_LIBRARY_DIR='$(PREFIX)'/$(get_libdir) )
+ echo "${flags[@]}"
+}
+
+src_unpack () {
+ default
+ find "${WORKDIR}" -maxdepth 1 -type d -name \*OpenBLAS\* && \
+ mv "${WORKDIR}"/*OpenBLAS* "${S}" || die
+}
+
+src_compile () {
+ emake $(openblas_flags)
+ emake -Cinterface shared-blas-lapack $(openblas_flags)
+}
+
+src_install () {
+ emake install $(openblas_flags)
+
+ if use eselect-ldso; then
+ dodir /usr/$(get_libdir)/blas/openblas/
+ insinto /usr/$(get_libdir)/blas/openblas/
+ doins interface/libblas.so.3
+ dosym libblas.so.3 usr/$(get_libdir)/blas/openblas/libblas.so
+ doins interface/libcblas.so.3
+ dosym libcblas.so.3 usr/$(get_libdir)/blas/openblas/libcblas.so
+
+ dodir /usr/$(get_libdir)/lapack/openblas/
+ insinto /usr/$(get_libdir)/lapack/openblas/
+ doins interface/liblapack.so.3
+ dosym liblapack.so.3 usr/$(get_libdir)/lapack/openblas/liblapack.so
+ fi
+}
+
+pkg_postinst () {
+ use eselect-ldso || return
+ local libdir=$(get_libdir) me="openblas"
+
+ # check blas
+ eselect blas add ${libdir} "${EROOT}"/usr/${libdir}/blas/${me} ${me}
+ local current_blas=$(eselect blas show ${libdir} | cut -d' ' -f2)
+ if [[ ${current_blas} == "${me}" || -z ${current_blas} ]]; then
+ eselect blas set ${libdir} ${me}
+ elog "Current eselect: BLAS/CBLAS ($libdir) -> [${current_blas}]."
+ else
+ elog "Current eselect: BLAS/CBLAS ($libdir) -> [${current_blas}]."
+ elog "To use blas [${me}] implementation, you have to issue (as root):"
+ elog "\t eselect blas set ${libdir} ${me}"
+ fi
+
+ # check lapack
+ eselect lapack add ${libdir} "${EROOT}"/usr/${libdir}/lapack/${me} ${me}
+ local current_lapack=$(eselect lapack show ${libdir} | cut -d' ' -f2)
+ if [[ ${current_lapack} == "${me}" || -z ${current_lapack} ]]; then
+ eselect lapack set ${libdir} ${me}
+ elog "Current eselect: LAPACK ($libdir) -> [${current_lapack}]."
+ else
+ elog "Current eselect: LAPACK ($libdir) -> [${current_lapack}]."
+ elog "To use lapack [${me}] implementation, you have to issue (as root):"
+ elog "\t eselect lapack set ${libdir} ${me}"
+ fi
+}
+
+pkg_postrm () {
+ if use eselect-ldso; then
+ eselect blas validate
+ eselect lapack validate
+ fi
+}