6 files changed, 830 insertions, 0 deletions
diff --git a/sys-libs/compiler-rt-sanitizers/compiler-rt-sanitizers-11.0.0.9999.ebuild b/sys-libs/compiler-rt-sanitizers/compiler-rt-sanitizers-11.0.0.9999.ebuild
new file mode 100644
index 000000000000..72ee582f5c26
--- /dev/null
+++ b/sys-libs/compiler-rt-sanitizers/compiler-rt-sanitizers-11.0.0.9999.ebuild
@@ -0,0 +1,158 @@
+# Copyright 1999-2020 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=7
+
+PYTHON_COMPAT=( python{2_7,3_{6,7}} )
+inherit check-reqs cmake-utils flag-o-matic llvm llvm.org \
+	multiprocessing python-any-r1
+
+DESCRIPTION="Compiler runtime libraries for clang (sanitizers & xray)"
+HOMEPAGE="https://llvm.org/"
+LLVM_COMPONENTS=( compiler-rt )
+LLVM_TEST_COMPONENTS=( llvm/lib/Testing/Support llvm/utils/unittest )
+llvm.org_set_globals
+
+LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
+SLOT="$(ver_cut 1-3)"
+KEYWORDS=""
+IUSE="+clang +libfuzzer +profile +sanitize test +xray elibc_glibc"
+# FIXME: libfuzzer does not enable all its necessary dependencies
+REQUIRED_USE="libfuzzer? ( || ( sanitize xray ) )"
+RESTRICT="!test? ( test ) !clang? ( test )"
+
+CLANG_SLOT=${SLOT%%.*}
+# llvm-6 for new lit options
+DEPEND="
+	>=sys-devel/llvm-6"
+BDEPEND="
+	clang? ( sys-devel/clang )
+	elibc_glibc? ( net-libs/libtirpc )
+	test? (
+		!<sys-apps/sandbox-2.13
+		$(python_gen_any_dep ">=dev-python/lit-5[\${PYTHON_USEDEP}]")
+		=sys-devel/clang-${PV%_*}*:${CLANG_SLOT}
+		sys-libs/compiler-rt:${SLOT} )
+	${PYTHON_DEPS}"
+
+# least intrusive of all
+CMAKE_BUILD_TYPE=RelWithDebInfo
+
+python_check_deps() {
+	use test || return 0
+	has_version "dev-python/lit[${PYTHON_USEDEP}]"
+}
+
+check_space() {
+	if use test; then
+		local CHECKREQS_DISK_BUILD=11G
+		check-reqs_pkg_pretend
+	fi
+}
+
+pkg_pretend() {
+	check_space
+}
+
+pkg_setup() {
+	check_space
+	llvm_pkg_setup
+	python-any-r1_pkg_setup
+}
+
+src_prepare() {
+	cmake-utils_src_prepare
+
+	if use test; then
+		# remove tests that are (still) broken by new glibc
+		# https://bugs.llvm.org/show_bug.cgi?id=36065
+		if use elibc_glibc && has_version '>=sys-libs/glibc-2.25'; then
+			rm test/lsan/TestCases/Linux/fork_and_leak.cpp || die
+		fi
+	fi
+}
+
+src_configure() {
+	# pre-set since we need to pass it to cmake
+	BUILD_DIR=${WORKDIR}/compiler-rt_build
+
+	if use clang; then
+		local -x CC=${CHOST}-clang
+		local -x CXX=${CHOST}-clang++
+		strip-unsupported-flags
+	fi
+
+	local mycmakeargs=(
+		-DCOMPILER_RT_INSTALL_PATH="${EPREFIX}/usr/lib/clang/${SLOT}"
+		# use a build dir structure consistent with install
+		# this makes it possible to easily deploy test-friendly clang
+		-DCOMPILER_RT_OUTPUT_DIR="${BUILD_DIR}/lib/clang/${SLOT}"
+
+		-DCOMPILER_RT_INCLUDE_TESTS=$(usex test)
+		# builtins & crt installed by sys-libs/compiler-rt
+		-DCOMPILER_RT_BUILD_BUILTINS=OFF
+		-DCOMPILER_RT_BUILD_CRT=OFF
+		-DCOMPILER_RT_BUILD_LIBFUZZER=$(usex libfuzzer)
+		-DCOMPILER_RT_BUILD_PROFILE=$(usex profile)
+		-DCOMPILER_RT_BUILD_SANITIZERS=$(usex sanitize)
+		-DCOMPILER_RT_BUILD_XRAY=$(usex xray)
+	)
+	if use test; then
+		mycmakeargs+=(
+			-DLLVM_MAIN_SRC_DIR="${WORKDIR}/llvm"
+			-DLLVM_EXTERNAL_LIT="${EPREFIX}/usr/bin/lit"
+			-DLLVM_LIT_ARGS="-vv;-j;${LIT_JOBS:-$(makeopts_jobs "${MAKEOPTS}" "$(get_nproc)")}"
+
+			# they are created during src_test()
+			-DCOMPILER_RT_TEST_COMPILER="${BUILD_DIR}/lib/llvm/${CLANG_SLOT}/bin/clang"
+			-DCOMPILER_RT_TEST_CXX_COMPILER="${BUILD_DIR}/lib/llvm/${CLANG_SLOT}/bin/clang++"
+		)
+
+		# same flags are passed for build & tests, so we need to strip
+		# them down to a subset supported by clang
+		CC=${EPREFIX}/usr/lib/llvm/${CLANG_SLOT}/bin/clang \
+		CXX=${EPREFIX}/usr/lib/llvm/${CLANG_SLOT}/bin/clang++ \
+		strip-unsupported-flags
+	fi
+
+	if use prefix && [[ "${CHOST}" == *-darwin* ]] ; then
+		mycmakeargs+=(
+			# disable use of SDK for the system itself
+			-DDARWIN_macosx_CACHED_SYSROOT=/
+		)
+	fi
+
+	cmake-utils_src_configure
+
+	if use test; then
+		local sys_dir=( "${EPREFIX}"/usr/lib/clang/${SLOT}/lib/* )
+		[[ -e ${sys_dir} ]] || die "Unable to find ${sys_dir}"
+		[[ ${#sys_dir[@]} -eq 1 ]] || die "Non-deterministic compiler-rt install: ${sys_dir[*]}"
+
+		# copy clang over since resource_dir is located relatively to binary
+		# therefore, we can put our new libraries in it
+		mkdir -p "${BUILD_DIR}"/lib/{llvm/${CLANG_SLOT}/{bin,$(get_libdir)},clang/${SLOT}/include} || die
+		cp "${EPREFIX}"/usr/lib/llvm/${CLANG_SLOT}/bin/clang{,++} \
+			"${BUILD_DIR}"/lib/llvm/${CLANG_SLOT}/bin/ || die
+		cp "${EPREFIX}"/usr/lib/clang/${SLOT}/include/*.h \
+			"${BUILD_DIR}"/lib/clang/${SLOT}/include/ || die
+		cp "${sys_dir}"/*builtins*.a \
+			"${BUILD_DIR}/lib/clang/${SLOT}/lib/${sys_dir##*/}/" || die
+		# we also need LLVMgold.so for gold-based tests
+		if [[ -f ${EPREFIX}/usr/lib/llvm/${CLANG_SLOT}/$(get_libdir)/LLVMgold.so ]]; then
+			ln -s "${EPREFIX}"/usr/lib/llvm/${CLANG_SLOT}/$(get_libdir)/LLVMgold.so \
+				"${BUILD_DIR}"/lib/llvm/${CLANG_SLOT}/$(get_libdir)/ || die
+		fi
+	fi
+}
+
+src_test() {
+	# respect TMPDIR!
+	local -x LIT_PRESERVES_TMP=1
+	# disable sandbox to have it stop clobbering LD_PRELOAD
+	local -x SANDBOX_ON=0
+	# wipe LD_PRELOAD to make ASAN happy
+	local -x LD_PRELOAD=
+
+	cmake-utils_src_make check-all
+}
diff --git a/sys-libs/compiler-rt/compiler-rt-11.0.0.9999.ebuild b/sys-libs/compiler-rt/compiler-rt-11.0.0.9999.ebuild
new file mode 100644
index 000000000000..7a7778ae76b9
--- /dev/null
+++ b/sys-libs/compiler-rt/compiler-rt-11.0.0.9999.ebuild
@@ -0,0 +1,110 @@
+# Copyright 1999-2020 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=7
+
+PYTHON_COMPAT=( python{2_7,3_{6,7}} )
+inherit cmake-utils flag-o-matic llvm llvm.org multiprocessing \
+	python-any-r1 toolchain-funcs
+
+DESCRIPTION="Compiler runtime library for clang (built-in part)"
+HOMEPAGE="https://llvm.org/"
+LLVM_COMPONENTS=( compiler-rt )
+llvm.org_set_globals
+
+LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
+SLOT="$(ver_cut 1-3)"
+KEYWORDS=""
+IUSE="+clang test"
+RESTRICT="!test? ( test ) !clang? ( test )"
+
+CLANG_SLOT=${SLOT%%.*}
+# llvm-6 for new lit options
+DEPEND="
+	>=sys-devel/llvm-6"
+BDEPEND="
+	clang? ( sys-devel/clang )
+	test? (
+		$(python_gen_any_dep "dev-python/lit[\${PYTHON_USEDEP}]")
+		=sys-devel/clang-${PV%_*}*:${CLANG_SLOT} )
+	${PYTHON_DEPS}"
+
+# least intrusive of all
+CMAKE_BUILD_TYPE=RelWithDebInfo
+
+python_check_deps() {
+	use test || return 0
+	has_version "dev-python/lit[${PYTHON_USEDEP}]"
+}
+
+pkg_pretend() {
+	if ! use clang && ! tc-is-clang; then
+		ewarn "Building using a compiler other than clang may result in broken atomics"
+		ewarn "library. Enable USE=clang unless you have a very good reason not to."
+	fi
+}
+
+pkg_setup() {
+	llvm_pkg_setup
+	python-any-r1_pkg_setup
+}
+
+test_compiler() {
+	$(tc-getCC) ${CFLAGS} ${LDFLAGS} "${@}" -o /dev/null -x c - \
+		<<<'int main() { return 0; }' &>/dev/null
+}
+
+src_configure() {
+	# pre-set since we need to pass it to cmake
+	BUILD_DIR=${WORKDIR}/${P}_build
+
+	local nolib_flags=( -nodefaultlibs -lc )
+	if use clang; then
+		local -x CC=${CHOST}-clang
+		local -x CXX=${CHOST}-clang++
+		# ensure we can use clang before installing compiler-rt
+		local -x LDFLAGS="${LDFLAGS} ${nolib_flags[*]}"
+		strip-unsupported-flags
+	elif ! test_compiler; then
+		if test_compiler "${nolib_flags[@]}"; then
+			local -x LDFLAGS="${LDFLAGS} ${nolib_flags[*]}"
+			ewarn "${CC} seems to lack runtime, trying with ${nolib_flags[*]}"
+		fi
+	fi
+
+	local mycmakeargs=(
+		-DCOMPILER_RT_INSTALL_PATH="${EPREFIX}/usr/lib/clang/${SLOT}"
+
+		-DCOMPILER_RT_INCLUDE_TESTS=$(usex test)
+		-DCOMPILER_RT_BUILD_LIBFUZZER=OFF
+		-DCOMPILER_RT_BUILD_PROFILE=OFF
+		-DCOMPILER_RT_BUILD_SANITIZERS=OFF
+		-DCOMPILER_RT_BUILD_XRAY=OFF
+	)
+
+	if use prefix && [[ "${CHOST}" == *-darwin* ]] ; then
+		mycmakeargs+=(
+			# disable use of SDK for the system itself
+			-DDARWIN_macosx_CACHED_SYSROOT=/
+		)
+	fi
+
+	if use test; then
+		mycmakeargs+=(
+			-DLLVM_EXTERNAL_LIT="${EPREFIX}/usr/bin/lit"
+			-DLLVM_LIT_ARGS="-vv;-j;${LIT_JOBS:-$(makeopts_jobs "${MAKEOPTS}" "$(get_nproc)")}"
+
+			-DCOMPILER_RT_TEST_COMPILER="${EPREFIX}/usr/lib/llvm/${CLANG_SLOT}/bin/clang"
+			-DCOMPILER_RT_TEST_CXX_COMPILER="${EPREFIX}/usr/lib/llvm/${CLANG_SLOT}/bin/clang++"
+		)
+	fi
+
+	cmake-utils_src_configure
+}
+
+src_test() {
+	# respect TMPDIR!
+	local -x LIT_PRESERVES_TMP=1
+
+	cmake-utils_src_make check-builtins
+}
diff --git a/sys-libs/libcxx/libcxx-11.0.0.9999.ebuild b/sys-libs/libcxx/libcxx-11.0.0.9999.ebuild
new file mode 100644
index 000000000000..45df844722bb
--- /dev/null
+++ b/sys-libs/libcxx/libcxx-11.0.0.9999.ebuild
@@ -0,0 +1,211 @@
+# Copyright 1999-2020 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=7
+
+PYTHON_COMPAT=( python{2_7,3_{6,7}} )
+inherit cmake-multilib llvm llvm.org multiprocessing python-any-r1 \
+	toolchain-funcs
+
+DESCRIPTION="New implementation of the C++ standard library, targeting C++11"
+HOMEPAGE="https://libcxx.llvm.org/"
+LLVM_COMPONENTS=( libcxx )
+llvm.org_set_globals
+
+LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
+SLOT="0"
+KEYWORDS=""
+IUSE="elibc_glibc elibc_musl +libcxxabi libcxxrt +libunwind +static-libs test"
+REQUIRED_USE="libunwind? ( || ( libcxxabi libcxxrt ) )
+	?? ( libcxxabi libcxxrt )"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+	libcxxabi? ( ~sys-libs/libcxxabi-${PV}[libunwind=,static-libs?,${MULTILIB_USEDEP}] )
+	libcxxrt? ( sys-libs/libcxxrt[libunwind=,static-libs?,${MULTILIB_USEDEP}] )
+	!libcxxabi? ( !libcxxrt? ( >=sys-devel/gcc-4.7:=[cxx] ) )"
+# llvm-6 for new lit options
+# clang-3.9.0 installs necessary target symlinks unconditionally
+# which removes the need for MULTILIB_USEDEP
+DEPEND="${RDEPEND}
+	>=sys-devel/llvm-6"
+BDEPEND="
+	test? ( >=sys-devel/clang-3.9.0
+		$(python_gen_any_dep 'dev-python/lit[${PYTHON_USEDEP}]') )"
+
+DOCS=( CREDITS.TXT )
+
+PATCHES=(
+	# Add link flag "-Wl,-z,defs" to avoid underlinking; this is needed in a
+	# out-of-tree build.
+	"${FILESDIR}/${PN}-3.9-cmake-link-flags.patch"
+)
+
+# least intrusive of all
+CMAKE_BUILD_TYPE=RelWithDebInfo
+
+python_check_deps() {
+	has_version "dev-python/lit[${PYTHON_USEDEP}]"
+}
+
+pkg_setup() {
+	llvm_pkg_setup
+	use test && python-any-r1_pkg_setup
+
+	if ! use libcxxabi && ! use libcxxrt && ! tc-is-gcc ; then
+		eerror "To build ${PN} against libsupc++, you have to use gcc. Other"
+		eerror "compilers are not supported. Please set CC=gcc and CXX=g++"
+		eerror "and try again."
+		die
+	fi
+	if tc-is-gcc && [[ $(gcc-version) < 4.7 ]] ; then
+		eerror "${PN} needs to be built with gcc-4.7 or later (or other"
+		eerror "conformant compilers). Please use gcc-config to switch to"
+		eerror "gcc-4.7 or later version."
+		die
+	fi
+}
+
+test_compiler() {
+	$(tc-getCXX) ${CXXFLAGS} ${LDFLAGS} "${@}" -o /dev/null -x c++ - \
+		<<<'int main() { return 0; }' &>/dev/null
+}
+
+src_configure() {
+	# note: we need to do this before multilib kicks in since it will
+	# alter the CHOST
+	local cxxabi cxxabi_incs
+	if use libcxxabi; then
+		cxxabi=libcxxabi
+		cxxabi_incs="${EPREFIX}/usr/include/libcxxabi"
+	elif use libcxxrt; then
+		cxxabi=libcxxrt
+		cxxabi_incs="${EPREFIX}/usr/include/libcxxrt"
+	else
+		local gcc_inc="${EPREFIX}/usr/lib/gcc/${CHOST}/$(gcc-fullversion)/include/g++-v$(gcc-major-version)"
+		cxxabi=libsupc++
+		cxxabi_incs="${gcc_inc};${gcc_inc}/${CHOST}"
+	fi
+
+	multilib-minimal_src_configure
+}
+
+multilib_src_configure() {
+	# we want -lgcc_s for unwinder, and for compiler runtime when using
+	# gcc, clang with gcc runtime (or any unknown compiler)
+	local extra_libs=() want_gcc_s=ON want_compiler_rt=OFF
+	if use libunwind; then
+		# work-around missing -lunwind upstream
+		extra_libs+=( -lunwind )
+		# if we're using libunwind and clang with compiler-rt, we want
+		# to link to compiler-rt instead of -lgcc_s
+		if tc-is-clang; then
+			local compiler_rt=$($(tc-getCC) ${CFLAGS} ${CPPFLAGS} \
+			   ${LDFLAGS} -print-libgcc-file-name)
+			if [[ ${compiler_rt} == *libclang_rt* ]]; then
+				want_gcc_s=OFF
+				want_compiler_rt=ON
+				extra_libs+=( "${compiler_rt}" )
+			fi
+		fi
+	fi
+
+	# bootstrap: cmake is unhappy if compiler can't link to stdlib
+	local nolib_flags=( -nodefaultlibs -lc )
+	if ! test_compiler; then
+		if test_compiler "${nolib_flags[@]}"; then
+			local -x LDFLAGS="${LDFLAGS} ${nolib_flags[*]}"
+			ewarn "${CXX} seems to lack runtime, trying with ${nolib_flags[*]}"
+		fi
+	fi
+
+	local libdir=$(get_libdir)
+	local mycmakeargs=(
+		-DLIBCXX_LIBDIR_SUFFIX=${libdir#lib}
+		-DLIBCXX_ENABLE_SHARED=ON
+		-DLIBCXX_ENABLE_STATIC=$(usex static-libs)
+		-DLIBCXX_CXX_ABI=${cxxabi}
+		-DLIBCXX_CXX_ABI_INCLUDE_PATHS=${cxxabi_incs}
+		# we're using our own mechanism for generating linker scripts
+		-DLIBCXX_ENABLE_ABI_LINKER_SCRIPT=OFF
+		-DLIBCXX_HAS_MUSL_LIBC=$(usex elibc_musl)
+		-DLIBCXX_HAS_GCC_S_LIB=${want_gcc_s}
+		-DLIBCXX_INCLUDE_TESTS=$(usex test)
+		-DLIBCXX_USE_COMPILER_RT=${want_compiler_rt}
+		-DCMAKE_SHARED_LINKER_FLAGS="${extra_libs[*]} ${LDFLAGS}"
+	)
+
+	if use test; then
+		local clang_path=$(type -P "${CHOST:+${CHOST}-}clang" 2>/dev/null)
+		local jobs=${LIT_JOBS:-$(makeopts_jobs "${MAKEOPTS}" "$(get_nproc)")}
+
+		[[ -n ${clang_path} ]] || die "Unable to find ${CHOST}-clang for tests"
+
+		mycmakeargs+=(
+			-DLLVM_EXTERNAL_LIT="${EPREFIX}/usr/bin/lit"
+			-DLLVM_LIT_ARGS="-vv;-j;${jobs};--param=cxx_under_test=${clang_path}"
+		)
+	fi
+	cmake-utils_src_configure
+}
+
+multilib_src_test() {
+	local -x LIT_PRESERVES_TMP=1
+	cmake-utils_src_make check-libcxx
+}
+
+# Usage: deps
+gen_ldscript() {
+	local output_format
+	output_format=$($(tc-getCC) ${CFLAGS} ${LDFLAGS} -Wl,--verbose 2>&1 | sed -n 's/^OUTPUT_FORMAT("\([^"]*\)",.*/\1/p')
+	[[ -n ${output_format} ]] && output_format="OUTPUT_FORMAT ( ${output_format} )"
+
+	cat <<-END_LDSCRIPT
+/* GNU ld script
+   Include missing dependencies
+*/
+${output_format}
+GROUP ( $@ )
+END_LDSCRIPT
+}
+
+gen_static_ldscript() {
+	local libdir=$(get_libdir)
+	local cxxabi_lib=$(usex libcxxabi "libc++abi.a" "$(usex libcxxrt "libcxxrt.a" "libsupc++.a")")
+
+	# Move it first.
+	mv "${ED}/usr/${libdir}/libc++.a" "${ED}/usr/${libdir}/libc++_static.a" || die
+	# Generate libc++.a ldscript for inclusion of its dependencies so that
+	# clang++ -stdlib=libc++ -static works out of the box.
+	local deps="libc++_static.a ${cxxabi_lib} $(usex libunwind libunwind.a libgcc_eh.a)"
+	# On Linux/glibc it does not link without libpthread or libdl. It is
+	# fine on FreeBSD.
+	use elibc_glibc && deps+=" libpthread.a libdl.a"
+
+	gen_ldscript "${deps}" > "${ED}/usr/${libdir}/libc++.a" || die
+}
+
+gen_shared_ldscript() {
+	local libdir=$(get_libdir)
+	# libsupc++ doesn't have a shared version
+	local cxxabi_lib=$(usex libcxxabi "libc++abi.so" "$(usex libcxxrt "libcxxrt.so" "libsupc++.a")")
+
+	mv "${ED}/usr/${libdir}/libc++.so" "${ED}/usr/${libdir}/libc++_shared.so" || die
+	local deps="libc++_shared.so ${cxxabi_lib} $(usex libunwind libunwind.so libgcc_s.so)"
+
+	gen_ldscript "${deps}" > "${ED}/usr/${libdir}/libc++.so" || die
+}
+
+multilib_src_install() {
+	cmake-utils_src_install
+	gen_shared_ldscript
+	use static-libs && gen_static_ldscript
+}
+
+pkg_postinst() {
+	elog "This package (${PN}) is mainly intended as a replacement for the C++"
+	elog "standard library when using clang."
+	elog "To use it, instead of libstdc++, use:"
+	elog "    clang++ -stdlib=libc++"
+	elog "to compile your C++ programs."
+}
diff --git a/sys-libs/libcxxabi/libcxxabi-11.0.0.9999.ebuild b/sys-libs/libcxxabi/libcxxabi-11.0.0.9999.ebuild
new file mode 100644
index 000000000000..d096ef109678
--- /dev/null
+++ b/sys-libs/libcxxabi/libcxxabi-11.0.0.9999.ebuild
@@ -0,0 +1,119 @@
+# Copyright 1999-2020 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=7
+
+PYTHON_COMPAT=( python{2_7,3_{6,7}} )
+inherit cmake-multilib llvm llvm.org multiprocessing python-any-r1
+
+DESCRIPTION="Low level support for a standard C++ library"
+HOMEPAGE="https://libcxxabi.llvm.org/"
+# libcxx is needed uncondtionally for the headers
+LLVM_COMPONENTS=( libcxx{abi,} )
+llvm.org_set_globals
+
+LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
+SLOT="0"
+KEYWORDS=""
+IUSE="+libunwind +static-libs test elibc_musl"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+	libunwind? (
+		|| (
+			>=sys-libs/libunwind-1.0.1-r1[static-libs?,${MULTILIB_USEDEP}]
+			>=sys-libs/llvm-libunwind-3.9.0-r1[static-libs?,${MULTILIB_USEDEP}]
+		)
+	)"
+# llvm-6 for new lit options
+DEPEND="${RDEPEND}
+	>=sys-devel/llvm-6"
+BDEPEND="
+	test? ( >=sys-devel/clang-3.9.0
+		$(python_gen_any_dep 'dev-python/lit[${PYTHON_USEDEP}]') )"
+
+# least intrusive of all
+CMAKE_BUILD_TYPE=RelWithDebInfo
+
+python_check_deps() {
+	has_version "dev-python/lit[${PYTHON_USEDEP}]"
+}
+
+pkg_setup() {
+	llvm_pkg_setup
+	use test && python-any-r1_pkg_setup
+}
+
+multilib_src_configure() {
+	# link against compiler-rt instead of libgcc if we are using clang with libunwind
+	local want_compiler_rt=OFF
+	if use libunwind && tc-is-clang; then
+		local compiler_rt=$($(tc-getCC) ${CFLAGS} ${CPPFLAGS} \
+			${LDFLAGS} -print-libgcc-file-name)
+		if [[ ${compiler_rt} == *libclang_rt* ]]; then
+			want_compiler_rt=ON
+		fi
+	fi
+
+	local libdir=$(get_libdir)
+	local mycmakeargs=(
+		-DLIBCXXABI_LIBDIR_SUFFIX=${libdir#lib}
+		-DLIBCXXABI_ENABLE_SHARED=ON
+		-DLIBCXXABI_ENABLE_STATIC=$(usex static-libs)
+		-DLIBCXXABI_USE_LLVM_UNWINDER=$(usex libunwind)
+		-DLIBCXXABI_INCLUDE_TESTS=$(usex test)
+		-DLIBCXXABI_USE_COMPILER_RT=${want_compiler_rt}
+
+		-DLIBCXXABI_LIBCXX_INCLUDES="${WORKDIR}"/libcxx/include
+		# upstream is omitting standard search path for this
+		# probably because gcc & clang are bundling their own unwind.h
+		-DLIBCXXABI_LIBUNWIND_INCLUDES="${EPREFIX}"/usr/include
+	)
+	if use test; then
+		local clang_path=$(type -P "${CHOST:+${CHOST}-}clang" 2>/dev/null)
+		local jobs=${LIT_JOBS:-$(makeopts_jobs "${MAKEOPTS}" "$(get_nproc)")}
+
+		[[ -n ${clang_path} ]] || die "Unable to find ${CHOST}-clang for tests"
+
+		mycmakeargs+=(
+			-DLLVM_EXTERNAL_LIT="${EPREFIX}/usr/bin/lit"
+			-DLLVM_LIT_ARGS="-vv;-j;${jobs};--param=cxx_under_test=${clang_path}"
+		)
+	fi
+	cmake-utils_src_configure
+}
+
+build_libcxx() {
+	local -x LDFLAGS="${LDFLAGS} -L${BUILD_DIR}/$(get_libdir)"
+	local CMAKE_USE_DIR=${WORKDIR}/libcxx
+	local BUILD_DIR=${BUILD_DIR}/libcxx
+	local mycmakeargs=(
+		-DLIBCXX_LIBDIR_SUFFIX=
+		-DLIBCXX_ENABLE_SHARED=OFF
+		-DLIBCXX_ENABLE_STATIC=ON
+		-DLIBCXX_ENABLE_EXPERIMENTAL_LIBRARY=OFF
+		-DLIBCXX_CXX_ABI=libcxxabi
+		-DLIBCXX_CXX_ABI_INCLUDE_PATHS="${S}"/include
+		-DLIBCXX_ENABLE_ABI_LINKER_SCRIPT=OFF
+		-DLIBCXX_HAS_MUSL_LIBC=$(usex elibc_musl)
+		-DLIBCXX_HAS_GCC_S_LIB=OFF
+		-DLIBCXX_INCLUDE_TESTS=OFF
+	)
+
+	cmake-utils_src_configure
+	cmake-utils_src_compile
+}
+
+multilib_src_test() {
+	# build a local copy of libc++ for testing to avoid circular dep
+	build_libcxx
+	mv "${BUILD_DIR}"/libcxx/lib/libc++* "${BUILD_DIR}/$(get_libdir)/" || die
+
+	local -x LIT_PRESERVES_TMP=1
+	cmake-utils_src_make check-libcxxabi
+}
+
+multilib_src_install_all() {
+	insinto /usr/include/libcxxabi
+	doins -r include/.
+}
diff --git a/sys-libs/libomp/libomp-11.0.0.9999.ebuild b/sys-libs/libomp/libomp-11.0.0.9999.ebuild
new file mode 100644
index 000000000000..763579d72517
--- /dev/null
+++ b/sys-libs/libomp/libomp-11.0.0.9999.ebuild
@@ -0,0 +1,106 @@
+# Copyright 1999-2020 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=7
+
+PYTHON_COMPAT=( python{2_7,3_{6,7}} )
+inherit cmake-multilib linux-info llvm.org multiprocessing python-any-r1
+
+DESCRIPTION="OpenMP runtime library for LLVM/clang compiler"
+HOMEPAGE="https://openmp.llvm.org"
+LLVM_COMPONENTS=( openmp )
+llvm.org_set_globals
+
+LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
+SLOT="0"
+KEYWORDS=""
+IUSE="cuda hwloc kernel_linux offload ompt test"
+# CUDA works only with the x86_64 ABI
+REQUIRED_USE="offload? ( cuda? ( abi_x86_64 ) )"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+	hwloc? ( sys-apps/hwloc:0=[${MULTILIB_USEDEP}] )
+	offload? (
+		virtual/libelf:=[${MULTILIB_USEDEP}]
+		virtual/libffi:=[${MULTILIB_USEDEP}]
+		cuda? ( dev-util/nvidia-cuda-toolkit:= )
+	)"
+# tests:
+# - dev-python/lit provides the test runner
+# - sys-devel/llvm provide test utils (e.g. FileCheck)
+# - sys-devel/clang provides the compiler to run tests
+DEPEND="${RDEPEND}"
+BDEPEND="dev-lang/perl
+	offload? ( virtual/pkgconfig[${MULTILIB_USEDEP}] )
+	test? (
+		$(python_gen_any_dep 'dev-python/lit[${PYTHON_USEDEP}]')
+		>=sys-devel/clang-6
+	)"
+
+# least intrusive of all
+CMAKE_BUILD_TYPE=RelWithDebInfo
+
+python_check_deps() {
+	has_version "dev-python/lit[${PYTHON_USEDEP}]"
+}
+
+kernel_pds_check() {
+	if use kernel_linux && kernel_is -lt 4 15 && kernel_is -ge 4 13; then
+		local CONFIG_CHECK="~!SCHED_PDS"
+		local ERROR_SCHED_PDS="\
+PDS scheduler versions >= 0.98c < 0.98i (e.g. used in kernels >= 4.13-pf11
+< 4.14-pf9) do not implement sched_yield() call which may result in horrible
+performance problems with libomp. If you are using one of the specified
+kernel versions, you may want to disable the PDS scheduler."
+
+		check_extra_config
+	fi
+}
+
+pkg_pretend() {
+	kernel_pds_check
+}
+
+pkg_setup() {
+	use test && python-any-r1_pkg_setup
+}
+
+multilib_src_configure() {
+	local libdir="$(get_libdir)"
+	local mycmakeargs=(
+		-DOPENMP_LIBDIR_SUFFIX="${libdir#lib}"
+
+		-DLIBOMP_USE_HWLOC=$(usex hwloc)
+		-DLIBOMP_OMPT_SUPPORT=$(usex ompt)
+
+		-DOPENMP_ENABLE_LIBOMPTARGET=$(usex offload)
+
+		# do not install libgomp.so & libiomp5.so aliases
+		-DLIBOMP_INSTALL_ALIASES=OFF
+		# disable unnecessary hack copying stuff back to srcdir
+		-DLIBOMP_COPY_EXPORTS=OFF
+	)
+	use offload && mycmakeargs+=(
+		# this is non-fatal and libomp checks for CUDA conditionally
+		# to ABI, so we can just ignore passing the wrong value
+		# on non-amd64 ABIs
+		-DCMAKE_DISABLE_FIND_PACKAGE_CUDA=$(usex !cuda)
+	)
+	use test && mycmakeargs+=(
+		# this project does not use standard LLVM cmake macros
+		-DOPENMP_LLVM_LIT_EXECUTABLE="${EPREFIX}/usr/bin/lit"
+		-DOPENMP_LIT_ARGS="-vv;-j;${LIT_JOBS:-$(makeopts_jobs "${MAKEOPTS}" "$(get_nproc)")}"
+
+		-DOPENMP_TEST_C_COMPILER="$(type -P "${CHOST}-clang")"
+		-DOPENMP_TEST_CXX_COMPILER="$(type -P "${CHOST}-clang++")"
+	)
+	cmake-utils_src_configure
+}
+
+multilib_src_test() {
+	# respect TMPDIR!
+	local -x LIT_PRESERVES_TMP=1
+
+	cmake-utils_src_make check-libomp
+}
diff --git a/sys-libs/llvm-libunwind/llvm-libunwind-11.0.0.9999.ebuild b/sys-libs/llvm-libunwind/llvm-libunwind-11.0.0.9999.ebuild
new file mode 100644
index 000000000000..3891515f46e9
--- /dev/null
+++ b/sys-libs/llvm-libunwind/llvm-libunwind-11.0.0.9999.ebuild
@@ -0,0 +1,126 @@
+# Copyright 1999-2020 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=7
+
+PYTHON_COMPAT=( python{2_7,3_{6,7}} )
+inherit cmake-multilib llvm llvm.org multiprocessing python-any-r1
+
+DESCRIPTION="C++ runtime stack unwinder from LLVM"
+HOMEPAGE="https://github.com/llvm-mirror/libunwind"
+LLVM_COMPONENTS=( libunwind )
+LLVM_TEST_COMPONENTS=( libcxx{,abi} )
+llvm.org_set_globals
+
+LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
+SLOT="0"
+KEYWORDS=""
+IUSE="debug +static-libs test"
+RESTRICT="!test? ( test )"
+
+RDEPEND="!sys-libs/libunwind"
+# llvm-6 for new lit options
+DEPEND="
+	>=sys-devel/llvm-6"
+BDEPEND="
+	test? ( >=sys-devel/clang-3.9.0
+		$(python_gen_any_dep 'dev-python/lit[${PYTHON_USEDEP}]') )"
+
+# least intrusive of all
+CMAKE_BUILD_TYPE=RelWithDebInfo
+
+python_check_deps() {
+	has_version "dev-python/lit[${PYTHON_USEDEP}]"
+}
+
+pkg_setup() {
+	use test && python-any-r1_pkg_setup
+}
+
+multilib_src_configure() {
+	local libdir=$(get_libdir)
+
+	local mycmakeargs=(
+		-DLLVM_LIBDIR_SUFFIX=${libdir#lib}
+		-DLIBUNWIND_ENABLE_ASSERTIONS=$(usex debug)
+		-DLIBUNWIND_ENABLE_STATIC=$(usex static-libs)
+		-DLLVM_INCLUDE_TESTS=$(usex test)
+
+		# support non-native unwinding; given it's small enough,
+		# enable it unconditionally
+		-DLIBUNWIND_ENABLE_CROSS_UNWINDING=ON
+	)
+	if use test; then
+		local clang_path=$(type -P "${CHOST:+${CHOST}-}clang" 2>/dev/null)
+		local jobs=${LIT_JOBS:-$(makeopts_jobs "${MAKEOPTS}" "$(get_nproc)")}
+
+		[[ -n ${clang_path} ]] || die "Unable to find ${CHOST}-clang for tests"
+
+		mycmakeargs+=(
+			-DLLVM_EXTERNAL_LIT="${EPREFIX}/usr/bin/lit"
+			-DLLVM_LIT_ARGS="-vv;-j;${jobs};--param=cxx_under_test=${clang_path}"
+			-DLIBUNWIND_LIBCXX_PATH="${WORKDIR}/libcxx"
+		)
+	fi
+
+	cmake-utils_src_configure
+}
+
+build_libcxxabi() {
+	local -x LDFLAGS="${LDFLAGS} -L${BUILD_DIR}/$(get_libdir)"
+	local CMAKE_USE_DIR=${WORKDIR}/libcxxabi
+	local BUILD_DIR=${BUILD_DIR}/libcxxabi
+	local mycmakeargs=(
+		-DLIBCXXABI_LIBDIR_SUFFIX=
+		-DLIBCXXABI_ENABLE_SHARED=OFF
+		-DLIBCXXABI_ENABLE_STATIC=ONF
+		-DLIBCXXABI_USE_LLVM_UNWINDER=ON
+		-DLIBCXXABI_INCLUDE_TESTS=OFF
+
+		-DLIBCXXABI_LIBCXX_INCLUDES="${WORKDIR}"/libcxx/include
+		-DLIBCXXABI_LIBUNWIND_INCLUDES="${S}"/include
+	)
+
+	cmake-utils_src_configure
+	cmake-utils_src_compile
+}
+
+build_libcxx() {
+	local -x LDFLAGS="${LDFLAGS} -L${BUILD_DIR}/libcxxabi/lib -L${BUILD_DIR}/$(get_libdir)"
+	local CMAKE_USE_DIR=${WORKDIR}/libcxx
+	local BUILD_DIR=${BUILD_DIR}/libcxx
+	local mycmakeargs=(
+		-DLIBCXX_LIBDIR_SUFFIX=
+		-DLIBCXX_ENABLE_SHARED=OFF
+		-DLIBCXX_ENABLE_STATIC=ON
+		-DLIBCXX_ENABLE_EXPERIMENTAL_LIBRARY=OFF
+		-DLIBCXXABI_USE_LLVM_UNWINDER=ON
+		-DLIBCXX_CXX_ABI=libcxxabi
+		-DLIBCXX_CXX_ABI_INCLUDE_PATHS="${WORKDIR}"/libcxxabi/include
+		-DLIBCXX_ENABLE_ABI_LINKER_SCRIPT=OFF
+		-DLIBCXX_HAS_MUSL_LIBC=$(usex elibc_musl)
+		-DLIBCXX_HAS_GCC_S_LIB=OFF
+		-DLIBCXX_INCLUDE_TESTS=OFF
+	)
+
+	cmake-utils_src_configure
+	cmake-utils_src_compile
+}
+
+multilib_src_test() {
+	# build local copies of libc++ & libc++abi for testing to avoid
+	# circular deps
+	build_libcxxabi
+	build_libcxx
+	mv "${BUILD_DIR}"/libcxx*/lib/libc++* "${BUILD_DIR}/$(get_libdir)/" || die
+
+	local -x LIT_PRESERVES_TMP=1
+	cmake-utils_src_make check-unwind
+}
+
+multilib_src_install() {
+	cmake-utils_src_install
+
+	# install headers like sys-libs/libunwind
+	doheader "${S}"/include/*.h
+}