10 files changed, 996 insertions, 0 deletions
diff --git a/llvm-runtimes/openmp/Manifest b/llvm-runtimes/openmp/Manifest
new file mode 100644
index 000000000000..cea52d17d78a
--- /dev/null
+++ b/llvm-runtimes/openmp/Manifest
@@ -0,0 +1,23 @@
+DIST llvm-gentoo-patchset-15.0.7-r6.tar.xz 25208 BLAKE2B c9fca31a053ee059c3060a94dcf675d472fc1a59b5f927648de58fb4ff20bfc229890f789ed47b3d053bd466b860a0c60a53b4b024a8fe18c776e9a72434d6de SHA512 601cd923711839dca7cb5bfea53ded644777c6340265a797939a53409fd2ca27059a015fd6ca6832e60314699ade27919a9a59dab395cc27f8fdc479a0f3c034
+DIST llvm-project-15.0.7.src.tar.xz 110936452 BLAKE2B f3d277e2029157329e5be78b78af36b0826a1dfd9a337992499bf701e33149665bfc47d5e14978e38f342559629a559f8b2ce328705ba34fdf6830f5ae9721a5 SHA512 4836d3603f32e8e54434cbfa8ef33d9d473ac5dc20ebf9c67132653c73f4524931abd1084655eaee5f20bcfcb91bcc4bbc5c4a0b603ad0c9029c556e14dc4c52
+DIST llvm-project-15.0.7.src.tar.xz.sig 566 BLAKE2B 47dc8c82d86237b80c6d85f83a6c9a6e9e174cf8e7f367b071e0cd9481d7cd408e991337c5624e07f3f370f26387c814f212808575ed1c1b58404d3e3836b7df SHA512 fc6891b440dd1175eb8df3790590af8d36bc92301660f84744ae15123475aeb900a151e6a8e7998ded27ec4d86871903ad0b89cd61164943054c2e3bc8d8beb2
+DIST llvm-project-16.0.6.src.tar.xz 118013488 BLAKE2B 95192d39cbd2914e5609db365965f1c00bfea6c2d653b3996bd2acef8a2b37e37f6fc8a9d2b65711ad72657e0ef52c42f733053cf65051e7822f27396c30406d SHA512 89a67ebfbbc764cc456e8825ecfa90707741f8835b1b2adffae0b227ab1fe5ca9cce75b0efaffc9ca8431cae528dc54fd838867a56a2b645344d9e82d19ab1b7
+DIST llvm-project-16.0.6.src.tar.xz.sig 566 BLAKE2B 2060cebd5ed57cb8a86a44238c43dfd4b921649298b10c3d19da308374c1e49869174294e29943c2af459fe06428264e26881d6c1288ebbc48686cc2cf467c7a SHA512 ca249262c7102e0889ec1bdc6f71a3a6f0e7e5d5fbab8abcd6fccd2871e7955eff7af5b055a76006097baf0dfaf2f5069eff3035b3107fc552abdb2481b21447
+DIST llvm-project-17.0.6.src.tar.xz 127838860 BLAKE2B d6ede1a9fda8756995c3e0654111941649e15794179641806f18919f1dc68c41ca0cabd5693b5096d05dccc3a391cd20d34af1137bf8af92ed3117a1ce84d1b2 SHA512 6d85bf749e0d77553cc215cbfa61cec4ac4f4f652847f56f946b6a892a99a5ea40b6ab8b39a9708a035001f007986941ccf17e4635260a8b0c1fa59e78d41e30
+DIST llvm-project-17.0.6.src.tar.xz.sig 438 BLAKE2B 186e75b6a0fbfe1e85408589c149e1800fcc47d685b74e4260018e05cd08bc793d1d1197c9c50e177eea941a3d0c65cb0c583ce6dae449099b920adf8a508ef7 SHA512 f78c55053a6450625f3e95f52c305110b4468a9854fec75831b65b8d6ceee3c9206ab9e63c4b5fda8be9bd344f72cfbdaae0520ed240abd505e08ebeaa25d340
+DIST llvm-project-18.1.8.src.tar.xz 132067260 BLAKE2B a950492f1dbfb874dff63b1ffef86468169ba2f211a9733ec2d4cf30040f7f277ef00f048bb44dee9f97d7d762f0f241f19e5a2a7b0b49217d3821ddfc8c354f SHA512 25eeee9984c8b4d0fbc240df90f33cbb000d3b0414baff5c8982beafcc5e59e7ef18f6f85d95b3a5f60cb3d4cd4f877c80487b5768bc21bc833f107698ad93db
+DIST llvm-project-18.1.8.src.tar.xz.sig 566 BLAKE2B 6ab0efc5b38d4483f4e32e8b85774b2edd5d88fdf29f23b88eb0b5130a7a7f0e80549612b025f927e92de4a08ff7c292cff224dbda91a5d598244e98f7ad0fbd SHA512 ddfd1e8a06756759af6cbe488c82a6d6a62ba91f3e8a0eb4cece561321824f5d165b08ed91010588790b76e19790931d2651b24dba8567e3b151d3cb43bec25b
+DIST llvm-project-19.1.4.src.tar.xz 141255156 BLAKE2B b99cd8a96e38dbcfb582ee5d2250268df36fb94fa0fd5b3611484094fbd7962051978334d2c623d2ff5a0209dbb2c6c6492be0146507ae982a7d3e9705a689c5 SHA512 a586f8a41dde5e0d9ca6d8c58e9ef2a2e59b70a86d2e2c46106dc31b5c096bb80af0cdbdb486179e9cc676a540099f49a1c2db9e5e84c50362db1f72e9af6906
+DIST llvm-project-19.1.4.src.tar.xz.sig 438 BLAKE2B b0925bdb761046d69779e0b035e29430bc09ef2b81be763aa5c853793631d7b7fdd65eb4dae7a1e3b4daa15d189c24cd1e14f065f79fdbf75429fa34be9b330e SHA512 3fb4a6c7594cb43680860698dac47062dde30de60f515dcecdad63812ea1edfb2cb209d0a7ac2254589c245a95b7c0f571b582e0d4b97a6ae8242563483ea764
+DIST llvm-project-19.1.5.src.tar.xz 141243716 BLAKE2B 228fc66ab688abfc16f31b2cd83163b81ef61604ace21eab69a1776f0dc88cbe8fa831162205849e5be3975a214136399572b4ad1b908986e37b2d38a1a7fa5d SHA512 648854e9c91fdcc5c677ce3800e046f2060b998a45cf9f7eebe02898431b3924f9348b6fc366102cd4fdda72dcb8f32076f98aa69927e0e20b3f1007fba10b22
+DIST llvm-project-19.1.5.src.tar.xz.sig 438 BLAKE2B 1d40a5c5405f99ef86e3360f9ea153afd1ae4001697210fd799a988113e8a3cef39e2c4794edd9332f384d8490f4ce2ab6bee6d98f794f84775807f833b81c0a SHA512 a438c86ce882eb1ac3e50842937068794ed162bb1b7ded68a2fe3ec2ab4f57cc38aee667cfb46afe6da22eef7ed1cb65820a473f63bd5a0dc6aad41df7bfad54
+DIST llvm-project-32f7f0010bca99ee4bd917f57272733fb2bf3bd9.tar.gz 223983502 BLAKE2B fd3e6b0b795abc42568ef98fa774d927029c18838a5d0f34eaa66c37976444a63f2fc5d883f3bf3a98533f51e387936f1c659230f31c757d26153425696a16cd SHA512 65a345ad5b77c627008f759947e5e9f28a62c8992d7146113e0446e5849feaf9088c15c8b22ca0824af5b927d6a417f5326258b489fb8ccea78ec9e0e0fe8fba
+EBUILD openmp-15.0.7-r6.ebuild 3471 BLAKE2B a6878395f003d40944adfcabbf2247e1ab8833ae54d2a16824e5a99edff94f4a985d4fc706964b3f26b0e55166234be5e68aa63b1c5b819d35413e1c8b6438f8 SHA512 4c08ce8624b029cf516b364172616c7d2fa22355d937ca72f76fc881f1539a441302e08c9dad75496e7f0229bca61802ef449ecf429b067eb24118e46978bab9
+EBUILD openmp-16.0.6.ebuild 3984 BLAKE2B b8507f3eea34c530720512140fa811036893bca9a3ebf25b2d2a90d6302759038017b7a9e0999865ede4e6a96a8bb558ffc46e330f34ca0ed60e741747a32259 SHA512 2dea5938ccc1d0e955fc8ff134ff03a54754b063932c5eece47769d21fe29d19ac9135c01d78d76d577faf7ba046548e57306f1a31fa747a392d241131c5707f
+EBUILD openmp-17.0.6.ebuild 4052 BLAKE2B 39b4f5a76895dbd711fc2a72ff7b7216a8afd29017fab649de5326a8a6cf0907f42899de853af60465816279de3780fe7cde33cdb3706a0be12abdbec34266d5 SHA512 66ece92770a60d74785584a4cbcbf7b5ac1e258c60d20d14a7dd8d140f460b343dda8dd67e2d6a91149fa650b42ca574504020e04358d544ae26e66f724911c6
+EBUILD openmp-18.1.8.ebuild 4288 BLAKE2B d7f71535a5accad1abd9eca5986824878b0ff2592e2f29b406fff385a7ce3220f47c71de1374654e68c337abb3aaa569fe86b61f713b1127a72392601c4eb73f SHA512 f1caa0ad69c419000e12afa33ca1e9fb390588e41cdf780e5edb30a334180bd1003db0547bfc292b481b979a65acec3e7a2c6cc48d9cc80e72e675fccc979ab5
+EBUILD openmp-19.1.4.ebuild 2243 BLAKE2B 9387969f89d1416235a3e5b657167aa9de9f5e85a7ced78d3c6049ea4d2cd02aa8ae64ab27003fe999647d73dbaa684ee56166860aa5863921fcf3d1cdb67d62 SHA512 a552e8ec0b51424ba116a068f4a4de07256b02b5c8ee9e578001c347e09248dfc780b59b1052309f871e82ac168d075af57571a1bff851abf520a0833a05a490
+EBUILD openmp-19.1.5.ebuild 2248 BLAKE2B d95258d4cb8e02ea89ecfcc276c448f0b61c33cd287f8ad8afd5a28b2729a4d5b83555f55897352d954fb043b2a0d2febab84599e69ba58a6c7a9f85967f6c2f SHA512 0f3c0a6202973c659f6ec087ff501cd579132c94a3a2d6757be2cf32f0e947e59f3bfda718bd4bd6fd44cee0aa2eabaa3264e715f32e09a20e38c0d133a7053c
+EBUILD openmp-20.0.0.9999.ebuild 2163 BLAKE2B 1eba3d0fc3b379fc31839cba455be9cafb54b1b1a665410a13eb2ec518613f4819e26684ec6983fe2733f54026bda6319f5061ac18cca7befce82028e2263a5a SHA512 ea7f7232725b7b228a23b56819ad1ccd1c83b8f3ec4d4be72731baa9c5b868ddfd25e8bc63b8dda6599a1b45088a1a73a867c4494f12f3bf69c57a853f7b183f
+EBUILD openmp-20.0.0_pre20241207.ebuild 2163 BLAKE2B 1eba3d0fc3b379fc31839cba455be9cafb54b1b1a665410a13eb2ec518613f4819e26684ec6983fe2733f54026bda6319f5061ac18cca7befce82028e2263a5a SHA512 ea7f7232725b7b228a23b56819ad1ccd1c83b8f3ec4d4be72731baa9c5b868ddfd25e8bc63b8dda6599a1b45088a1a73a867c4494f12f3bf69c57a853f7b183f
+MISC metadata.xml 883 BLAKE2B 127e896b82a49633a6866b33ca776ebe2dd149a5d04da4484a53186f219a85db0ab9d826bc1cc61d4df9fa54c9bcc546be070a0b28985174925fd947aa09cca2 SHA512 dc32cae01401feb93eede6506b3955c766ff19b44976fcc67277559b23ac151993377daeed9ba83b2dd71dbdeea330cd1208dcb0c9c5f56be270883b31f9b15f
diff --git a/llvm-runtimes/openmp/metadata.xml b/llvm-runtimes/openmp/metadata.xml
new file mode 100644
index 000000000000..ba8a5232a5a8
--- /dev/null
+++ b/llvm-runtimes/openmp/metadata.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE pkgmetadata SYSTEM "https://www.gentoo.org/dtd/metadata.dtd">
+<pkgmetadata>
+	<maintainer type="person">
+		<email>voyageur@gentoo.org</email>
+		<name>Bernard Cafarelli</name>
+	</maintainer>
+	<maintainer type="project">
+		<email>llvm@gentoo.org</email>
+	</maintainer>
+	<use>
+		<flag name="gdb-plugin">Build OMPD GDB plugin</flag>
+		<flag name="hwloc">Enable CPU affinity support via hwloc</flag>
+		<flag name="offload">Support offloading OpenMP using libomptarget</flag>
+		<flag name="ompt">Enable OpenMP Tools Interface support</flag>
+	</use>
+	<longdescription>The OpenMP subproject of LLVM is intended to contain all of the components required to build an executing OpenMP program that are outside the compiler itself.</longdescription>
+	<upstream>
+		<remote-id type="github">llvm/llvm-project</remote-id>
+	</upstream>
+</pkgmetadata>
diff --git a/llvm-runtimes/openmp/openmp-15.0.7-r6.ebuild b/llvm-runtimes/openmp/openmp-15.0.7-r6.ebuild
new file mode 100644
index 000000000000..74afb845c85e
--- /dev/null
+++ b/llvm-runtimes/openmp/openmp-15.0.7-r6.ebuild
@@ -0,0 +1,133 @@
+# Copyright 1999-2024 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+PYTHON_COMPAT=( python3_{10..11} )
+inherit flag-o-matic cmake-multilib linux-info llvm llvm.org python-any-r1
+
+DESCRIPTION="OpenMP runtime library for LLVM/clang compiler"
+HOMEPAGE="https://openmp.llvm.org"
+
+LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
+SLOT="0/${LLVM_SOABI}"
+KEYWORDS="amd64 arm arm64 ppc64 ~riscv x86 ~amd64-linux ~x64-macos"
+IUSE="
+	debug hwloc offload ompt test
+	llvm_targets_AMDGPU llvm_targets_NVPTX
+"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+	hwloc? ( >=sys-apps/hwloc-2.5:0=[${MULTILIB_USEDEP}] )
+	offload? (
+		virtual/libelf:=[${MULTILIB_USEDEP}]
+		dev-libs/libffi:=[${MULTILIB_USEDEP}]
+		~llvm-core/llvm-${PV}[${MULTILIB_USEDEP}]
+		llvm_targets_AMDGPU? ( dev-libs/rocr-runtime:= )
+	)
+"
+# tests:
+# - dev-python/lit provides the test runner
+# - llvm-core/llvm provide test utils (e.g. FileCheck)
+# - llvm-core/clang provides the compiler to run tests
+DEPEND="
+	${RDEPEND}
+"
+BDEPEND="
+	dev-lang/perl
+	offload? (
+		llvm_targets_AMDGPU? ( llvm-core/clang )
+		llvm_targets_NVPTX? ( llvm-core/clang )
+		virtual/pkgconfig
+	)
+	test? (
+		$(python_gen_any_dep 'dev-python/lit[${PYTHON_USEDEP}]')
+		llvm-core/clang
+	)
+"
+
+LLVM_COMPONENTS=( openmp cmake llvm/include )
+LLVM_PATCHSET=15.0.7-r6
+llvm.org_set_globals
+
+python_check_deps() {
+	python_has_version "dev-python/lit[${PYTHON_USEDEP}]"
+}
+
+kernel_pds_check() {
+	if use kernel_linux && kernel_is -lt 4 15 && kernel_is -ge 4 13; then
+		local CONFIG_CHECK="~!SCHED_PDS"
+		local ERROR_SCHED_PDS="\
+PDS scheduler versions >= 0.98c < 0.98i (e.g. used in kernels >= 4.13-pf11
+< 4.14-pf9) do not implement sched_yield() call which may result in horrible
+performance problems with libomp. If you are using one of the specified
+kernel versions, you may want to disable the PDS scheduler."
+
+		check_extra_config
+	fi
+}
+
+pkg_pretend() {
+	kernel_pds_check
+}
+
+pkg_setup() {
+	use offload && LLVM_MAX_SLOT=${LLVM_MAJOR} llvm_pkg_setup
+	use test && python-any-r1_pkg_setup
+}
+
+multilib_src_configure() {
+	# LTO causes issues in other packages building, #870127
+	filter-lto
+
+	# LLVM_ENABLE_ASSERTIONS=NO does not guarantee this for us, #614844
+	use debug || local -x CPPFLAGS="${CPPFLAGS} -DNDEBUG"
+
+	local libdir="$(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
+	)
+
+	if use offload; then
+		if has "${CHOST%%-*}" aarch64 powerpc64le x86_64; then
+			mycmakeargs+=(
+				-DLIBOMPTARGET_BUILD_AMDGPU_PLUGIN=$(usex llvm_targets_AMDGPU)
+				-DLIBOMPTARGET_BUILD_CUDA_PLUGIN=$(usex llvm_targets_NVPTX)
+			)
+		else
+			mycmakeargs+=(
+				-DLIBOMPTARGET_BUILD_AMDGPU_PLUGIN=OFF
+				-DLIBOMPTARGET_BUILD_CUDA_PLUGIN=OFF
+			)
+		fi
+	fi
+
+	use test && mycmakeargs+=(
+		# this project does not use standard LLVM cmake macros
+		-DOPENMP_LLVM_LIT_EXECUTABLE="${EPREFIX}/usr/bin/lit"
+		-DOPENMP_LIT_ARGS="$(get_lit_flags)"
+
+		-DOPENMP_TEST_C_COMPILER="$(type -P "${CHOST}-clang")"
+		-DOPENMP_TEST_CXX_COMPILER="$(type -P "${CHOST}-clang++")"
+	)
+	addpredict /dev/nvidiactl
+	cmake_src_configure
+}
+
+multilib_src_test() {
+	# respect TMPDIR!
+	local -x LIT_PRESERVES_TMP=1
+
+	cmake_build check-libomp
+}
diff --git a/llvm-runtimes/openmp/openmp-16.0.6.ebuild b/llvm-runtimes/openmp/openmp-16.0.6.ebuild
new file mode 100644
index 000000000000..72b1601886a3
--- /dev/null
+++ b/llvm-runtimes/openmp/openmp-16.0.6.ebuild
@@ -0,0 +1,151 @@
+# Copyright 1999-2024 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+PYTHON_COMPAT=( python3_{10..12} )
+inherit flag-o-matic cmake-multilib linux-info llvm llvm.org
+inherit python-single-r1 toolchain-funcs
+
+DESCRIPTION="OpenMP runtime library for LLVM/clang compiler"
+HOMEPAGE="https://openmp.llvm.org"
+
+LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
+SLOT="0/${LLVM_SOABI}"
+KEYWORDS="amd64 arm arm64 ~loong ppc64 ~riscv x86 ~amd64-linux ~x64-macos"
+IUSE="
+	debug gdb-plugin hwloc offload ompt test
+	llvm_targets_AMDGPU llvm_targets_NVPTX
+"
+REQUIRED_USE="
+	gdb-plugin? ( ${PYTHON_REQUIRED_USE} )
+"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+	gdb-plugin? ( ${PYTHON_DEPS} )
+	hwloc? ( >=sys-apps/hwloc-2.5:0=[${MULTILIB_USEDEP}] )
+	offload? (
+		dev-libs/libffi:=[${MULTILIB_USEDEP}]
+		~llvm-core/llvm-${PV}[${MULTILIB_USEDEP}]
+		llvm_targets_AMDGPU? ( dev-libs/rocr-runtime:= )
+	)
+"
+# tests:
+# - dev-python/lit provides the test runner
+# - llvm-core/llvm provide test utils (e.g. FileCheck)
+# - llvm-core/clang provides the compiler to run tests
+DEPEND="
+	${RDEPEND}
+"
+BDEPEND="
+	dev-lang/perl
+	offload? (
+		llvm_targets_AMDGPU? ( llvm-core/clang )
+		llvm_targets_NVPTX? ( llvm-core/clang )
+		virtual/pkgconfig
+	)
+	test? (
+		${PYTHON_DEPS}
+		$(python_gen_cond_dep '
+			dev-python/lit[${PYTHON_USEDEP}]
+		')
+		llvm-core/clang
+	)
+"
+
+LLVM_COMPONENTS=( openmp cmake llvm/include )
+llvm.org_set_globals
+
+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 offload && LLVM_MAX_SLOT=${LLVM_MAJOR} llvm_pkg_setup
+	if use gdb-plugin || use test; then
+		python-single-r1_pkg_setup
+	fi
+}
+
+multilib_src_configure() {
+	# LTO causes issues in other packages building, #870127
+	filter-lto
+
+	# LLVM_ENABLE_ASSERTIONS=NO does not guarantee this for us, #614844
+	use debug || local -x CPPFLAGS="${CPPFLAGS} -DNDEBUG"
+
+	local build_omptarget=OFF
+	# upstream disallows building libomptarget when sizeof(void*) != 8
+	if use offload &&
+		"$(tc-getCC)" ${CFLAGS} ${CPPFLAGS} -c -x c - -o /dev/null \
+		<<-EOF &>/dev/null
+			int test[sizeof(void *) == 8 ? 1 : -1];
+		EOF
+	then
+		build_omptarget=ON
+	fi
+
+	local libdir="$(get_libdir)"
+	local mycmakeargs=(
+		-DOPENMP_LIBDIR_SUFFIX="${libdir#lib}"
+
+		-DLIBOMP_USE_HWLOC=$(usex hwloc)
+		-DLIBOMP_OMPD_GDB_SUPPORT=$(multilib_native_usex gdb-plugin)
+		-DLIBOMP_OMPT_SUPPORT=$(usex ompt)
+
+		-DOPENMP_ENABLE_LIBOMPTARGET=${build_omptarget}
+
+		# do not install libgomp.so & libiomp5.so aliases
+		-DLIBOMP_INSTALL_ALIASES=OFF
+		# disable unnecessary hack copying stuff back to srcdir
+		-DLIBOMP_COPY_EXPORTS=OFF
+		# prevent trying to access the GPU
+		-DLIBOMPTARGET_AMDGPU_ARCH=LIBOMPTARGET_AMDGPU_ARCH-NOTFOUND
+	)
+
+	if [[ ${build_omptarget} == ON ]]; then
+		if has "${CHOST%%-*}" aarch64 powerpc64le x86_64; then
+			mycmakeargs+=(
+				-DLIBOMPTARGET_BUILD_AMDGPU_PLUGIN=$(usex llvm_targets_AMDGPU)
+				-DLIBOMPTARGET_BUILD_CUDA_PLUGIN=$(usex llvm_targets_NVPTX)
+			)
+		else
+			mycmakeargs+=(
+				-DLIBOMPTARGET_BUILD_AMDGPU_PLUGIN=OFF
+				-DLIBOMPTARGET_BUILD_CUDA_PLUGIN=OFF
+			)
+		fi
+	fi
+
+	use test && mycmakeargs+=(
+		# this project does not use standard LLVM cmake macros
+		-DOPENMP_LLVM_LIT_EXECUTABLE="${EPREFIX}/usr/bin/lit"
+		-DOPENMP_LIT_ARGS="$(get_lit_flags)"
+
+		-DOPENMP_TEST_C_COMPILER="$(type -P "${CHOST}-clang")"
+		-DOPENMP_TEST_CXX_COMPILER="$(type -P "${CHOST}-clang++")"
+	)
+	addpredict /dev/nvidiactl
+	cmake_src_configure
+}
+
+multilib_src_test() {
+	# respect TMPDIR!
+	local -x LIT_PRESERVES_TMP=1
+
+	cmake_build check-libomp
+}
diff --git a/llvm-runtimes/openmp/openmp-17.0.6.ebuild b/llvm-runtimes/openmp/openmp-17.0.6.ebuild
new file mode 100644
index 000000000000..50715455a515
--- /dev/null
+++ b/llvm-runtimes/openmp/openmp-17.0.6.ebuild
@@ -0,0 +1,153 @@
+# Copyright 1999-2024 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+PYTHON_COMPAT=( python3_{10..12} )
+inherit flag-o-matic cmake-multilib linux-info llvm llvm.org
+inherit python-single-r1 toolchain-funcs
+
+DESCRIPTION="OpenMP runtime library for LLVM/clang compiler"
+HOMEPAGE="https://openmp.llvm.org"
+
+LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
+SLOT="0/${LLVM_SOABI}"
+KEYWORDS="amd64 arm arm64 ~loong ppc64 ~riscv x86 ~amd64-linux ~x64-macos"
+IUSE="
+	debug gdb-plugin hwloc offload ompt test
+	llvm_targets_AMDGPU llvm_targets_NVPTX
+"
+REQUIRED_USE="
+	gdb-plugin? ( ${PYTHON_REQUIRED_USE} )
+"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+	gdb-plugin? ( ${PYTHON_DEPS} )
+	hwloc? ( >=sys-apps/hwloc-2.5:0=[${MULTILIB_USEDEP}] )
+	offload? (
+		dev-libs/libffi:=[${MULTILIB_USEDEP}]
+		~llvm-core/llvm-${PV}[${MULTILIB_USEDEP}]
+		llvm_targets_AMDGPU? ( dev-libs/rocr-runtime:= )
+	)
+"
+# tests:
+# - dev-python/lit provides the test runner
+# - llvm-core/llvm provide test utils (e.g. FileCheck)
+# - llvm-core/clang provides the compiler to run tests
+DEPEND="
+	${RDEPEND}
+"
+BDEPEND="
+	dev-lang/perl
+	offload? (
+		llvm_targets_AMDGPU? ( llvm-core/clang )
+		llvm_targets_NVPTX? ( llvm-core/clang )
+		virtual/pkgconfig
+	)
+	test? (
+		${PYTHON_DEPS}
+		$(python_gen_cond_dep '
+			dev-python/lit[${PYTHON_USEDEP}]
+		')
+		llvm-core/clang
+	)
+"
+
+LLVM_COMPONENTS=( openmp cmake llvm/include )
+llvm.org_set_globals
+
+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 offload && LLVM_MAX_SLOT=${LLVM_MAJOR} llvm_pkg_setup
+	if use gdb-plugin || use test; then
+		python-single-r1_pkg_setup
+	fi
+}
+
+multilib_src_configure() {
+	# LTO causes issues in other packages building, #870127
+	filter-lto
+
+	# LLVM_ENABLE_ASSERTIONS=NO does not guarantee this for us, #614844
+	use debug || local -x CPPFLAGS="${CPPFLAGS} -DNDEBUG"
+
+	local build_omptarget=OFF
+	# upstream disallows building libomptarget when sizeof(void*) != 8
+	if use offload &&
+		"$(tc-getCC)" ${CFLAGS} ${CPPFLAGS} -c -x c - -o /dev/null \
+		<<-EOF &>/dev/null
+			int test[sizeof(void *) == 8 ? 1 : -1];
+		EOF
+	then
+		build_omptarget=ON
+	fi
+
+	local libdir="$(get_libdir)"
+	local mycmakeargs=(
+		-DOPENMP_LIBDIR_SUFFIX="${libdir#lib}"
+
+		-DLIBOMP_USE_HWLOC=$(usex hwloc)
+		-DLIBOMP_OMPD_GDB_SUPPORT=$(multilib_native_usex gdb-plugin)
+		-DLIBOMP_OMPT_SUPPORT=$(usex ompt)
+
+		-DOPENMP_ENABLE_LIBOMPTARGET=${build_omptarget}
+
+		# do not install libgomp.so & libiomp5.so aliases
+		-DLIBOMP_INSTALL_ALIASES=OFF
+		# disable unnecessary hack copying stuff back to srcdir
+		-DLIBOMP_COPY_EXPORTS=OFF
+	)
+
+	if [[ ${build_omptarget} == ON ]]; then
+		if has "${CHOST%%-*}" aarch64 powerpc64le x86_64; then
+			mycmakeargs+=(
+				-DLIBOMPTARGET_BUILD_AMDGPU_PLUGIN=$(usex llvm_targets_AMDGPU)
+				-DLIBOMPTARGET_BUILD_CUDA_PLUGIN=$(usex llvm_targets_NVPTX)
+
+				# prevent trying to access the GPU
+				-DLIBOMPTARGET_AMDGPU_ARCH=LIBOMPTARGET_AMDGPU_ARCH-NOTFOUND
+				-DLIBOMPTARGET_NVPTX_ARCH=LIBOMPTARGET_NVPTX_ARCH-NOTFOUND
+			)
+		else
+			mycmakeargs+=(
+				-DLIBOMPTARGET_BUILD_AMDGPU_PLUGIN=OFF
+				-DLIBOMPTARGET_BUILD_CUDA_PLUGIN=OFF
+			)
+		fi
+	fi
+
+	use test && mycmakeargs+=(
+		# this project does not use standard LLVM cmake macros
+		-DOPENMP_LLVM_LIT_EXECUTABLE="${EPREFIX}/usr/bin/lit"
+		-DOPENMP_LIT_ARGS="$(get_lit_flags)"
+
+		-DOPENMP_TEST_C_COMPILER="$(type -P "${CHOST}-clang")"
+		-DOPENMP_TEST_CXX_COMPILER="$(type -P "${CHOST}-clang++")"
+	)
+	addpredict /dev/nvidiactl
+	cmake_src_configure
+}
+
+multilib_src_test() {
+	# respect TMPDIR!
+	local -x LIT_PRESERVES_TMP=1
+
+	cmake_build check-libomp
+}
diff --git a/llvm-runtimes/openmp/openmp-18.1.8.ebuild b/llvm-runtimes/openmp/openmp-18.1.8.ebuild
new file mode 100644
index 000000000000..866ca4a5b663
--- /dev/null
+++ b/llvm-runtimes/openmp/openmp-18.1.8.ebuild
@@ -0,0 +1,161 @@
+# Copyright 1999-2024 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+PYTHON_COMPAT=( python3_{10..13} )
+inherit flag-o-matic cmake-multilib linux-info llvm.org llvm-utils
+inherit python-single-r1 toolchain-funcs
+
+DESCRIPTION="OpenMP runtime library for LLVM/clang compiler"
+HOMEPAGE="https://openmp.llvm.org"
+
+LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
+SLOT="0/${LLVM_SOABI}"
+KEYWORDS="amd64 arm arm64 ~loong ~mips ppc64 ~riscv x86 ~amd64-linux ~x64-macos"
+IUSE="
+	debug gdb-plugin hwloc offload ompt test
+	llvm_targets_AMDGPU llvm_targets_NVPTX
+"
+REQUIRED_USE="
+	gdb-plugin? ( ${PYTHON_REQUIRED_USE} )
+"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+	gdb-plugin? ( ${PYTHON_DEPS} )
+	hwloc? ( >=sys-apps/hwloc-2.5:0=[${MULTILIB_USEDEP}] )
+	offload? (
+		dev-libs/libffi:=[${MULTILIB_USEDEP}]
+		~llvm-core/llvm-${PV}[${MULTILIB_USEDEP}]
+		llvm_targets_AMDGPU? ( dev-libs/rocr-runtime:= )
+	)
+"
+# tests:
+# - dev-python/lit provides the test runner
+# - llvm-core/llvm provide test utils (e.g. FileCheck)
+# - llvm-core/clang provides the compiler to run tests
+DEPEND="
+	${RDEPEND}
+"
+BDEPEND="
+	dev-lang/perl
+	offload? (
+		llvm_targets_AMDGPU? ( llvm-core/clang )
+		llvm_targets_NVPTX? ( llvm-core/clang )
+		virtual/pkgconfig
+	)
+	test? (
+		${PYTHON_DEPS}
+		$(python_gen_cond_dep '
+			dev-python/lit[${PYTHON_USEDEP}]
+		')
+		llvm-core/clang
+	)
+"
+
+LLVM_COMPONENTS=( openmp cmake llvm/include )
+llvm.org_set_globals
+
+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() {
+	if use gdb-plugin || use test; then
+		python-single-r1_pkg_setup
+	fi
+}
+
+multilib_src_configure() {
+	use offload && llvm_prepend_path "${LLVM_MAJOR}"
+
+	# LTO causes issues in other packages building, #870127
+	filter-lto
+
+	# LLVM_ENABLE_ASSERTIONS=NO does not guarantee this for us, #614844
+	use debug || local -x CPPFLAGS="${CPPFLAGS} -DNDEBUG"
+
+	local build_omptarget=OFF
+	# upstream disallows building libomptarget when sizeof(void*) != 8
+	if use offload &&
+		"$(tc-getCC)" ${CFLAGS} ${CPPFLAGS} -c -x c - -o /dev/null \
+		<<-EOF &>/dev/null
+			int test[sizeof(void *) == 8 ? 1 : -1];
+		EOF
+	then
+		build_omptarget=ON
+	fi
+
+	local libdir="$(get_libdir)"
+	local mycmakeargs=(
+		-DOPENMP_LIBDIR_SUFFIX="${libdir#lib}"
+
+		-DLIBOMP_USE_HWLOC=$(usex hwloc)
+		-DLIBOMP_OMPD_GDB_SUPPORT=$(multilib_native_usex gdb-plugin)
+		-DLIBOMP_OMPT_SUPPORT=$(usex ompt)
+
+		-DOPENMP_ENABLE_LIBOMPTARGET=${build_omptarget}
+
+		# do not install libgomp.so & libiomp5.so aliases
+		-DLIBOMP_INSTALL_ALIASES=OFF
+		# disable unnecessary hack copying stuff back to srcdir
+		-DLIBOMP_COPY_EXPORTS=OFF
+	)
+
+	if [[ ${build_omptarget} == ON ]]; then
+		local ffi_cflags=$($(tc-getPKG_CONFIG) --cflags-only-I libffi)
+		local ffi_ldflags=$($(tc-getPKG_CONFIG) --libs-only-L libffi)
+		mycmakeargs+=(
+			-DFFI_INCLUDE_DIR="${ffi_cflags#-I}"
+			-DFFI_LIBRARY_DIR="${ffi_ldflags#-L}"
+		)
+
+		if has "${CHOST%%-*}" aarch64 powerpc64le x86_64; then
+			mycmakeargs+=(
+				-DLIBOMPTARGET_BUILD_AMDGPU_PLUGIN=$(usex llvm_targets_AMDGPU)
+				-DLIBOMPTARGET_BUILD_CUDA_PLUGIN=$(usex llvm_targets_NVPTX)
+
+				# prevent trying to access the GPU
+				-DLIBOMPTARGET_AMDGPU_ARCH=LIBOMPTARGET_AMDGPU_ARCH-NOTFOUND
+				-DLIBOMPTARGET_NVPTX_ARCH=LIBOMPTARGET_NVPTX_ARCH-NOTFOUND
+			)
+		else
+			mycmakeargs+=(
+				-DLIBOMPTARGET_BUILD_AMDGPU_PLUGIN=OFF
+				-DLIBOMPTARGET_BUILD_CUDA_PLUGIN=OFF
+			)
+		fi
+	fi
+
+	use test && mycmakeargs+=(
+		# this project does not use standard LLVM cmake macros
+		-DOPENMP_LLVM_LIT_EXECUTABLE="${EPREFIX}/usr/bin/lit"
+		-DOPENMP_LIT_ARGS="$(get_lit_flags)"
+
+		-DOPENMP_TEST_C_COMPILER="$(type -P "${CHOST}-clang")"
+		-DOPENMP_TEST_CXX_COMPILER="$(type -P "${CHOST}-clang++")"
+	)
+	addpredict /dev/nvidiactl
+	cmake_src_configure
+}
+
+multilib_src_test() {
+	# respect TMPDIR!
+	local -x LIT_PRESERVES_TMP=1
+
+	cmake_build check-libomp
+}
diff --git a/llvm-runtimes/openmp/openmp-19.1.4.ebuild b/llvm-runtimes/openmp/openmp-19.1.4.ebuild
new file mode 100644
index 000000000000..749cc58b9878
--- /dev/null
+++ b/llvm-runtimes/openmp/openmp-19.1.4.ebuild
@@ -0,0 +1,89 @@
+# Copyright 1999-2024 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+PYTHON_COMPAT=( python3_{10..13} )
+inherit flag-o-matic cmake-multilib linux-info llvm.org python-single-r1
+
+DESCRIPTION="OpenMP runtime library for LLVM/clang compiler"
+HOMEPAGE="https://openmp.llvm.org"
+
+LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
+SLOT="0/${LLVM_SOABI}"
+KEYWORDS="amd64 arm arm64 ~loong ~mips ppc64 ~riscv x86 ~amd64-linux ~x64-macos"
+IUSE="debug gdb-plugin hwloc ompt test"
+REQUIRED_USE="
+	gdb-plugin? ( ${PYTHON_REQUIRED_USE} )
+"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+	gdb-plugin? ( ${PYTHON_DEPS} )
+	hwloc? ( >=sys-apps/hwloc-2.5:0=[${MULTILIB_USEDEP}] )
+"
+# tests:
+# - dev-python/lit provides the test runner
+# - llvm-core/llvm provide test utils (e.g. FileCheck)
+# - llvm-core/clang provides the compiler to run tests
+DEPEND="
+	${RDEPEND}
+"
+BDEPEND="
+	dev-lang/perl
+	test? (
+		${PYTHON_DEPS}
+		$(python_gen_cond_dep '
+			dev-python/lit[${PYTHON_USEDEP}]
+		')
+		llvm-core/clang
+	)
+"
+
+LLVM_COMPONENTS=( openmp cmake llvm/include )
+llvm.org_set_globals
+
+pkg_setup() {
+	if use gdb-plugin || use test; then
+		python-single-r1_pkg_setup
+	fi
+}
+
+multilib_src_configure() {
+	# LTO causes issues in other packages building, #870127
+	filter-lto
+
+	# LLVM_ENABLE_ASSERTIONS=NO does not guarantee this for us, #614844
+	use debug || local -x CPPFLAGS="${CPPFLAGS} -DNDEBUG"
+
+	local libdir="$(get_libdir)"
+	local mycmakeargs=(
+		-DOPENMP_LIBDIR_SUFFIX="${libdir#lib}"
+
+		-DLIBOMP_USE_HWLOC=$(usex hwloc)
+		-DLIBOMP_OMPD_GDB_SUPPORT=$(multilib_native_usex gdb-plugin)
+		-DLIBOMP_OMPT_SUPPORT=$(usex ompt)
+
+		# 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 test && mycmakeargs+=(
+		# this project does not use standard LLVM cmake macros
+		-DOPENMP_LLVM_LIT_EXECUTABLE="${EPREFIX}/usr/bin/lit"
+		-DOPENMP_LIT_ARGS="$(get_lit_flags)"
+
+		-DOPENMP_TEST_C_COMPILER="$(type -P "${CHOST}-clang")"
+		-DOPENMP_TEST_CXX_COMPILER="$(type -P "${CHOST}-clang++")"
+	)
+	cmake_src_configure
+}
+
+multilib_src_test() {
+	# respect TMPDIR!
+	local -x LIT_PRESERVES_TMP=1
+
+	cmake_build check-libomp
+}
diff --git a/llvm-runtimes/openmp/openmp-19.1.5.ebuild b/llvm-runtimes/openmp/openmp-19.1.5.ebuild
new file mode 100644
index 000000000000..c82915160dbc
--- /dev/null
+++ b/llvm-runtimes/openmp/openmp-19.1.5.ebuild
@@ -0,0 +1,89 @@
+# Copyright 1999-2024 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+PYTHON_COMPAT=( python3_{10..13} )
+inherit flag-o-matic cmake-multilib linux-info llvm.org python-single-r1
+
+DESCRIPTION="OpenMP runtime library for LLVM/clang compiler"
+HOMEPAGE="https://openmp.llvm.org"
+
+LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
+SLOT="0/${LLVM_SOABI}"
+KEYWORDS="~amd64 ~arm ~arm64 ~loong ~mips ~ppc64 ~riscv ~x86 ~amd64-linux ~x64-macos"
+IUSE="debug gdb-plugin hwloc ompt test"
+REQUIRED_USE="
+	gdb-plugin? ( ${PYTHON_REQUIRED_USE} )
+"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+	gdb-plugin? ( ${PYTHON_DEPS} )
+	hwloc? ( >=sys-apps/hwloc-2.5:0=[${MULTILIB_USEDEP}] )
+"
+# tests:
+# - dev-python/lit provides the test runner
+# - llvm-core/llvm provide test utils (e.g. FileCheck)
+# - llvm-core/clang provides the compiler to run tests
+DEPEND="
+	${RDEPEND}
+"
+BDEPEND="
+	dev-lang/perl
+	test? (
+		${PYTHON_DEPS}
+		$(python_gen_cond_dep '
+			dev-python/lit[${PYTHON_USEDEP}]
+		')
+		llvm-core/clang
+	)
+"
+
+LLVM_COMPONENTS=( openmp cmake llvm/include )
+llvm.org_set_globals
+
+pkg_setup() {
+	if use gdb-plugin || use test; then
+		python-single-r1_pkg_setup
+	fi
+}
+
+multilib_src_configure() {
+	# LTO causes issues in other packages building, #870127
+	filter-lto
+
+	# LLVM_ENABLE_ASSERTIONS=NO does not guarantee this for us, #614844
+	use debug || local -x CPPFLAGS="${CPPFLAGS} -DNDEBUG"
+
+	local libdir="$(get_libdir)"
+	local mycmakeargs=(
+		-DOPENMP_LIBDIR_SUFFIX="${libdir#lib}"
+
+		-DLIBOMP_USE_HWLOC=$(usex hwloc)
+		-DLIBOMP_OMPD_GDB_SUPPORT=$(multilib_native_usex gdb-plugin)
+		-DLIBOMP_OMPT_SUPPORT=$(usex ompt)
+
+		# 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 test && mycmakeargs+=(
+		# this project does not use standard LLVM cmake macros
+		-DOPENMP_LLVM_LIT_EXECUTABLE="${EPREFIX}/usr/bin/lit"
+		-DOPENMP_LIT_ARGS="$(get_lit_flags)"
+
+		-DOPENMP_TEST_C_COMPILER="$(type -P "${CHOST}-clang")"
+		-DOPENMP_TEST_CXX_COMPILER="$(type -P "${CHOST}-clang++")"
+	)
+	cmake_src_configure
+}
+
+multilib_src_test() {
+	# respect TMPDIR!
+	local -x LIT_PRESERVES_TMP=1
+
+	cmake_build check-libomp
+}
diff --git a/llvm-runtimes/openmp/openmp-20.0.0.9999.ebuild b/llvm-runtimes/openmp/openmp-20.0.0.9999.ebuild
new file mode 100644
index 000000000000..ea3715dad3ed
--- /dev/null
+++ b/llvm-runtimes/openmp/openmp-20.0.0.9999.ebuild
@@ -0,0 +1,88 @@
+# Copyright 1999-2024 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+PYTHON_COMPAT=( python3_{10..13} )
+inherit flag-o-matic cmake-multilib linux-info llvm.org python-single-r1
+
+DESCRIPTION="OpenMP runtime library for LLVM/clang compiler"
+HOMEPAGE="https://openmp.llvm.org"
+
+LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
+SLOT="0/${LLVM_SOABI}"
+IUSE="+debug gdb-plugin hwloc ompt test"
+REQUIRED_USE="
+	gdb-plugin? ( ${PYTHON_REQUIRED_USE} )
+"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+	gdb-plugin? ( ${PYTHON_DEPS} )
+	hwloc? ( >=sys-apps/hwloc-2.5:0=[${MULTILIB_USEDEP}] )
+"
+# tests:
+# - dev-python/lit provides the test runner
+# - llvm-core/llvm provide test utils (e.g. FileCheck)
+# - llvm-core/clang provides the compiler to run tests
+DEPEND="
+	${RDEPEND}
+"
+BDEPEND="
+	dev-lang/perl
+	test? (
+		${PYTHON_DEPS}
+		$(python_gen_cond_dep '
+			dev-python/lit[${PYTHON_USEDEP}]
+		')
+		llvm-core/clang
+	)
+"
+
+LLVM_COMPONENTS=( openmp cmake llvm/include )
+llvm.org_set_globals
+
+pkg_setup() {
+	if use gdb-plugin || use test; then
+		python-single-r1_pkg_setup
+	fi
+}
+
+multilib_src_configure() {
+	# LTO causes issues in other packages building, #870127
+	filter-lto
+
+	# LLVM_ENABLE_ASSERTIONS=NO does not guarantee this for us, #614844
+	use debug || local -x CPPFLAGS="${CPPFLAGS} -DNDEBUG"
+
+	local libdir="$(get_libdir)"
+	local mycmakeargs=(
+		-DOPENMP_LIBDIR_SUFFIX="${libdir#lib}"
+
+		-DLIBOMP_USE_HWLOC=$(usex hwloc)
+		-DLIBOMP_OMPD_GDB_SUPPORT=$(multilib_native_usex gdb-plugin)
+		-DLIBOMP_OMPT_SUPPORT=$(usex ompt)
+
+		# 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 test && mycmakeargs+=(
+		# this project does not use standard LLVM cmake macros
+		-DOPENMP_LLVM_LIT_EXECUTABLE="${EPREFIX}/usr/bin/lit"
+		-DOPENMP_LIT_ARGS="$(get_lit_flags)"
+
+		-DOPENMP_TEST_C_COMPILER="$(type -P "${CHOST}-clang")"
+		-DOPENMP_TEST_CXX_COMPILER="$(type -P "${CHOST}-clang++")"
+	)
+	cmake_src_configure
+}
+
+multilib_src_test() {
+	# respect TMPDIR!
+	local -x LIT_PRESERVES_TMP=1
+
+	cmake_build check-libomp
+}
diff --git a/llvm-runtimes/openmp/openmp-20.0.0_pre20241207.ebuild b/llvm-runtimes/openmp/openmp-20.0.0_pre20241207.ebuild
new file mode 100644
index 000000000000..ea3715dad3ed
--- /dev/null
+++ b/llvm-runtimes/openmp/openmp-20.0.0_pre20241207.ebuild
@@ -0,0 +1,88 @@
+# Copyright 1999-2024 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+PYTHON_COMPAT=( python3_{10..13} )
+inherit flag-o-matic cmake-multilib linux-info llvm.org python-single-r1
+
+DESCRIPTION="OpenMP runtime library for LLVM/clang compiler"
+HOMEPAGE="https://openmp.llvm.org"
+
+LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
+SLOT="0/${LLVM_SOABI}"
+IUSE="+debug gdb-plugin hwloc ompt test"
+REQUIRED_USE="
+	gdb-plugin? ( ${PYTHON_REQUIRED_USE} )
+"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+	gdb-plugin? ( ${PYTHON_DEPS} )
+	hwloc? ( >=sys-apps/hwloc-2.5:0=[${MULTILIB_USEDEP}] )
+"
+# tests:
+# - dev-python/lit provides the test runner
+# - llvm-core/llvm provide test utils (e.g. FileCheck)
+# - llvm-core/clang provides the compiler to run tests
+DEPEND="
+	${RDEPEND}
+"
+BDEPEND="
+	dev-lang/perl
+	test? (
+		${PYTHON_DEPS}
+		$(python_gen_cond_dep '
+			dev-python/lit[${PYTHON_USEDEP}]
+		')
+		llvm-core/clang
+	)
+"
+
+LLVM_COMPONENTS=( openmp cmake llvm/include )
+llvm.org_set_globals
+
+pkg_setup() {
+	if use gdb-plugin || use test; then
+		python-single-r1_pkg_setup
+	fi
+}
+
+multilib_src_configure() {
+	# LTO causes issues in other packages building, #870127
+	filter-lto
+
+	# LLVM_ENABLE_ASSERTIONS=NO does not guarantee this for us, #614844
+	use debug || local -x CPPFLAGS="${CPPFLAGS} -DNDEBUG"
+
+	local libdir="$(get_libdir)"
+	local mycmakeargs=(
+		-DOPENMP_LIBDIR_SUFFIX="${libdir#lib}"
+
+		-DLIBOMP_USE_HWLOC=$(usex hwloc)
+		-DLIBOMP_OMPD_GDB_SUPPORT=$(multilib_native_usex gdb-plugin)
+		-DLIBOMP_OMPT_SUPPORT=$(usex ompt)
+
+		# 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 test && mycmakeargs+=(
+		# this project does not use standard LLVM cmake macros
+		-DOPENMP_LLVM_LIT_EXECUTABLE="${EPREFIX}/usr/bin/lit"
+		-DOPENMP_LIT_ARGS="$(get_lit_flags)"
+
+		-DOPENMP_TEST_C_COMPILER="$(type -P "${CHOST}-clang")"
+		-DOPENMP_TEST_CXX_COMPILER="$(type -P "${CHOST}-clang++")"
+	)
+	cmake_src_configure
+}
+
+multilib_src_test() {
+	# respect TMPDIR!
+	local -x LIT_PRESERVES_TMP=1
+
+	cmake_build check-libomp
+}