llvm-runtimes/flang-rt: Add 21.0.0_pre20250329 snapshot

Signed-off-by: Michał Górny <mgorny@gentoo.org>

llvm-runtimes/flang-rt/Manifest

@@ -1,2 +1,3 @@
 DIST llvm-project-1c3a9a853ce68c3c539e7cab21380b9d8b18f426.tar.gz 229448743 BLAKE2B c1eacc2ed05c460f56cf83f16b982e3fa4ac530483d7cf003034239aff3b3dbffbdd3042a3f295a83ec94fcf32f802714e4937fd3761a5e03d4ed1b4093e81bf SHA512 98b7e9fa330a6fce33ca9757caf5d2e41d0b73117cb24b2aed880274c2d6f8a8c1a0028dd0e773fa42deb61dbe3b9dd4fb2f44e50814b966fcdeae8e5b417e6d
 DIST llvm-project-1d133420dc512487e2be0e9d86755f2a7c3497a7.tar.gz 229268288 BLAKE2B aca79bcca631deeab429a03cd2732d78d8ecf0c9615bce181445ed875436806609dc85a57d4f97109492833d620d060ea93fed450a4912c2d94597aeabf84974 SHA512 24ecadfccdf785bfbf27d5007afd2a4d5868493b2c5f48d6cf07c335bfbfef5cba4f12a639971e5f95877ae3b8c7b7fc0c210e404d21036af553de82a5059037
+DIST llvm-project-21eeca3db0341fef4ab4a6464ffe38b2eba5810c.tar.gz 229546432 BLAKE2B e783f08b93498b252741a07fd3aa3383ca93f66688f9bbdb2e11185c660dfff1020ab4a1ca803ab69ab28dc2fd8b5c3855f45c0b77851b8e6edeb0dc5bf6cbd4 SHA512 54420956b36f3bccabea2171a4103ca20d6b136e1d1f7f217e0ec735be4542bbd840ef228c55f3e9103ad2f9fb41393e611d5aaa1521d01fdd163b770b80ba0b

llvm-runtimes/flang-rt/flang-rt-21.0.0_pre20250329.ebuild

@@ -0,0 +1,72 @@
+# Copyright 1999-2025 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+inherit cmake flag-o-matic llvm.org
+
+DESCRIPTION="LLVM's Fortran runtime"
+HOMEPAGE="https://flang.llvm.org/"
+
+LICENSE="Apache-2.0-with-LLVM-exceptions"
+SLOT="${LLVM_MAJOR}"
+IUSE="+debug test"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+	!<llvm-core/flang-21.0.0_pre20250221-r1
+"
+BDEPEND="
+	llvm-core/llvm:${LLVM_MAJOR}
+	llvm-core/flang
+	test? (
+		dev-python/lit
+	)
+"
+
+LLVM_COMPONENTS=(
+	runtimes flang-rt cmake flang llvm/{cmake,utils/llvm-lit}
+)
+llvm.org_set_globals
+
+src_configure() {
+	# the code is not portable
+	local -x FC=flang F77=flang
+	strip-unsupported-flags
+
+	local mycmakeargs=(
+		# we may not have a runtime yet
+		-DCMAKE_Fortran_COMPILER_WORKS=TRUE
+
+		-DLLVM_ENABLE_RUNTIMES="flang-rt"
+		# this package forces NO_DEFAULT_PATHS
+		-DLLVM_BINARY_DIR="${ESYSROOT}/usr/lib/llvm/${LLVM_MAJOR}"
+
+		-DFLANG_RT_INCLUDE_TESTS=$(usex test)
+	)
+	use test && mycmakeargs+=(
+		-DLLVM_EXTERNAL_LIT="${EPREFIX}/usr/bin/lit"
+		-DLLVM_LIT_ARGS="$(get_lit_flags)"
+	)
+
+	# LLVM_ENABLE_ASSERTIONS=NO does not guarantee this for us, #614844
+	use debug || local -x CPPFLAGS="${CPPFLAGS} -DNDEBUG"
+	cmake_src_configure
+}
+
+src_test() {
+	# respect TMPDIR!
+	local -x LIT_PRESERVES_TMP=1
+	cmake_build check-flang-rt
+}
+
+src_install() {
+	cmake_src_install
+
+	# in standalone build, the library is installed to (incorrect) resource dir
+	# but the driver only looks for it in lib (sigh)
+	# https://github.com/llvm/llvm-project/issues/127538
+	mkdir -p "${ED}/usr/lib/llvm/${LLVM_MAJOR}" || die
+	mv "${ED}/usr/$(get_libdir)/clang/${LLVM_MAJOR}/lib"/* \
+		"${ED}/usr/lib/llvm/${LLVM_MAJOR}/lib" || die
+}