gentoo auto-resync : 06:02:2025 - 00:10:59

3 files changed, 764 insertions, 0 deletions

diff --git a/dev-lang/rust/Manifest b/dev-lang/rust/Manifest
index 9da5db1521fd..39d618e7d56e 100644
--- a/dev-lang/rust/Manifest
+++ b/dev-lang/rust/Manifest
@@ -17,6 +17,7 @@ AUX 1.82.0-dwarf-llvm-assertion.patch 10589 BLAKE2B 2fe6a9e5cb4714c310539cee24c2
 AUX 1.82.0-i586-baseline.patch 1818 BLAKE2B 59f396cbcc9421ae9394d0bb51053dc9addb8ca895ea8c4d7633b56361782b65f4e7f0699dec2999f2e188b4929f9036991444187f8ef35f6fea176a01999f83 SHA512 898dbde6a2f3acbe7a50023b88d3280ae85125e2bb99d18823174b541972766cf75a3457a34a024cea7348537fa6854af6ffc975abbc19323a20de87cbf5e5fb
 AUX 1.83.0-cross-compile-libz.patch 915 BLAKE2B dbb726de09c9c957f245ecce29c597f4c9c26bae0c14901c62ad51349f02d47c69fa687bd926f7ecf47aaab4ac5aac9378dfe7fa0a66dee95ff1765c5aa9b0cc SHA512 b9127b7656b8e5f79db3157d9425f97af0634088fad512e572357797a2f24f9e9c3635e06ab2efc5ad8edf86ffcab53adbf013e29162579642a382d0015ab54e
 AUX 1.83.0-dwarf-llvm-assertion.patch 10432 BLAKE2B 27f7c4145cf3046e7cb74071b72c5d7a4a3cfbdc97530c588f82225ecc8a76692d228804c3fb8e7f356d9e76b982d429fa369dc5f4607d8ad91e3a486c7cd5fd SHA512 aa0b4022f00fe126953d7d9bb6759c5ef1b6deaf7dd387e031e74c9d1cbcd6861c673afefdca5f494015ddcb64f23297f1176f22d4f3b63ec3dbd0c39527adfd
+AUX 1.84.1-fix-cross.patch 1406 BLAKE2B 3af3e4d4c52c37a4580f1ec56d2b79f2751ad017fce4e5d615e74a495acdb7a6be2e0d1e8cb6bd6c2d30a1b739444a11e20e8fd4eb002cc2c1f17ac1167e5a04 SHA512 4dd606ed7a7d026f6209fb8e7507afee04dbc3be5956ef338fc1810385e9ead568f985cac63c8d1582c16153b597a46ec97cfbf677472e4ae28e7159243a5079
 DIST rustc-1.71.1-src.tar.xz 151983068 BLAKE2B 3dfdbc246feb84a79ae94c2de978c5585ee06cf6b683d2245869b62e28f7c79f89cc589f5431537713bf088236a0b824acefc1b68e418e9eb72e1eea98054e3f SHA512 fd0e5a16bdbeb539184513583089e55f681cb772810df357b6b1464853f7022ac02edab3dd155b2262ed0047e2a25dea3808dd078dcdfce9d399384465009db4
 DIST rustc-1.71.1-src.tar.xz.asc 801 BLAKE2B a88c073a70552d73e2d7695eceabdaa478f34501b7271fabf7f4a09f3efa545181f34353e45776b05918e6aeba88adb02f9731454f7085a7abf1602fc6589983 SHA512 9dd0406cf22f1daa7fcfd015fc1c6f8d36586aa99bf14c1491ee464c1f892ab759feb83e8b55b64713170fb777fdbe038fb5fd01a59c911b6599223baaba0677
 DIST rustc-1.74.1-src.tar.xz 155968724 BLAKE2B e05f2379ac94b286f85791a138e1928e5b5b5a7749f0981d82c40c2a12860f55bf96bb2f0e924e35a0f8b2447b13052d38adea909aaa3199105787bb5a4861b3 SHA512 14c7e7ed2f38ab60299d8c7d41d78f042b6b57ef822d577b5138e60bdde31cf141eccd4332a25bc5da3d58eb5313d63c1448b5dfe9e11b8055bb8ea133a9038d
@@ -41,6 +42,8 @@ DIST rustc-1.83.0-src.tar.xz 353808388 BLAKE2B 217c85f7351a7c57a2684da2c7c81a320
 DIST rustc-1.83.0-src.tar.xz.asc 801 BLAKE2B 3bacb43d50ebba579dc2d4f1726298a7887e303e15f039ef72b840e30d90bc2cf9cdbe4617a9ee113a2b1a48f1982e72cf30323d72cdfb9a65b5b4d734ca0024 SHA512 84b252ccaddc06cb05858ff64f582dd25823818c81b1e3a00362deeda06f09e6c36948fd316d5f0ca5e24949e6f99bb14a14dbd2af1cfbb85e679e27ab0a813c
 DIST rustc-1.84.0-src.tar.xz 354993944 BLAKE2B e4697d8a9f42484556ed490390aef535b2214ccb3715ade57936211c1c637737da5f2b9a6c53a30df0fba1744fbd80d4d1382c0b74f6b36b36098bf187557201 SHA512 9e964c1b964e74083a9002fa04b072fa8fe7a520b24ad55e88a89bb2a2a2cd5727c5438d6db425b824ae7502ab215c2dd3f49777efd65f76bae09965df2e070a
 DIST rustc-1.84.0-src.tar.xz.asc 801 BLAKE2B b1846702f36b92c479499f5eb704ce1e272131fc1b6b625c8d64c873a82ed79b1de8cceb1f21ae4b9dccf81e258547debf367b7b769ac94ed10a59dee18f79f1 SHA512 5ada0e0fed9901044eaa0d7cb657f685c7e183e91245714abe4a0a8bf3062a7de281932c7de7587220df0542511f6011d057bd8bed19d98c755eab74091cdfdb
+DIST rustc-1.84.1-src.tar.xz 355078168 BLAKE2B 849e8c909493bf76ce9749b9dcb1967180223b91a41d690bc477e78557d4e24949c9a8d8276d824af8c54ad62bc4a998e7a8efbc0bbd2008a4f64f51a7690d48 SHA512 f1cc4765736551508408126e44086988e8ddc30c1a929bf7b61c6be85ad0d65928dd5fb1041cfaeee8eb37d2208f2c1917e276aef2bc9a8e40e34f6713b349e1
+DIST rustc-1.84.1-src.tar.xz.asc 801 BLAKE2B f3decd3470fd1eff33adbb376490a30eb8db28dd4176bde0fefe4f60acf79c3dd0e1a330d519b5319360136ea7d0a124f6720dea08617202d9e9298da992ccf6 SHA512 a241fe3efba293f3e872b74f09dd0d184e0239afd1416326d57bf1134d92721c65b187f5c99962b51671877a539f18e82d2d797c76af42615c11a8bb3905f796
 EBUILD rust-1.71.1-r100.ebuild 22077 BLAKE2B 1082eec69086f44922a4d9b4d7d0fbee5104c4653fe6320764748638389871081c5812aa0bed84ecd36f6d764e38a257c640518b3ca190797ca595506106739f SHA512 461a0bd207a4424c2512ee404202b14fdc8bf6d4bd628e38f325584ff4e452de0f3615e3a3683b2d1eae0b9498443eccb10f6800cf3c6be862f1643b9203c017
 EBUILD rust-1.74.1-r100.ebuild 37690 BLAKE2B 93ff1451143f5282ef231911a3b820649052300b933a9e6fd602ce6dcbf6f88af118e2835e59d3b520ba7f09a292d71d1f9b7b7a48bbbeadaaf880ff0a0dc3ea SHA512 2709d8377472eda62ebd2d0c296b1b678c106e6cc33268823391f0e2072f06551e1bb9094017077f4bd56aa0a34bee3a329d0a6f27fd1f8304af6abcc9e9b241
 EBUILD rust-1.75.0-r100.ebuild 23584 BLAKE2B ec9b5d0dc286ce5f1931df6e60817531f3ce6002a3916e47355c557693b19bdacdefd3e01d309880c8e48e53d4fc9082bab4aa2ed9da34c51df8b8c25e60305f SHA512 f759a9db473a3d19571b20669b9631446b71c508ba9cf42edc126e1da03ce8ad34478b6712f48711ee152001841d31662ea6f227faacec1fb51b625522415e64
@@ -54,4 +57,5 @@ EBUILD rust-1.82.0-r100.ebuild 23997 BLAKE2B 227d902466e31d42551be544e88839814ff
 EBUILD rust-1.82.0-r101.ebuild 24046 BLAKE2B d132b0109d9d1e68ded0357221609102f0e638069e4ec2bf61e53fb94b388fe67e97b5cb5ee3f29ecdc3a9f4c18a4ad6cef0e08addc248289ae3178c2e04aa04 SHA512 31f3e5bfa8345bcad487474bd8e0570c31e51a7e477d030f2fe61148e4598f069211139504a43958367b740cf38b18ff92e46e49d6080b7df8177453e9dae14e
 EBUILD rust-1.83.0-r1.ebuild 23279 BLAKE2B 183f2a6f686030c2efad110709d52b68c655dc374faa748f83c5d33ced7e44b81d5c321e843e8ffcd6c4d248bb8b6452986eb9f1e0b636e199404668f3a54518 SHA512 8220054d98db8bb50d9abd765ffefaafd360ad13ee566485e2f82930a8821b32c7b5e33080127e8fea5dbe655a81c8edd1563d0efa5c78be4c41d8bd4af22050
 EBUILD rust-1.84.0.ebuild 22990 BLAKE2B cecc312f026169d94fdd5d435c54fe83f75bc5c6c0d3954b255d4a20dcca2a97254a7555e2c64c7961643bce0cb2779fc105cc0bf3dc6f4c1c3c3ce6f4736213 SHA512 c31e9762a00f862814865b70d7ec2ea1fe26aa7ea0c97f8795e29dc1a97e74c46d2f8381da47e11b389c112312421ee059134a29b3924a476b526ff49bf94d1c
+EBUILD rust-1.84.1.ebuild 22975 BLAKE2B c15b5c751ce0190fbc1954e9729670b1ac22d8debf5b4c5afd574f7e4066b4278b4e0439bd957859fdc955e4e0aca1a4957aa35054de627f6618bff0fd99c771 SHA512 e2dff3275242878eabe607ff4f493ef9760869fc75f7950cd2941ed4f718b703ba8bba33018aca5544bf88a87fd0b346e7dd52756a911fba3a0a033ccc181145
 MISC metadata.xml 1841 BLAKE2B 48a8167ae44a7f4892b917895298627ac920af6c488180980e65bdeec53b650455fc6d7dddad0a7a8257d473080082377fb6b6df6a834b294b6e6485e6784a1e SHA512 1f5fd792b65ccac89a61233004980d9f7cbaecea5d05f35f9cc2dc9cab4e3ccfcd46828e88770a1b8ba5ca23064b6a75eea72a0b32bcce52bb399b85ac95f755
diff --git a/dev-lang/rust/files/1.84.1-fix-cross.patch b/dev-lang/rust/files/1.84.1-fix-cross.patch
new file mode 100644
index 000000000000..47d7766ae951
--- /dev/null
+++ b/dev-lang/rust/files/1.84.1-fix-cross.patch
@@ -0,0 +1,30 @@
+https://github.com/rust-lang/rust/issues/133629
+https://github.com/rust-lang/rust/commit/a24d859f19bbefe5371694f318568b0ab5a13299
+
+From: onur-ozkan <work@onurozkan.dev>
+Date: Thu, 30 Jan 2025 16:51:08 +0000
+Subject: [PATCH] set rustc dylib on manually constructed rustc command
+
+Signed-off-by: onur-ozkan <work@onurozkan.dev>
+--- a/src/bootstrap/src/core/builder/cargo.rs
++++ b/src/bootstrap/src/core/builder/cargo.rs
+@@ -653,7 +653,10 @@ impl Builder<'_> {
+                 // Build proc macros both for the host and the target unless proc-macros are not
+                 // supported by the target.
+                 if target != compiler.host && cmd_kind != Kind::Check {
+-                    let error = command(self.rustc(compiler))
++                    let mut rustc_cmd = command(self.rustc(compiler));
++                    self.add_rustc_lib_path(compiler, &mut rustc_cmd);
++
++                    let error = rustc_cmd
+                         .arg("--target")
+                         .arg(target.rustc_target_arg())
+                         .arg("--print=file-names")
+@@ -661,6 +664,7 @@ impl Builder<'_> {
+                         .arg("-")
+                         .run_capture(self)
+                         .stderr();
++
+                     let not_supported = error
+                         .lines()
+                         .any(|line| line.contains("unsupported crate type `proc-macro`"));
diff --git a/dev-lang/rust/rust-1.84.1.ebuild b/dev-lang/rust/rust-1.84.1.ebuild
new file mode 100644
index 000000000000..7f9acdb9a801
--- /dev/null
+++ b/dev-lang/rust/rust-1.84.1.ebuild
@@ -0,0 +1,730 @@
+# Copyright 1999-2025 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+LLVM_COMPAT=( 19 )
+PYTHON_COMPAT=( python3_{10..13} )
+
+RUST_MAX_VER=${PV}
+RUST_MIN_VER="$(ver_cut 1).$(($(ver_cut 2) - 1)).0"
+
+inherit check-reqs estack flag-o-matic llvm-r1 multiprocessing optfeature \
+	multilib multilib-build python-any-r1 rust rust-toolchain toolchain-funcs verify-sig
+
+if [[ ${PV} = *beta* ]]; then
+	betaver=${PV//*beta}
+	BETA_SNAPSHOT="${betaver:0:4}-${betaver:4:2}-${betaver:6:2}"
+	MY_P="rustc-beta"
+	SRC="${BETA_SNAPSHOT}/rustc-beta-src.tar.xz -> rustc-${PV}-src.tar.xz"
+else
+	MY_P="rustc-${PV}"
+	SRC="${MY_P}-src.tar.xz"
+	KEYWORDS="~amd64 ~arm ~arm64 ~loong ~mips ~ppc ~ppc64 ~riscv ~sparc ~x86"
+fi
+
+DESCRIPTION="Systems programming language from Mozilla"
+HOMEPAGE="https://www.rust-lang.org/"
+
+SRC_URI="
+	https://static.rust-lang.org/dist/${SRC}
+	verify-sig? ( https://static.rust-lang.org/dist/${SRC}.asc )
+"
+S="${WORKDIR}/${MY_P}-src"
+
+# keep in sync with llvm ebuild of the same version as bundled one.
+ALL_LLVM_TARGETS=( AArch64 AMDGPU ARC ARM AVR BPF CSKY DirectX Hexagon Lanai
+	LoongArch M68k Mips MSP430 NVPTX PowerPC RISCV Sparc SPIRV SystemZ VE
+	WebAssembly X86 XCore Xtensa )
+ALL_LLVM_TARGETS=( "${ALL_LLVM_TARGETS[@]/#/llvm_targets_}" )
+LLVM_TARGET_USEDEPS=${ALL_LLVM_TARGETS[@]/%/(-)?}
+
+LICENSE="|| ( MIT Apache-2.0 ) BSD BSD-1 BSD-2 BSD-4"
+SLOT="${PV}"
+
+IUSE="big-endian clippy cpu_flags_x86_sse2 debug dist doc llvm-libunwind lto miri nightly parallel-compiler rustfmt rust-analyzer rust-src system-llvm test wasm ${ALL_LLVM_TARGETS[*]}"
+
+LLVM_DEPEND=()
+# splitting usedeps needed to avoid CI/pkgcheck's UncheckableDep limitation
+for _x in "${ALL_LLVM_TARGETS[@]}"; do
+	LLVM_DEPEND+=( "	${_x}? ( $(llvm_gen_dep "llvm-core/llvm:\${LLVM_SLOT}[${_x}]") )" )
+done
+LLVM_DEPEND+=( "	wasm? ( $(llvm_gen_dep 'llvm-core/lld:${LLVM_SLOT}') )" )
+LLVM_DEPEND+=( "	$(llvm_gen_dep 'llvm-core/llvm:${LLVM_SLOT}')" )
+
+BDEPEND="${PYTHON_DEPS}
+	app-eselect/eselect-rust
+	|| (
+		>=sys-devel/gcc-4.7
+		>=llvm-core/clang-3.5
+	)
+	!system-llvm? (
+		>=dev-build/cmake-3.13.4
+		app-alternatives/ninja
+	)
+	test? ( dev-debug/gdb )
+	verify-sig? ( sec-keys/openpgp-keys-rust )
+"
+
+DEPEND="
+	>=app-arch/xz-utils-5.2
+	net-misc/curl:=[http2,ssl]
+	sys-libs/zlib:=
+	dev-libs/openssl:0=
+	system-llvm? (
+		${LLVM_DEPEND[*]}
+		llvm-libunwind? ( llvm-runtimes/libunwind:= )
+	)
+	!system-llvm? (
+		!llvm-libunwind? (
+			elibc_musl? ( sys-libs/libunwind:= )
+		)
+	)
+"
+
+RDEPEND="${DEPEND}
+	app-eselect/eselect-rust
+	dev-lang/rust-common
+	sys-apps/lsb-release
+	!dev-lang/rust:stable
+	!dev-lang/rust-bin:stable
+"
+
+REQUIRED_USE="|| ( ${ALL_LLVM_TARGETS[*]} )
+	miri? ( nightly )
+	parallel-compiler? ( nightly )
+	rust-analyzer? ( rust-src )
+	test? ( ${ALL_LLVM_TARGETS[*]} )
+	wasm? ( llvm_targets_WebAssembly )
+	x86? ( cpu_flags_x86_sse2 )
+"
+
+# we don't use cmake.eclass, but can get a warning
+CMAKE_WARN_UNUSED_CLI=no
+
+QA_FLAGS_IGNORED="
+	usr/lib/${PN}/${PV}/bin/.*
+	usr/lib/${PN}/${PV}/libexec/.*
+	usr/lib/${PN}/${PV}/lib/lib.*.so
+	usr/lib/${PN}/${PV}/lib/rustlib/.*/bin/.*
+	usr/lib/${PN}/${PV}/lib/rustlib/.*/lib/lib.*.so
+"
+
+QA_SONAME="
+	usr/lib/${PN}/${PV}/lib/lib.*.so.*
+	usr/lib/${PN}/${PV}/lib/rustlib/.*/lib/lib.*.so
+"
+
+QA_PRESTRIPPED="
+	usr/lib/${PN}/${PV}/lib/rustlib/.*/bin/rust-llvm-dwp
+	usr/lib/${PN}/${PV}/lib/rustlib/.*/lib/self-contained/crtn.o
+"
+
+# An rmeta file is custom binary format that contains the metadata for the crate.
+# rmeta files do not support linking, since they do not contain compiled object files.
+# so we can safely silence the warning for this QA check.
+QA_EXECSTACK="usr/lib/${PN}/${PV}/lib/rustlib/*/lib*.rlib:lib.rmeta"
+
+# causes double bootstrap
+RESTRICT="test"
+
+VERIFY_SIG_OPENPGP_KEY_PATH=/usr/share/openpgp-keys/rust.asc
+
+PATCHES=(
+	"${FILESDIR}"/1.78.0-musl-dynamic-linking.patch
+	"${FILESDIR}"/1.83.0-cross-compile-libz.patch
+	"${FILESDIR}"/1.67.0-doc-wasm.patch
+	"${FILESDIR}"/1.84.1-fix-cross.patch # already upstreamed
+)
+
+clear_vendor_checksums() {
+	sed -i 's/\("files":{\)[^}]*/\1/' "vendor/${1}/.cargo-checksum.json" || die
+}
+
+toml_usex() {
+	usex "${1}" true false
+}
+
+pre_build_checks() {
+	local M=9216
+	# multiply requirements by 1.3 if we are doing x86-multilib
+	if use amd64; then
+		M=$(( $(usex abi_x86_32 13 10) * ${M} / 10 ))
+	fi
+	M=$(( $(usex clippy 128 0) + ${M} ))
+	M=$(( $(usex miri 128 0) + ${M} ))
+	M=$(( $(usex rustfmt 256 0) + ${M} ))
+	# add 2G if we compile llvm and 256M per llvm_target
+	if ! use system-llvm; then
+		M=$(( 2048 + ${M} ))
+		local ltarget
+		for ltarget in ${ALL_LLVM_TARGETS[@]}; do
+			M=$(( $(usex ${ltarget} 256 0) + ${M} ))
+		done
+	fi
+	M=$(( $(usex wasm 256 0) + ${M} ))
+	M=$(( $(usex debug 2 1) * ${M} ))
+	eshopts_push -s extglob
+	if is-flagq '-g?(gdb)?([1-9])'; then
+		M=$(( 15 * ${M} / 10 ))
+	fi
+	eshopts_pop
+	M=$(( $(usex doc 256 0) + ${M} ))
+	CHECKREQS_DISK_BUILD=${M}M check-reqs_pkg_${EBUILD_PHASE}
+}
+
+llvm_check_deps() {
+	has_version -r "llvm-core/llvm:${LLVM_SLOT}[${LLVM_TARGET_USEDEPS// /,}]"
+}
+
+# Is LLVM being linked against libc++?
+is_libcxx_linked() {
+	local code='#include <ciso646>
+#if defined(_LIBCPP_VERSION)
+	HAVE_LIBCXX
+#endif
+'
+	local out=$($(tc-getCXX) ${CXXFLAGS} ${CPPFLAGS} -x c++ -E -P - <<<"${code}") || return 1
+	[[ ${out} == *HAVE_LIBCXX* ]]
+}
+
+pkg_pretend() {
+	pre_build_checks
+}
+
+pkg_setup() {
+	pre_build_checks
+	python-any-r1_pkg_setup
+
+	export LIBGIT2_NO_PKG_CONFIG=1 #749381
+	if tc-is-cross-compiler; then
+		use system-llvm && die "USE=system-llvm not allowed when cross-compiling"
+		local cross_llvm_target="$(llvm_tuple_to_target "${CBUILD}")"
+		use "llvm_targets_${cross_llvm_target}" || \
+			die "Must enable LLVM_TARGETS=${cross_llvm_target} matching CBUILD=${CBUILD} when cross-compiling"
+	fi
+
+	rust_pkg_setup
+
+	if use system-llvm; then
+		llvm-r1_pkg_setup
+
+		local llvm_config="$(get_llvm_prefix)/bin/llvm-config"
+		export LLVM_LINK_SHARED=1
+		export RUSTFLAGS="${RUSTFLAGS} -Lnative=$("${llvm_config}" --libdir)"
+	fi
+}
+
+src_prepare() {
+	# Rust baselines to Pentium4 on x86, this patch lowers the baseline to i586 when sse2 is not set.
+	if use x86; then
+		if ! use cpu_flags_x86_sse2; then
+			eapply "${FILESDIR}/1.82.0-i586-baseline.patch"
+			#grep -rl cmd.args.push\(\"-march=i686\" . | xargs sed  -i 's/march=i686/-march=i586/g' || die
+		fi
+	fi
+
+	default
+}
+
+src_configure() {
+	if tc-is-cross-compiler; then
+		export PKG_CONFIG_ALLOW_CROSS=1
+		export PKG_CONFIG_PATH="${ESYSROOT}/usr/$(get_libdir)/pkgconfig"
+		export OPENSSL_INCLUDE_DIR="${ESYSROOT}/usr/include"
+		export OPENSSL_LIB_DIR="${ESYSROOT}/usr/$(get_libdir)"
+	fi
+
+	filter-lto # https://bugs.gentoo.org/862109 https://bugs.gentoo.org/866231
+
+	local rust_target="" rust_targets="" arch_cflags
+
+	# Collect rust target names to compile standard libs for all ABIs.
+	for v in $(multilib_get_enabled_abi_pairs); do
+		rust_targets+=",\"$(rust_abi $(get_abi_CHOST ${v##*.}))\""
+	done
+	if use wasm; then
+		rust_targets+=",\"wasm32-unknown-unknown\""
+		if use system-llvm; then
+			# un-hardcode rust-lld linker for this target
+			# https://bugs.gentoo.org/715348
+			sed -i '/linker:/ s/rust-lld/wasm-ld/' compiler/rustc_target/src/spec/base/wasm.rs || die
+		fi
+	fi
+	rust_targets="${rust_targets#,}"
+
+	# cargo and rustdoc are mandatory and should always be included
+	local tools='"cargo","rustdoc"'
+	use clippy && tools+=',"clippy"'
+	use miri && tools+=',"miri"'
+	use rustfmt && tools+=',"rustfmt"'
+	use rust-analyzer && tools+=',"rust-analyzer","rust-analyzer-proc-macro-srv"'
+	use rust-src && tools+=',"src"'
+
+	local rust_stage0_root="$(${RUSTC} --print sysroot || die "Can't determine rust's sysroot")"
+	# in case of prefix it will be already prefixed, as --print sysroot returns full path
+	[[ -d ${rust_stage0_root} ]] || die "${rust_stage0_root} is not a directory"
+
+	rust_target="$(rust_abi)"
+	rust_build="$(rust_abi "${CBUILD}")"
+	rust_host="$(rust_abi "${CHOST}")"
+
+	local cm_btype="$(usex debug DEBUG RELEASE)"
+	cat <<- _EOF_ > "${S}"/config.toml
+		# https://github.com/rust-lang/rust/issues/135358 (bug #947897)
+		profile = "dist"
+		[llvm]
+		download-ci-llvm = false
+		optimize = $(toml_usex !debug)
+		release-debuginfo = $(toml_usex debug)
+		assertions = $(toml_usex debug)
+		ninja = true
+		targets = "${LLVM_TARGETS// /;}"
+		experimental-targets = ""
+		link-shared = $(toml_usex system-llvm)
+		$(if is_libcxx_linked; then
+			# https://bugs.gentoo.org/732632
+			echo "use-libcxx = true"
+			echo "static-libstdcpp = false"
+		fi)
+		$(case "${rust_target}" in
+			i586-*-linux-*)
+				# https://github.com/rust-lang/rust/issues/93059
+				echo 'cflags = "-fcf-protection=none"'
+				echo 'cxxflags = "-fcf-protection=none"'
+				echo 'ldflags = "-fcf-protection=none"'
+				;;
+			*)
+				;;
+		esac)
+		enable-warnings = false
+		[llvm.build-config]
+		CMAKE_VERBOSE_MAKEFILE = "ON"
+		$(if ! tc-is-cross-compiler; then
+			# When cross-compiling, LLVM is compiled twice, once for host and
+			# once for target.  Unfortunately, this build configuration applies
+			# to both, which means any flags applicable to one target but not
+			# the other will break.  Conditionally disable respecting user
+			# flags when cross-compiling.
+			echo "CMAKE_C_FLAGS_${cm_btype} = \"${CFLAGS}\""
+			echo "CMAKE_CXX_FLAGS_${cm_btype} = \"${CXXFLAGS}\""
+			echo "CMAKE_EXE_LINKER_FLAGS_${cm_btype} = \"${LDFLAGS}\""
+			echo "CMAKE_MODULE_LINKER_FLAGS_${cm_btype} = \"${LDFLAGS}\""
+			echo "CMAKE_SHARED_LINKER_FLAGS_${cm_btype} = \"${LDFLAGS}\""
+			echo "CMAKE_STATIC_LINKER_FLAGS_${cm_btype} = \"${ARFLAGS}\""
+		fi)
+		[build]
+		build-stage = 2
+		test-stage = 2
+		build = "${rust_build}"
+		host = ["${rust_host}"]
+		target = [${rust_targets}]
+		cargo = "${rust_stage0_root}/bin/cargo"
+		rustc = "${rust_stage0_root}/bin/rustc"
+		rustfmt = "${rust_stage0_root}/bin/rustfmt"
+		docs = $(toml_usex doc)
+		compiler-docs = false
+		submodules = false
+		python = "${EPYTHON}"
+		locked-deps = true
+		vendor = true
+		extended = true
+		tools = [${tools}]
+		verbose = 2
+		sanitizers = false
+		profiler = true
+		cargo-native-static = false
+		[install]
+		prefix = "${EPREFIX}/usr/lib/${PN}/${PV}"
+		sysconfdir = "etc"
+		docdir = "share/doc/rust"
+		bindir = "bin"
+		libdir = "lib"
+		mandir = "share/man"
+		[rust]
+		# https://github.com/rust-lang/rust/issues/54872
+		codegen-units-std = 1
+		optimize = true
+		debug = $(toml_usex debug)
+		debug-assertions = $(toml_usex debug)
+		debug-assertions-std = $(toml_usex debug)
+		debuginfo-level = $(usex debug 2 0)
+		debuginfo-level-rustc = $(usex debug 2 0)
+		debuginfo-level-std = $(usex debug 2 0)
+		debuginfo-level-tools = $(usex debug 2 0)
+		debuginfo-level-tests = 0
+		backtrace = true
+		incremental = false
+		$(if ! tc-is-cross-compiler; then
+			echo "default-linker = \"$(tc-getCC)\""
+		fi)
+		parallel-compiler = $(toml_usex parallel-compiler)
+		channel = "$(usex nightly nightly stable)"
+		description = "gentoo"
+		rpath = false
+		verbose-tests = true
+		optimize-tests = $(toml_usex !debug)
+		codegen-tests = true
+		dist-src = false
+		remap-debuginfo = true
+		lld = $(usex system-llvm false $(toml_usex wasm))
+		# only deny warnings if doc+wasm are NOT requested, documenting stage0 wasm std fails without it
+		# https://github.com/rust-lang/rust/issues/74976
+		# https://github.com/rust-lang/rust/issues/76526
+		deny-warnings = $(usex wasm $(usex doc false true) true)
+		backtrace-on-ice = true
+		jemalloc = false
+		# See https://github.com/rust-lang/rust/issues/121124
+		lto = "$(usex lto thin off)"
+		[dist]
+		src-tarball = false
+		compression-formats = ["xz"]
+		compression-profile = "balanced"
+	_EOF_
+
+	for v in $(multilib_get_enabled_abi_pairs); do
+		rust_target=$(rust_abi $(get_abi_CHOST ${v##*.}))
+		arch_cflags="$(get_abi_CFLAGS ${v##*.})"
+
+		export CFLAGS_${rust_target//-/_}="${arch_cflags}"
+
+		cat <<- _EOF_ >> "${S}"/config.toml
+			[target.${rust_target}]
+			ar = "$(tc-getAR)"
+			cc = "$(tc-getCC)"
+			cxx = "$(tc-getCXX)"
+			linker = "$(tc-getCC)"
+			ranlib = "$(tc-getRANLIB)"
+			llvm-libunwind = "$(usex llvm-libunwind $(usex system-llvm system in-tree) no)"
+		_EOF_
+		if use system-llvm; then
+			cat <<- _EOF_ >> "${S}"/config.toml
+				llvm-config = "$(get_llvm_prefix)/bin/llvm-config"
+			_EOF_
+		fi
+		# by default librustc_target/spec/linux_musl_base.rs sets base.crt_static_default = true;
+		# but we patch it and set to false here as well
+		if use elibc_musl; then
+			cat <<- _EOF_ >> "${S}"/config.toml
+				crt-static = false
+				musl-root = "$($(tc-getCC) -print-sysroot)/usr"
+			_EOF_
+		fi
+	done
+	if use wasm; then
+		wasm_target="wasm32-unknown-unknown"
+		export CFLAGS_${wasm_target//-/_}="$(filter-flags '-mcpu*' '-march*' '-mtune*'; echo "$CFLAGS")"
+		cat <<- _EOF_ >> "${S}"/config.toml
+			[target.wasm32-unknown-unknown]
+			linker = "$(usex system-llvm lld rust-lld)"
+			# wasm target does not have profiler_builtins https://bugs.gentoo.org/848483
+			profiler = false
+		_EOF_
+	fi
+
+	if [[ -n ${I_KNOW_WHAT_I_AM_DOING_CROSS} ]]; then # whitespace intentionally shifted below
+	# experimental cross support
+	# discussion: https://bugs.gentoo.org/679878
+	# TODO: c*flags, clang, system-llvm, cargo.eclass target support
+	# it would be much better if we could split out stdlib
+	# complilation to separate ebuild and abuse CATEGORY to
+	# just install to /usr/lib/rustlib/<target>
+
+	# extra targets defined as a bash array
+	# spec format:  <LLVM target>:<rust-target>:<CTARGET>
+	# best place would be /etc/portage/env/dev-lang/rust
+	# Example:
+	# RUST_CROSS_TARGETS=(
+	#	"AArch64:aarch64-unknown-linux-gnu:aarch64-unknown-linux-gnu"
+	# )
+	# no extra hand holding is done, no target transformations, all
+	# values are passed as-is with just basic checks, so it's up to user to supply correct values
+	# valid rust targets can be obtained with
+	# 	rustc --print target-list
+	# matching cross toolchain has to be installed
+	# matching LLVM_TARGET has to be enabled for both rust and llvm (if using system one)
+	# only gcc toolchains installed with crossdev are checked for now.
+
+	# BUG: we can't pass host flags to cross compiler, so just filter for now
+	# BUG: this should be more fine-grained.
+	filter-flags '-mcpu=*' '-march=*' '-mtune=*'
+
+	local cross_target_spec
+	for cross_target_spec in "${RUST_CROSS_TARGETS[@]}";do
+		# extracts first element form <LLVM target>:<rust-target>:<CTARGET>
+		local cross_llvm_target="${cross_target_spec%%:*}"
+		# extracts toolchain triples, <rust-target>:<CTARGET>
+		local cross_triples="${cross_target_spec#*:}"
+		# extracts first element after before : separator
+		local cross_rust_target="${cross_triples%%:*}"
+		# extracts last element after : separator
+		local cross_toolchain="${cross_triples##*:}"
+		use llvm_targets_${cross_llvm_target} || die "need llvm_targets_${cross_llvm_target} target enabled"
+		command -v ${cross_toolchain}-gcc > /dev/null 2>&1 || die "need ${cross_toolchain} cross toolchain"
+
+		cat <<- _EOF_ >> "${S}"/config.toml
+			[target.${cross_rust_target}]
+			ar = "${cross_toolchain}-ar"
+			cc = "${cross_toolchain}-gcc"
+			cxx = "${cross_toolchain}-g++"
+			linker = "${cross_toolchain}-gcc"
+			ranlib = "${cross_toolchain}-ranlib"
+		_EOF_
+		if use system-llvm; then
+			cat <<- _EOF_ >> "${S}"/config.toml
+				llvm-config = "$(get_llvm_prefix)/bin/llvm-config"
+			_EOF_
+		fi
+		if [[ "${cross_toolchain}" == *-musl* ]]; then
+			cat <<- _EOF_ >> "${S}"/config.toml
+				musl-root = "$(${cross_toolchain}-gcc -print-sysroot)/usr"
+			_EOF_
+		fi
+
+		# append cross target to "normal" target list
+		# example 'target = ["powerpc64le-unknown-linux-gnu"]'
+		# becomes 'target = ["powerpc64le-unknown-linux-gnu","aarch64-unknown-linux-gnu"]'
+
+		rust_targets="${rust_targets},\"${cross_rust_target}\""
+		sed -i "/^target = \[/ s#\[.*\]#\[${rust_targets}\]#" config.toml || die
+
+		ewarn
+		ewarn "Enabled ${cross_rust_target} rust target"
+		ewarn "Using ${cross_toolchain} cross toolchain"
+		ewarn
+		if ! has_version -b 'sys-devel/binutils[multitarget]' ; then
+			ewarn "'sys-devel/binutils[multitarget]' is not installed"
+			ewarn "'strip' will be unable to strip cross libraries"
+			ewarn "cross targets will be installed with full debug information"
+			ewarn "enable 'multitarget' USE flag for binutils to be able to strip object files"
+			ewarn
+			ewarn "Alternatively llvm-strip can be used, it supports stripping any target"
+			ewarn "define STRIP=\"llvm-strip\" to use it (experimental)"
+			ewarn
+		fi
+	done
+	fi # I_KNOW_WHAT_I_AM_DOING_CROSS
+
+	einfo "Rust configured with the following flags:"
+	echo
+	echo RUSTFLAGS="\"${RUSTFLAGS}\""
+	echo RUSTFLAGS_BOOTSTRAP="\"${RUSTFLAGS_BOOTSTRAP}\""
+	echo RUSTFLAGS_NOT_BOOTSTRAP="\"${RUSTFLAGS_NOT_BOOTSTRAP}\""
+	echo MAGIC_EXTRA_RUSTFLAGS="\"${MAGIC_EXTRA_RUSTFLAGS}\""
+	env | grep "CARGO_TARGET_.*_RUSTFLAGS="
+	env | grep "CFLAGS_.*"
+	echo
+	einfo "config.toml contents:"
+	cat "${S}"/config.toml || die
+	echo
+}
+
+src_compile() {
+	RUST_BACKTRACE=1 "${EPYTHON}" ./x.py build -vvv --config="${S}"/config.toml -j$(makeopts_jobs) || die
+}
+
+src_test() {
+	# https://rustc-dev-guide.rust-lang.org/tests/intro.html
+
+	# those are basic and codegen tests.
+	local tests=(
+		codegen
+		codegen-units
+		compile-fail
+		incremental
+		mir-opt
+		pretty
+		run-make
+	)
+
+	# fails if llvm is not built with ALL targets.
+	# and known to fail with system llvm sometimes.
+	use system-llvm || tests+=( assembly )
+
+	# fragile/expensive/less important tests
+	# or tests that require extra builds
+	# TODO: instead of skipping, just make some nonfatal.
+	if [[ ${ERUST_RUN_EXTRA_TESTS:-no} != no ]]; then
+		tests+=(
+			rustdoc
+			rustdoc-js
+			rustdoc-js-std
+			rustdoc-ui
+			run-make-fulldeps
+			ui
+			ui-fulldeps
+		)
+	fi
+
+	local i failed=()
+	einfo "rust_src_test: enabled tests ${tests[@]/#/src/test/}"
+	for i in "${tests[@]}"; do
+		local t="src/test/${i}"
+		einfo "rust_src_test: running ${t}"
+		if ! RUST_BACKTRACE=1 "${EPYTHON}" ./x.py test -vv --config="${S}"/config.toml \
+				-j$(makeopts_jobs) --no-doc --no-fail-fast "${t}"
+		then
+				failed+=( "${t}" )
+				eerror "rust_src_test: ${t} failed"
+		fi
+	done
+
+	if [[ ${#failed[@]} -ne 0 ]]; then
+		eerror "rust_src_test: failure summary: ${failed[@]}"
+		die "aborting due to test failures"
+	fi
+}
+
+src_install() {
+	DESTDIR="${D}" "${EPYTHON}" ./x.py install -vv --config="${S}"/config.toml -j$(makeopts_jobs) || die
+
+	docompress /usr/lib/${PN}/${PV}/share/man/
+
+	# bug #689562, #689160
+	rm -v "${ED}/usr/lib/${PN}/${PV}/etc/bash_completion.d/cargo" || die
+	rmdir -v "${ED}/usr/lib/${PN}/${PV}"/etc{/bash_completion.d,} || die
+
+	local symlinks=(
+		cargo
+		rustc
+		rustdoc
+		rust-gdb
+		rust-gdbgui
+		rust-lldb
+	)
+
+	use clippy && symlinks+=( clippy-driver cargo-clippy )
+	use miri && symlinks+=( miri cargo-miri )
+	use rustfmt && symlinks+=( rustfmt cargo-fmt )
+	use rust-analyzer && symlinks+=( rust-analyzer )
+
+	einfo "installing eselect-rust symlinks and paths: ${symlinks[@]}"
+	local i
+	for i in "${symlinks[@]}"; do
+		# we need realpath on /usr/bin/* symlink return version-appended binary path.
+		# so /usr/bin/rustc should point to /usr/lib/rust/<ver>/bin/rustc-<ver>
+		# need to fix eselect-rust to remove this hack.
+		local ver_i="${i}-${PV}"
+		if [[ -f "${ED}/usr/lib/${PN}/${PV}/bin/${i}" ]]; then
+			einfo "Installing ${i} symlink"
+			ln -v "${ED}/usr/lib/${PN}/${PV}/bin/${i}" "${ED}/usr/lib/${PN}/${PV}/bin/${ver_i}" || die
+		else
+			ewarn "${i} symlink requested, but source file not found"
+			ewarn "please report this"
+		fi
+		dosym "../lib/${PN}/${PV}/bin/${ver_i}" "/usr/bin/${ver_i}"
+	done
+
+	# symlinks to switch components to active rust in eselect
+	dosym "${PV}/lib" "/usr/lib/${PN}/lib-${PV}"
+	use rust-analyzer && dosym "${PV}/libexec" "/usr/lib/${PN}/libexec-${PV}"
+	dosym "${PV}/share/man" "/usr/lib/${PN}/man-${PV}"
+	dosym "rust/${PV}/lib/rustlib" "/usr/lib/rustlib-${PV}"
+	dosym "../../lib/${PN}/${PV}/share/doc/rust" "/usr/share/doc/${P}"
+
+	newenvd - "50${P}" <<-_EOF_
+		LDPATH="${EPREFIX}/usr/lib/rust/lib-${PV}"
+		MANPATH="${EPREFIX}/usr/lib/rust/man-${PV}"
+	_EOF_
+
+	rm -rf "${ED}/usr/lib/${PN}/${PV}"/*.old || die
+	rm -rf "${ED}/usr/lib/${PN}/${PV}/bin"/*.old || die
+	rm -rf "${ED}/usr/lib/${PN}/${PV}/doc"/*.old || die
+
+	# note: eselect-rust adds EROOT to all paths below
+	cat <<-_EOF_ > "${T}/provider-${P}"
+		/usr/bin/cargo
+		/usr/bin/rustdoc
+		/usr/bin/rust-gdb
+		/usr/bin/rust-gdbgui
+		/usr/bin/rust-lldb
+		/usr/lib/rustlib
+		/usr/lib/rust/lib
+		/usr/lib/rust/man
+		/usr/share/doc/rust
+	_EOF_
+
+	if use clippy; then
+		echo /usr/bin/clippy-driver >> "${T}/provider-${P}"
+		echo /usr/bin/cargo-clippy >> "${T}/provider-${P}"
+	fi
+	if use miri; then
+		echo /usr/bin/miri >> "${T}/provider-${P}"
+		echo /usr/bin/cargo-miri >> "${T}/provider-${P}"
+	fi
+	if use rustfmt; then
+		echo /usr/bin/rustfmt >> "${T}/provider-${P}"
+		echo /usr/bin/cargo-fmt >> "${T}/provider-${P}"
+	fi
+	if use rust-analyzer; then
+		echo /usr/lib/rust/libexec >> "${T}/provider-${P}"
+		echo /usr/bin/rust-analyzer >> "${T}/provider-${P}"
+	fi
+
+	insinto /etc/env.d/rust
+	doins "${T}/provider-${P}"
+
+	if use dist; then
+		"${EPYTHON}" ./x.py dist -vv --config="${S}"/config.toml -j$(makeopts_jobs) || die
+		insinto "/usr/lib/${PN}/${PV}/dist"
+		doins -r "${S}/build/dist/."
+	fi
+}
+
+pkg_preinst() {
+	# 943308 and friends; basically --keep-going can forget to unmerge old rust
+	# but the soft blocker allows us to install conflicting files.
+	# This results in duplicated .{rlib,so} files which confuses rustc and results in
+	# the need for manual intervention.
+	if has_version -b "dev-lang/rust:stable/$(ver_cut 1-2)"; then
+		# we need to find all .{rlib,so} files in the old rust lib directory
+		# and store them in an array for later use
+		readarray -d '' old_rust_libs < <(
+			find "${EROOT}/usr/lib/rust/${PV}/lib/rustlib" \
+			-type f \( -name '*.rlib' -o -name '*.so' \) -print0)
+		export old_rust_libs
+		if [[ ${#old_rust_libs[@]} -gt 0 ]]; then
+			einfo "Found old .rlib and .so files in the old rust lib directory"
+		else
+			die "Found no old .rlib and .so files but old rust version is installed. Bailing!"
+		fi
+	fi
+}
+
+pkg_postinst() {
+
+	if has_version -b "dev-lang/rust:stable/$(ver_cut 1-2)"; then
+		# Be _extra_ careful here as we're removing files from the live filesystem
+		local f
+		for f in "${old_rust_libs[@]}"; do
+			[[ -f ${f} ]] || die "old_rust_libs array contains non-existent file"
+			local base_name="${f%-*}"
+			local ext="${f##*.}"
+			local matching_files=("${base_name}"-*.${ext})
+			if [[ ${#matching_files[@]} -ne 2 ]]; then
+				die "Expected exactly two files matching ${base_name}-\*.rlib, but found ${#matching_files[@]}"
+			fi
+			einfo "Removing old .rlib file ${f}"
+			rm "${f}" || die
+		done
+	fi
+
+	eselect rust update
+
+	if has_version dev-debug/gdb || has_version llvm-core/lldb; then
+		elog "Rust installs helper scripts for calling GDB and LLDB,"
+		elog "for convenience they are installed under /usr/bin/rust-{gdb,lldb}-${PV}."
+	fi
+
+	if has_version app-editors/emacs; then
+		optfeature "emacs support for rust" app-emacs/rust-mode
+	fi
+
+	if has_version app-editors/gvim || has_version app-editors/vim; then
+		optfeature "vim support for rust" app-vim/rust-vim
+	fi
+}
+
+pkg_postrm() {
+	eselect rust cleanup
+}