Source installation tries to install LLVM sources even if system LLVM used

[o01eg]

I'm trying to install rust with system LLVM and without src/llvm-project folder. It builds successfully but installation fails when trying to copy missing src/llvm-project/libunwind.

Copy "/tmp/portage/dev-lang/rust-9999/work/rust-git-src/library/alloc/benches/btree/map.rs" to "/tmp/portage/dev-lang/rust-9999/work/rust-git-src/build/tmp/tarball/rust-src/image/lib/rustlib/src/rust/library/alloc/benches/btree/map.rs"
Copy "/tmp/portage/dev-lang/rust-9999/work/rust-git-src/library/alloc/benches/binary_heap.rs" to "/tmp/portage/dev-lang/rust-9999/work/rust-git-src/build/tmp/tarball/rust-src/image/lib/rustlib/src/rust/library/alloc/benches/binary_heap.rs"
Copy "/tmp/portage/dev-lang/rust-9999/work/rust-git-src/library/alloc/Cargo.toml" to "/tmp/portage/dev-lang/rust-9999/work/rust-git-src/build/tmp/tarball/rust-src/image/lib/rustlib/src/rust/library/alloc/Cargo.toml"
thread 'main' panicked at 'could not read dir "/tmp/portage/dev-lang/rust-9999/work/rust-git-src/src/llvm-project/libunwind": Os { code: 2, kind: NotFound, message: "No such file or directory" }', lib.rs:1714:25
stack backtrace:
   0: rust_begin_unwind
             at /rustc/7ba605cd90d6467bda469d1cd2148ac32ea562bf/library/std/src/panicking.rs:593:5
   1: core::panicking::panic_fmt
             at /rustc/7ba605cd90d6467bda469d1cd2148ac32ea562bf/library/core/src/panicking.rs:67:14
   2: bootstrap::Build::read_dir
             at ./src/bootstrap/lib.rs:1714:25
   3: bootstrap::Build::recurse_
             at ./src/bootstrap/lib.rs:1650:18
   4: bootstrap::Build::cp_filtered
             at ./src/bootstrap/lib.rs:1645:9
   5: bootstrap::dist::copy_src_dirs
             at ./src/bootstrap/dist.rs:880:9
   6: <bootstrap::dist::Src as bootstrap::builder::Step>::run
             at ./src/bootstrap/dist.rs:921:9
   7: bootstrap::builder::Builder::ensure
             at ./src/bootstrap/builder.rs:2087:23
   8: <bootstrap::install::Src as bootstrap::builder::Step>::run
             at ./src/bootstrap/install.rs:278:23
   9: bootstrap::builder::Builder::ensure
             at ./src/bootstrap/builder.rs:2087:23
  10: <bootstrap::install::Src as bootstrap::builder::Step>::make_run
             at ./src/bootstrap/install.rs:274:9
  11: bootstrap::builder::StepDescription::maybe_run
             at ./src/bootstrap/builder.rs:315:13
  12: bootstrap::builder::StepDescription::run
             at ./src/bootstrap/builder.rs:354:21
  13: bootstrap::builder::Builder::run_step_descriptions
             at ./src/bootstrap/builder.rs:959:9
  14: bootstrap::builder::Builder::execute_cli
             at ./src/bootstrap/builder.rs:940:9
  15: bootstrap::Build::build
             at ./src/bootstrap/lib.rs:704:13
  16: bootstrap::main
             at ./src/bootstrap/bin/main.rs:74:5
  17: core::ops::function::FnOnce::call_once
             at /rustc/7ba605cd90d6467bda469d1cd2148ac32ea562bf/library/core/src/ops/function.rs:250:5
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
Traceback (most recent call last):
  File "/tmp/portage/dev-lang/rust-9999/work/rust-git-src/./x.py", line 50, in <module>
    bootstrap.main()
  File "/tmp/portage/dev-lang/rust-9999/work/rust-git-src/src/bootstrap/bootstrap.py", line 1111, in main
    bootstrap(args)
  File "/tmp/portage/dev-lang/rust-9999/work/rust-git-src/src/bootstrap/bootstrap.py", line 1086, in bootstrap
    run(args, env=env, verbose=build.verbose, is_bootstrap=True)
  File "/tmp/portage/dev-lang/rust-9999/work/rust-git-src/src/bootstrap/bootstrap.py", line 184, in run
    raise RuntimeError(err)
RuntimeError: failed to run: /tmp/portage/dev-lang/rust-9999/work/rust-git-src/build/bootstrap/debug/bootstrap install -vv --config=/tmp/portage/dev-lang/rust-9999/work/rust-git-src/config.toml -j6

config.toml:

changelog-seen = 2
[llvm]
download-ci-llvm = false
optimize = true
release-debuginfo = false
assertions = false
ninja = true
targets = "X86;Mips;NVPTX;RISCV;BPF;AArch64;WebAssembly"
experimental-targets = ""
link-shared = true


enable-warnings = false
[llvm.build-config]
CMAKE_VERBOSE_MAKEFILE = "ON"
CMAKE_C_FLAGS_RELEASE = "-O2 -march=native -pipe -fomit-frame-pointer"
CMAKE_CXX_FLAGS_RELEASE = "-O2 -march=native -pipe -fomit-frame-pointer"
CMAKE_EXE_LINKER_FLAGS_RELEASE = "-O1"
CMAKE_MODULE_LINKER_FLAGS_RELEASE = "-O1"
CMAKE_SHARED_LINKER_FLAGS_RELEASE = "-O1"
CMAKE_STATIC_LINKER_FLAGS_RELEASE = ""
[build]
build-stage = 2
test-stage = 2
doc-stage = 2
build = "x86_64-unknown-linux-gnu"
host = ["x86_64-unknown-linux-gnu"]
target = ["i686-unknown-linux-gnu","x86_64-unknown-linux-gnu","wasm32-unknown-unknown"]
docs = true
compiler-docs = true
submodules = false
python = "python3.11"
locked-deps = true
vendor = false
extended = true
tools = ["cargo","rustdoc","clippy","rustfmt","rust-analyzer","analysis","src"]
verbose = 2
sanitizers = false
profiler = false
cargo-native-static = false
[install]
prefix = "/usr/lib/rust/9999"
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 = false
debug-assertions = false
debug-assertions-std = false
debuginfo-level = 0
debuginfo-level-rustc = 0
debuginfo-level-std = 0
debuginfo-level-tools = 0
debuginfo-level-tests = 0
backtrace = true
incremental = false
default-linker = "x86_64-pc-linux-gnu-gcc"
parallel-compiler = false
description = "gentoo"
rpath = false
verbose-tests = true
optimize-tests = true
codegen-tests = true
dist-src = false
remap-debuginfo = true
lld = false
# 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 = false
backtrace-on-ice = true
jemalloc = false
lto = "fat"
[dist]
src-tarball = false
compression-formats = ["xz"]
compression-profile = "balanced"
[target.i686-unknown-linux-gnu]
ar = "x86_64-pc-linux-gnu-ar"
cc = "x86_64-pc-linux-gnu-gcc"
cxx = "x86_64-pc-linux-gnu-g++"
linker = "x86_64-pc-linux-gnu-gcc"
ranlib = "x86_64-pc-linux-gnu-ranlib"
llvm-libunwind = "no"
llvm-config = "/usr/lib/llvm/16/bin/llvm-config"
[target.x86_64-unknown-linux-gnu]
ar = "x86_64-pc-linux-gnu-ar"
cc = "x86_64-pc-linux-gnu-gcc"
cxx = "x86_64-pc-linux-gnu-g++"
linker = "x86_64-pc-linux-gnu-gcc"
ranlib = "x86_64-pc-linux-gnu-ranlib"
llvm-libunwind = "no"
llvm-config = "/usr/lib/llvm/16/bin/llvm-config"
[target.wasm32-unknown-unknown]
linker = "lld"
# wasm target does not have profiler_builtins https://bugs.gentoo.org/848483
profiler = false

OS: Gentoo Linux AMD64
Rustc version: 4a0402c

[LuuuXXX]

It seems that the src/llvm-project/libunwind directory is included by default when the installation of the source code is created.

rust/src/bootstrap/dist.rs

Lines 923 to 938 in 8771282

	copy_src_dirs(
	builder,
	&builder.src,
	&["library", "src/llvm-project/libunwind"],
	&[
	// not needed and contains symlinks which rustup currently
	// chokes on when unpacking.
	"library/backtrace/crates",
	// these are 30MB combined and aren't necessary for building
	// the standard library.
	"library/stdarch/Cargo.toml",
	"library/stdarch/crates/stdarch-verify",
	"library/stdarch/crates/intrinsic-test",
	],
	&dst_src,
	);

So, It is necessary to preserve that directory by updating the submodule.

[o01eg]

Should it be included even if not used by current rust installation?

[LuuuXXX]

The procedure for generating Src package requires src/llvm-project/libunwind, . You can simply remove src from tools in your config.toml to avoid outputting Src tar package.

rust/config.example.toml

Lines 302 to 319 in 8771282

	# Set of tools to be included in the installation.
	#
	# If `extended = false`, the only one of these built by default is rustdoc.
	#
	# If `extended = true`, they're all included, with the exception of
	# rust-demangler which additionally requires `profiler = true` to be set.
	#
	# If any enabled tool fails to build, the installation fails.
	#tools = [
	# "cargo",
	# "clippy",
	# "rustdoc",
	# "rustfmt",
	# "rust-analyzer",
	# "analysis",
	# "src",
	# "rust-demangler", # if profiler = true
	#]

[o01eg]

Isn't src tool required for rust-analyzer? I'd like to pass src/llvm-project/libunwind to copy_src_dirs depending on llvm-libunwind config.

[bjorn3]

In the past library/unwind/build.rs needed to build src/llvm-project/libunwind on some targets, so it had to be included in the standard library source tarball, but 4c9896f moved this building to rust's build system, so it should be fine to remove it from the standard library source tarball.