Rustc-1.85.1

Installation of Rustc

To install into the /opt directory, remove any existing /opt/rustc symlink and create a new directory (i.e. with a different name if trying a modified build of the same version). As the root user:

mkdir -pv /opt/rustc-1.85.1 &&
ln -svfn rustc-1.85.1 /opt/rustc

Note

If multiple versions of Rustc are installed in /opt, changing to another version only requires changing the /opt/rustc symbolic link and then running ldconfig.

Create a suitable config.toml file which will configure the build.

cat > config.toml << "EOF" &&
# see config.toml.example for more possible options.
# Tell x.py the editors have reviewed the content of this file
# and updated it to follow the major changes of the building system,
# so x.py will not warn us to do such a review.
change-id = 134650

[llvm]
# When using system llvm prefer shared libraries
link-shared = true

# Do not download pre-built LLVM, instead either use the system
# LLVM or build LLVM from the shipped source.
download-ci-llvm = false

EOF
if [ ! -f /usr/lib32/libc.so.6 ]; then
cat >> config.toml << "EOF"
# If building the shipped LLVM source, only enable the x86 target
# instead of all the targets supported by LLVM.
targets = "X86"

EOF
fi
if [ -f /usr/lib32/libc.so.6 ]; then
cat >> config.toml << "EOF"
[build]
target = [
  "x86_64-unknown-linux-gnu",
  "i686-unknown-linux-gnu",
]

EOF
fi &&
cat >> config.toml << "EOF" &&
# omit docs to save time and space (default is to build them)
docs = false

# install extended tools: cargo, clippy, etc
extended = true

# Do not query new versions of dependencies online.
locked-deps = true

# Specify which extended tools (those from the default install).
tools = ["cargo", "clippy", "rustdoc", "rustfmt"]

[install]
prefix = "/opt/rustc-1.85.1"
docdir = "share/doc/rustc-1.85.1"

[rust]
channel = "stable"
description = "for GLFS #f2b2"

# Uncomment if FileCheck has been installed.
#codegen-tests = false

# Enable the same optimizations as the official upstream build.
lto = "thin"
codegen-units = 1

EOF
if [ -f /usr/lib32/libc.so.6 ]; then
cat >> config.toml << "EOF"
[target.x86_64-unknown-linux-gnu]
cc = "/usr/bin/gcc"
cxx = "/usr/bin/g++"
ar = "/usr/bin/gcc-ar"
ranlib = "/usr/bin/gcc-ranlib"
llvm-config = "/usr/bin/llvm-config"

[target.i686-unknown-linux-gnu]
cc = "/usr/bin/gcc"
cxx = "/usr/bin/g++"
ar = "/usr/bin/gcc-ar"
ranlib = "/usr/bin/gcc-ranlib"
EOF
else
cat >> config.toml << "EOF"
[target.x86_64-unknown-linux-gnu]
llvm-config = "/usr/bin/llvm-config"

[target.i686-unknown-linux-gnu]
llvm-config = "/usr/bin/llvm-config"
EOF
fi

Note

The above commands will create config.toml differently depending on if a few checks pass/fail. This was done to avoid confusion.

Now apply a patch to fix building with LLVM-20.1.1:

patch -Np1 -i ../rustc-1.85.1-upstream_fixes_llvm-1.patch

Compile Rust by running the following commands:

./x.py build

Now, as the root user, install the package:

./x.py install rustc std &&
./x.py install --stage=1 cargo clippy rustfmt

Still as the root user, fix the installation of the documentation and symlink a Zsh completion file into the correct location and move a Bash completion file into the location recommended by the Bash completion maintainers:

rm -fv /opt/rustc-1.85.1/share/doc/rustc-1.85.1/*.old   &&
install -vm644 README.md                                \
               /opt/rustc-1.85.1/share/doc/rustc-1.85.1 &&

install -vdm755 /usr/share/zsh/site-functions      &&
ln -sfv /opt/rustc/share/zsh/site-functions/_cargo \
        /usr/share/zsh/site-functions              &&

mv -v /etc/bash_completion.d/cargo \
      /usr/share/bash-completion/completions