Compiled on RPI3B with 5.10.77-piCore-v8

Reference:
https://www.linuxfromscratch.org/blfs/view/svn/general/rust.html
Requires a few gigs of swap space

Compile Flags:
None --> assigning flags actually increase the overall size 313.3M --> 356.8M

Dependencies:
python3.8
compiletc
cmake
curl-dev
libssh2-dev
clang
llvm-dev
ninja
pigz # not required, just to speed up the extraction time
tar  # not required, just to speed up the extraction time

Commands:

/usr/local/bin/tar -I pigz -xf rustc-1.59.0-src.tar.gz

cd rustc-1.59.0-src

cp ../config.toml .

sudo busybox cp -f /tmp/tcloop/llvm-dev/usr/local/bin/llvm-config /usr/local/bin

PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
export PATH

RUSTFLAGS='-C link-args=-lffi'
SSL_CERT_FILE=/usr/local/etc/ssl/certs/ca-certificates.crt
LIBSSH2_SYS_USE_PKG_CONFIG=1
export RUSTFLAGS SSL_CERT_FILE LIBSSH2_SYS_USE_PKG_CONFIG

time python3 ./x.py build --exclude src/tools/miri &> /tmp/rust-build.log && \
DESTDIR=/tmp/packing-rust time python3 ./x.py install &> /tmp/rust-install.log
# takes around 26~27 hours on pi3 / 5~6 hours on pi4

cd /tmp/packing-rust

# remove doc man
rm -fr ./usr/local/share/[dm][oa][cn]

find -type f -exec file {} ';' > /tmp/file.info

grep 'current ar archive' /tmp/file.info | cut -d : -f 1 | xargs llvm-strip --strip-debug

grep ELF /tmp/file.info | cut -d : -f 1 | xargs llvm-strip --strip-unneeded