Compiled on RPI3B with 5.10.77-piCore-v8
Can probably build this when compiling the main llvm package.

Compile Flags:
(passed in command)

Dependencies:
compiletc
llvm-dev
cmake
python3.8
ninja
clang

Commands:

cd /tmp

wget https://github.com/llvm/llvm-project/releases/download/llvmorg-13.0.1/lld-13.0.1.src.tar.xz
wget https://github.com/llvm/llvm-project/releases/download/llvmorg-13.0.1/libunwind-13.0.1.src.tar.xz

time tar -I pixz -xf lld-13.0.1.src.tar.xz
real    0m 0.52s
user    0m 0.29s
sys     0m 0.22s

time tar -I pixz -xf libunwind-13.0.1.src.tar.xz
real    0m 0.03s
user    0m 0.02s
sys     0m 0.01s

mv libunwind-13.0.1.src/include/mach-o/ lld-13.0.1.src/MachO/
cd lld-13.0.1.src/ && mkdir build && cd build
sudo busybox cp /tmp/tcloop/llvm-dev/usr/local/bin/llvm-config /usr/local/bin/llvm-config

time cmake -LAH -DCMAKE_C_FLAGS_RELEASE="-march=armv8-a+crc -mtune=cortex-a72 -Os -pipe" \
 -DCMAKE_CXX_FLAGS_RELEASE="-march=armv8-a+crc -mtune=cortex-a72 -Os -pipe" \
 -DCMAKE_BUILD_TYPE=Release -DLLVM_ENABLE_PROJECTS=lld -DCMAKE_INSTALL_PREFIX=/usr/local -G Ninja ..

sed -i 's:-O2 -g -DNDEBUG:-Os -DNDEBUG:g' CMakeCache.txt
sed -i 's:-Wl,-O3:-Wl,-Os:g' build.ninja

time ninja -j4
real    15m 13.57s
user    56m 40.35s
sys     2m 42.34s

DESTDIR=/tmp/packing-lld ninja install

llvm-strip --strip-unneeded /tmp/packing-lld/usr/local/bin/lld
llvm-strip --strip-debug /tmp/packing-lld/usr/local/lib/*.a