Native Windows method without any 3^rd party tools:

winget install LLVM
# or
winget install --id=LLVM.LLVM -e

You can also install specific version if you don't want the latest one

winget install LLVM.LLVM --version 19.1.0

There are basically two ways to install LLVM on your Ubuntu 18.04 machine:

• Source
• Binary

Considering your question, it seems you would like to have a binary version of LLVM. Therefore you can install LLVM from your Ubuntu 18.04 terminal as following:

First of all, you should update packages as following:

• sudo apt-get update

However, for custom LLVM i.e. in your case LLVM 7:

• sudo apt-get install -y llvm-7
• sudo apt-get install -y llvm-7 llvm-7-dev llvm-7-tools clang-7

Do you want some LLVM-7 examples?

• sudo apt-get -y install llvm-7-examples

Do you want to remove LLVM-6?

• sudo apt-get purge llvm-6.0 clang-6.0
• sudo add-apt-repository --remove ppa:kxstudio-team/builds

For default LLVM installation you should run following (not for your case):

• sudo apt install llvm

• For detail packages please check LLVM Ubuntu nightly packages

However, currently the last version of LLVM is LLVM 13.0. 1. It is better to install the latest version.

check how to install LLVM here https://apt.llvm.org/ to retrieve the archive signature like this:

wget --no-check-certificate -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -

Add the PPAs where to install from:

add-apt-repository 'deb http://apt.llvm.org/bionic/   llvm-toolchain-bionic-10  main'

Update packages:

sudo apt update

Install default llvm & llvm-config:

sudo apt install llvm

Install custom version: llvm-10 & llvm-config-10:

sudo apt-get install llvm-10 lldb-10 llvm-10-dev libllvm10 llvm-10-runtime

Use "update-alternatives" to config alternatives like this for "llvm-config":

sudo update-alternatives --install /usr/bin/llvm-config llvm-config /usr/bin/llvm-config-6.0 6
sudo update-alternatives --install /usr/bin/llvm-config llvm-config /usr/bin/llvm-config-10 10
sudo update-alternatives --config llvm-config

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