Installation

Mull ships as two kinds of packages:

• mull: mull-runner and mull-reporter, which work with any LLVM version
• mull-<N>: the compiler plugin and mull-instrument for LLVM <N>, which pull in mull

To install a precompiled package run one of the following commands.

The version number at the end must match the version of Clang/LLVM used.

# macOS
brew install mull-project/mull/mull@19

# Debian / Ubuntu
curl -1sLf 'https://dl.cloudsmith.io/public/mull-project/mull-stable/setup.deb.sh' | sudo -E bash
sudo apt-get install mull-19

# RedHat
curl -1sLf 'https://dl.cloudsmith.io/public/mull-project/mull-stable/setup.rpm.sh' | sudo -E bash
sudo yum install mull-19

If these fail with 402 Payment Required, see Cloudsmith bandwidth limit.

Check the installation:

mull-runner --version

The output should look similar:

mull-runner 0.36.0

Mull: Practical mutation testing and fault injection for C and C++
Home: https://mull-project.com
Plugins:
  /usr/lib/mull-ir-frontend-19 (mull 0.36.0, LLVM 19.1.7)

Note

Before 0.36.0 the tools had versioned names (mull-runner-19). They are still installed as symlinks to mull-runner and mull-reporter, but will be removed in a future release.

Cloudsmith bandwidth limit

Caution

The packages are hosted on Cloudsmith, which has a bandwidth limit. Once it’s reached, apt, yum and brew fail with 402 Payment Required.

In that case, download the packages from the latest GitHub release instead: mull and the plugin for your LLVM version, built for your OS. For example, for LLVM 19 on Ubuntu 24.04 (x86_64):

gh release download --repo mull-project/mull \
  --pattern 'Mull-[0-9].[0-9]*-ubuntu-amd64-24.04.deb' \
  --pattern 'Mull-19-*-ubuntu-amd64-24.04.deb'
sudo apt-get install ./Mull-*.deb

Without gh, download the same files from the release page.

Use sudo yum install ./Mull-*.rpm for the .rpm packages, and unpack the .zip packages on macOS. Packages installed this way don’t get updates.