How to build EDK2 with GCC 12

EDK2 (tianocore) is a UEFI reference implementation that is almost entirely FOSS. Sadly, the documentation is lacking, and building it on modern systems takes a lot of trial and error. The easiest method was to use a Ubuntu 16.06 container, but a new build system was fully adopted a few months ago. This made it much easier to build, although the docs are still wrong in a few places. After looking at the new CI code, I managed to get a working build on a fresh Fedora 37 install.

Setting Up the Build Environment

There are two main ways to get the required dependencies, you can either use a pre-built Fedora or Ubuntu container from tianocore, or you can install the dependencies manually. Installing the dependencies manually gives you more freedom, but the container is easier to use and is supported by tianocore.

Using the official container

Tianocore provides a container with the required dependencies already installed. Run the container with podman:
```
podman run -it --name edk2-build -v ~/:/root/ ghcr.io/tianocore/containers/fedora-37-build:latest
```

Using a normal Fedora system

Install dependencies with DNF:

dnf install acpica-tools dotnet-runtime-6.0 curl gcc-c++ gcc lcov libX11-devel libXext-devel libuuid-devel make nuget nasm python3 python3-distutils-extra python3-pip python3-setuptools nodejs npm

If you are cross-compiling, run:

dnf install gcc-aarch64-linux-gnu gcc-arm-linux-gnu gcc-riscv64-linux-gnu
export GCC5_AARCH64_PREFIX="/usr/bin/aarch64-linux-gnu-"
export GCC5_ARM_PREFIX="/usr/bin/arm-linux-gnu-"
export GCC5_RISCV64_PREFIX="/usr/bin/riscv64-linux-gnu-"

Setting up EDK2

Clone the repo:

git clone https://github.com/tianocore/edk2 && cd edk2
git submodule update --init --recursive

Build the base tools:
```
make -C BaseTools
```

Create and enter a venv:

python3 -m venv .venv
source .venv/bin/activate

Install dependencies for the build system:

pip install -r pip-requirements.txt --upgrade

Install extra dependencies:
```
npm install -g cspell markdownlint-cli
```

Building EDK2

Set information about the build:

ARCH=X64 # CPU Architecture
PLATFORM=/path/to/Platform.py
PACKAGE=NameOfPackage # Name of package
TYPE=RELEASE # `RELEASE` or `DEBUG`
ARGS="BLD_*_EXAMPLE_OPTION=1" # Use`BLD_*_` instead of `-D`

Install compile-time dependencies, then start the build:

stuart_update -c $PLATFORM
stuart_setup-c $PLATFORM
stuart_build -c $PLATFORM -p $PACKAGE -a $ARCH TARGET=$TYPE TOOL_CHAIN_TAG=GCC5 $ARGS

The results of the build can be found in ./Build

Example config for building OVMF

This will build OVMF for x86_64 with secure boot and TPM support enabled.