mono/Unity-build.md

Build Mono for Unity Uasges

Clone the repo

• Clone this repo into a directory that follows the structure required by our build scripts
• Create some root directory: mkdir my-mono
• Create the expected directory for the mono checkout : mkdir my-mono\mono
• If you have a github account: git clone git@github.com:Unity-Technologies/mono my-mono\mono
• Otherwise: git clone git://github.com/Unity-Technologies/mono my-mono/mono You won't be able to push back changes - if you need to do this, follow the instructions here: Unity on GitHub
• Pull the git submodules (this is required after cloning, and is often necessary when changing branches)
  • git submodule update --init --recursive
  • NOTE: If on windows, run in Git Bash to be able to enter a password

Build on Windows

Runtime

From the root of your cloned mono directory run:

• external\buildscripts\build_runtime_win.pl

or: Open msvc/mono.sln in Visual Studio and build the Runtime/libmono-dynamic project

• If you are on 2020.3 or older you can use VS 2015/VS 2019 as long as you don't upgrade the projects and have VS 2010 installed!

• Don't forget to select x64 platform if you intend to use the DLLs with the 64-bit Player/Editor!

• Artifacts will be in: \msvc\build\boehm\x64\bin\Debug

class libraries

• You can not build the class libraries on windows, so you will want to install WSL https://learn.microsoft.com/en-us/windows/wsl/install

• Our buildscript relies on an old Ubuntu version, chances are when you setup WSL you will have a more recent version. If you attempt to build you will get an error message that says "No usable version of libssl was found". To fix this issue, you want to install libssl 1.0 (you have a more recent version, and 1.0 is deprecated)

  Execute the following script in WSL to download libssl 1.0 and install it in /usr/local/ssl/ (credit to @danielo for the script )

wget https://www.openssl.org/source/openssl-1.0.2l.tar.gz tar -xzvf openssl-1.0.2l.tar.gz cd openssl-1.0.2l ./config -fPIC shared make # installs into /usr/local/ssl sudo make install sudo ldconfig /usr/local/ssl/lib ldconfig -p | grep libssl

You should see your libssl1.0 listed. If you do not, go to your /etc/ld.so.conf.d/ folder, pick one of the files here and add the path to /usr/local/ssl/lib in it, then run ldconfig. ldconfig -p | grep libssl should now list your lib.

From the root of your cloned mono directory run:

• perl external/buildscripts/build_classlibs_wsl.pl

Once you have built the class libraries successfully, a faster way of rebuilding is using the make file located in mcs/class and running:

• make PROFILE=unityjit HOST_PLATFORM=win32

Your artifacts will be in mcs/class/lib/unityjit-win32

Build on OSX

You need to install pkg-config. With Homebrew installed run:

• brew install pkg-config

Runtime

Optional - Enable debug build:

• Edit external/buildscripts/build_runtime_osx.pl and add '–debug=1' to the list of arguments passed to build.pl

• From the root of your cloned mono directory run:

  • perl external/buildscripts/build_runtime_osx.pl

Optional: If the build fails with the error "'mach_dep.lo' is not a valid libtool object" - disable parallel build by changing (external/buildscripts/build_runtime_osx.pl) my $jobs = 4 to my $jobs = 1 and try again.

After the building is completed you can verify that you have a good build universal dylib by running :

• file builds/embedruntimes/osx/libmonobdwgc-2.0.dylib

If you stumble upon the build script not being able to copy the main Mono .dylib symbols file (.dSYM) don't stress, the information is embedded.

class libraries

From the root of your cloned mono directory run:

• perl external/buildscripts/build_classlibs_osx.pl

Build on other platforms

• Run external/buildscripts/build_runtime_myplatform.pl (Runtime only) or
• Run ./autogen.sh followed by make. (All platforms (requires cygwin on windows))