How do I compile the code under Mono?

Getting Mono

Previously, you had to build Mono from SVN. Instruction is still provided below in case it is needed again. But you can use Mono 1.9 release just fine.

Reference: http://www.mono-project.com/AnonSVN

svn co svn://anonsvn.mono-project.com/source/trunk/mono 
svn co svn://anonsvn.mono-project.com/source/trunk/mcs 
cd mono
./configure
make
make install

If you built Mono from source, make sure pkg-config can find the built Mono. For example: export PKG_CONFIG_PATH="/opt/mono/lib/pkgconfig"

Build IronRuby from SVN

Tested version r112. You can use SVN's -r option to checkout or to update to the specified revision.

svn co -r 112 http://ironruby.rubyforge.org/svn/trunk ironruby 
cd ironruby 
patch -p0 < patch-mono-r112 
rake compile mono=1 
mono build/mono_debug/ir.cmd