What is "treelang"

Treelang is a "toy" programming language distributed with the GNU Compiler Collection (GCC) to demonstrate the features of its code-generation backend. It was developed by Tim Josling, based on a language called Toy created by Richard Kenner. During the GCC 4.3 release cycle, a patch was committed to remove the language, because of high maintenance costs outweighing its benefits and also because it was no longer considered a good front-end example by GCC developers.