Writing Your Own Toy Compiler Using Flex, Bison and LLVM Update (March 19 2010): this article was updated for LLVM 2.6 thanks to a great patch by John Harrison. He rocks! I’ve always been interested in compilers and languages, but interest only gets you so far. A lot of the concepts of compiler design can easily go way over most programmers’ heads, even the intelligent ones. Needless to say, I’ve