A Compiler with a Good Clang

You probably already know, Apple has open-sourced its new front-end for C-like languages, that has been in development internally for months. Its name is "clang" which is probably a contraction of C LANGuage. This name might be related to the email handle of one of its creators Chris Lattner, who is clattner at apple. Its other father is Steve Naroff, who introduced it at the LLVM-developers' meeting back in May.

Of course, nobody writes a C compiler in six months, so this product is not mature yet, its main omission being structure handling, and there are many loose ends to wrap up. Being open source now, with a developer-friendly BSD license, I offered to fill in a bit-sized hole in the implementation, and chose _Complex multiplication and comparison operators. The parsing part was already done, AST handling too, only code generation to LLVM IR remaining to be done. I used the analogy principle (addition was already there) and came up with a patch in 30 minutes. After some IRC conversation with Chris and another round of tweaks, I got green light and checked in my changes accompanied with a test. That's it. This is open source at work. Trust, ease of implementation (I barely wrote 30 lines, because of the support for assembling fragments of LLVM is pretty good) plus rigorous code review and finally testcases. There is not much room for bugs and malicious code to hide out.

It has been a pleasurable experience. I know C++ code that is a nightmare in comparison. If the fathers of clang continue as they started and let the many external contributors fill in the missing pieces, this compiler will definitely be one with a good "Klang" (sound, in German).