C with Safety - Cyclone

Paul Smith writes: "New Scientist is carrying a story about a redesigned version of the programming language C called Cyclone from AT&T labs. "The Cyclone compiler identifies segments of code that could eventually cause such problems using a "type-checking engine". This does not just look for specific strings of code, but analyses the code's purpose and singles out conflicts known to be potentially dangerous.""

Comments

Re:Isn't that called "Java"?

[The_egghead]

There's a key difference here though. Java requires a run-time stack to do all of it's safety checking. This project aims to all of it's checking at compile time, so it's static, rather than dynamic. This is _VERY_ hard problem, and is where virtually all of the programming languages research is centered today. However, you're instinct that this is not a new concept is correct. Microsoft is actually doing very similar research in the form of a project called Vault.

Lclint

[Ed Avis]

A lot of the static checking made possible by Cyclone can be done for ordinary C with lclint, which lets you add annotations to C source code to express things like 'this pointer may not be null', 'this is the only pointer to the object' and so on. You write these assertions as special comments, for example /*@notnull@*/. These are checked by lclint but (of course) ignored by a C compiler so you compile as normal. (If you weaken the checking done, lclint can also act as a traditional 'lint' program.)

Also C++ provides a lot of the Cyclone features, not all of them, but it certainly has a stronger type system than C. I'd like to see something which combines all three: an lclint-type program that lets you annotate C++ code to provide the extra checks that Cyclone (and lclint) have over C++.