Safe Systems Programming Languages

The C programming language provides explicit memory management, precise control over low-level data representations and high code efficiency. These features are indispensable for systems programming. However, C achieved these goals at the cost of sacrificing type safety. Safety violations like array out-of-bound accesses and dangling pointer accesses lead to a huge amount of well-known software bugs and malicious attacks. This paper surveys languages and tools for type-safe systems programming, including SafeC, CCured, Vault and Cyclone. Techniques such as code transformation, dynamic safety checking, static analysis, regionbased memory management and linear type systems are used to provide type safety for C-like languages. We motivate the use of such languages and tools, present their approaches with examples and explanations, compare them in various aspects and discuss their trade-offs. We present some similarities and dualities among these langauges and provide thoughts about future research directions.