InvisiCaps: The Fil-C Capability Model
Summary
The article introduces Fil-C's InvisiCaps, a pointer-capability model designed to enforce memory safety in C/C++. It explains the two-part pointer structure (lower bound and intval), the concept of flight pointers and pointers at rest, and how an auxiliary allocation enables safe pointer metadata handling, including support for atomic pointers and garbage collection friendliness. It also positions InvisiCaps against SoftBound and CHERI and covers practical implementation details and considerations.