<scp>ClosureX:</scp> Compiler Support for Correct Persistent Fuzzing

Fuzzing is a widely adopted and pragmatic methodology for bug hunting as a means of software hardening. Research reveals that increasing fuzzing throughput directly increases bug discovery rate. The highest performance fuzzing strategy is persistent fuzzing, which reuses a single process for all test cases by looping back to the start upon completion, instead of exiting. This eliminates all process creation, initialization, and tear-down costs---which are on-par with execution cost. Unfortunately, persistent fuzzing leads to semantically inconsistent program states because process state changes from one test case remain for subsequent test cases. This semantic inconsistency results in missed crashes, false crashes, and overall incorrectness that undermines fuzzer effectiveness.