JDK-8370562 : Whitebox Fuzzer for C2
  • Type: Enhancement
  • Component: hotspot
  • Sub-Component: compiler
  • Affected Version: 26
  • Priority: P4
  • Status: Open
  • Resolution: Unresolved
  • Submitted: 2025-10-24
  • Updated: 2025-10-24
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Description
While there are existing fuzzers like javafuzzer that find bugs in C2, we find that the generated programs take quite a while to find and are overly contrived, whereas most C2 bugs (also those found by a fuzzer) have a rather small reproducer. Our hypothesis is that a fuzzer that instruments C2 for feedback (e.g. what optimizations took place) and takes existing test cases as seeds, could be guided to quicker and smaller finds. Further, such a fuzzer should also cover new java features currently not covered by other fuzzers we are employing.
Comments
Currently, Olivier Mattmann <olivier.mattmann@bluewin.ch>, a masters student from ETH Zürich, is working on such a fuzzer as his thesis project.
24-10-2025