Version ++4.20c (release)

! A new forkserver communication model is now introduced. afl-fuzz is
backward compatible to old compiled targets if they are not built
for CMPLOG/Redqueen, but new compiled targets will not work with
old afl-fuzz versions!
! Recompile all targets that are instrumented for CMPLOG/Redqueen!

• AFL++ now supports up to 4 billion coverage edges, up from 6 million.
• New compile option: make PERFORMANCE=1 - this will enable special
  CPU dependent optimizations that make everything more performant - but
  the binaries will likely won't work on different platforms. Also
  enables a faster hasher if the CPU requirements are met.
• The persistent record feature (see config.h) was expanded to also
  support replay, thanks to @quarta-qti !
• afl-fuzz:
  • the new deterministic fuzzing feature is now activated by default,
    deactivate with -z. Parameters -d and -D are ignored.
  • small improvements to CMPLOG/redqueen
  • workround for a bug with MOpt -L when used with -M - in the future
    we will either remove or rewrite MOpt.
  • fix for -t xxx+ feature
  • -e extension option now saves the queue items, crashes, etc. with the
    extension too
  • fixes for trimmming, correct -V time and reading stats on resume by eqv
    thanks a lot!
• afl-cc:
  • added collision free caller instrumentation to LTO mode. activate with
    AFL_LLVM_LTO_CALLER=1. You can set a max depth to go through single
    block functions with AFL_LLVM_LTO_CALLER_DEPTH (default 0)
  • fixes for COMPCOV/LAF and most other modules
  • fix for GCC_PLUGIN cmplog that broke on std::strings
• afl-whatsup:
  • now also displays current average speed
  • small bugfixes
• Fixes for aflpp custom mutator and standalone tool
• Minor edits to afl-persistent-config
• Prevent temporary files being left behind on aborted afl-whatsup
• More CPU benchmarks added to benchmark/