Build and install AFL++

Download the lastest devel version with:

$ git clone
$ cd AFLplusplus

AFL++ has many build options. The easiest is to build and install everything:

$ make distrib
$ sudo make install

Note that “make distrib” also builds llvm_mode, qemu_mode, unicorn_mode and more. If you just want plain afl then do “make all”, however compiling and using at least llvm_mode is highly recommended for much better results - hence in this case

$ make source-only

is what you should choose.

These build options exist:

  • all: just the main AFL++ binaries
  • binary-only: everything for binary-only fuzzing: qemu_mode, unicorn_mode, libdislocator, libtokencap, radamsa
  • source-only: everything for source code fuzzing: llvm_mode, libdislocator, libtokencap, radamsa
  • distrib: everything (for both binary-only and source code fuzzing)
  • install: installs everything you have compiled with the build options above
  • clean: cleans everything. for qemu_mode and unicorn_mode it means it deletes all downloads as well
  • code-format: format the code, do this before you commit and send a PR please!
  • tests: runs test cases to ensure that all features are still working as they should
  • help: shows these build options

Unless you are on Mac OS X you can also build statically linked versions of the AFL++ binaries by passing the STATIC=1 argument to make:

$ make all STATIC=1

Note that AFL++ is faster and better the newer the compilers used are. Hence gcc-9 and especially llvm-9 should be the compilers of choice. If your distribution does not have them, you can use the Dockerfile:

$ docker build -t aflplusplus