CC=afl-clang-fast CXX=afl-clang-fast++ AFL_USE_ASAN=1 ./configure --disable-ipv6

Passes fine.

AFL_USE_ASAN=1 make

Ends with the following:

Parser/pgen ./Grammar/Grammar Include/graminit.h Python/graminit.c

=================================================================
==29392==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 12416 byte(s) in 8 object(s) allocated from:
    #0 0x4a1f2e in realloc (/root/cpython/Parser/pgen+0x4a1f2e)
    #1 0x4cfcca in PyMem_RawRealloc /root/cpython/Objects/obmalloc.c:414:12

Indirect leak of 2080 byte(s) in 3 object(s) allocated from:
    #0 0x4a1f2e in realloc (/root/cpython/Parser/pgen+0x4a1f2e)
    #1 0x4cfcca in PyMem_RawRealloc /root/cpython/Objects/obmalloc.c:414:12

Indirect leak of 898 byte(s) in 86 object(s) allocated from:
    #0 0x4a1c3b in __interceptor_malloc (/root/cpython/Parser/pgen+0x4a1c3b)
    #1 0x7fbd7abe3989 in __strdup /build/glibc-uPj9cH/glibc-2.19/string/strdup.c:42

Indirect leak of 520 byte(s) in 1 object(s) allocated from:
    #0 0x4a1c3b in __interceptor_malloc (/root/cpython/Parser/pgen+0x4a1c3b)
    #1 0x4d3fa0 in PyMem_RawMalloc /root/cpython/Objects/obmalloc.c:396:12
    #2 0x4d3fa0 in _PyObject_Alloc /root/cpython/Objects/obmalloc.c:1467

Indirect leak of 178 byte(s) in 33 object(s) allocated from:
    #0 0x4a1c3b in __interceptor_malloc (/root/cpython/Parser/pgen+0x4a1c3b)
    #1 0x4c6756 in translabel /root/cpython/Parser/grammar.c:197:28
    #2 0x4c6756 in _Py_translatelabels /root/cpython/Parser/grammar.c:141

SUMMARY: AddressSanitizer: 16092 byte(s) leaked in 131 allocation(s).
Makefile:804: recipe for target 'Include/graminit.h' failed
make: *** [Include/graminit.h] Error 23