``` Hi, On derivatives of FreeBSD that have net/pfvar.h, (GNU/kFreeBSD in my case, but there will be others), USE_TRANSPARENT gets defined but __FreeBSD__ is not. Therefore when running options/validate__transproxy in src/test/test_options.c: 1080 free_options_test_data(tdata); tdata remains a dangling pointer. It may be assigned a new value in one of the following ifdef blocks, which exist for linux, __FreeBSD__, DARWIN and __OpenBSD__. So in any other case when we reach: 1115 free_options_test_data(tdata); it would double-free the tdata from earlier. I've attached a simple patch to NULL that pointer the first time it is freed. I will follow up with another ticket to enable transproxy on GNU/kFreeBSD and enable this test to run on it. Thanks. Backtrace of the crash with -DNO_FORKING: #0 routerset_free (routerset=0x21) at src/or/routerset.c:411 cp_sl_idx = <optimized out> cp_sl_len = <optimized out> cp = <optimized out> #1 0x000000000061d4e0 in or_options_free (options=0xae1ad0) at src/or/config.c:800 No locals. #2 0x000000000051f3e5 in free_options_test_data (td=0xae2750) at src/test/test_options.c:391 No locals. #3 0x00000000005231f3 in test_options_validate__transproxy (ignored=<optimized out>) at src/test/test_options.c:1115 ret = <optimized out> tdata = 0xae2750 #4 0x00000000005ede8a in testcase_run_bare_ (testcase=0xaab430 <options_tests+400>) at src/ext/tinytest.c:106 env = 0x0 outcome = <optimized out> #5 testcase_run_one (group=0xaa61e0 <testgroups+512>, testcase=0xaab430 <options_tests+400>) at src/ext/tinytest.c:253 testcase = 0xaab430 <options_tests+400> group = 0xaa61e0 <testgroups+512> #6 0x00000000005ee51e in tinytest_main (c=c@entry=3, v=v@entry=0x7fffffffe5b8, groups=0xaa5fe0 <testgroups>) at src/ext/tinytest.c:435 i = 32 j = 10 n = <optimized out> #7 0x000000000040d04b in main (c=3, v=0x7fffffffe5b8) at src/test/testing_common.c:300 ``` **Trac**: **Username**: stevenc99