tor_fragile_assert hit in connection_ap_handshake_rewrite_and_attach
Nov 10 16:45:46.971 [warn] tor_bug_occurred_(): Bug: src/or/connection_edge.c:1775: connection_ap_handshake_rewrite_and_attach: This line should not have been reached. (Future instances of this warning will be silenced.) (on Tor 0.3.0.0-alpha-dev 0980787f91cfc420)
Nov 10 16:45:46.972 [warn] Bug: Line unexpectedly reached at connection_ap_handshake_rewrite_and_attach at src/or/connection_edge.c:1775. Stack trace: (on Tor 0.3.0.0-alpha-dev 0980787f91cfc420)
Nov 10 16:45:46.972 [warn] Bug: src/or/tor(log_backtrace+0x42) [0x7fbee4aed262] (on Tor 0.3.0.0-alpha-dev 0980787f91cfc420)
Nov 10 16:45:46.972 [warn] Bug: src/or/tor(tor_bug_occurred_+0xb7) [0x7fbee4b05e67] (on Tor 0.3.0.0-alpha-dev 0980787f91cfc420)
Nov 10 16:45:46.972 [warn] Bug: src/or/tor(connection_ap_handshake_rewrite_and_attach+0xe3a) [0x7fbee4a9cf8a] (on Tor 0.3.0.0-alpha-dev 0980787f91cfc420)
Nov 10 16:45:46.972 [warn] Bug: src/or/tor(connection_edge_process_inbuf+0x1d0) [0x7fbee4a9d9c0] (on Tor 0.3.0.0-alpha-dev 0980787f91cfc420)
Nov 10 16:45:46.972 [warn] Bug: src/or/tor(+0xfbbb8) [0x7fbee4a95bb8] (on Tor 0.3.0.0-alpha-dev 0980787f91cfc420)
Nov 10 16:45:46.972 [warn] Bug: src/or/tor(+0x457b1) [0x7fbee49df7b1] (on Tor 0.3.0.0-alpha-dev 0980787f91cfc420)
Nov 10 16:45:46.972 [warn] Bug: /usr/lib/x86_64-linux-gnu/libevent-2.0.so.5(event_base_loop+0x7fc) [0x7fbee40233dc] (on Tor 0.3.0.0-alpha-dev 0980787f91cfc420)
Nov 10 16:45:46.972 [warn] Bug: src/or/tor(do_main_loop+0x234) [0x7fbee49e0834] (on Tor 0.3.0.0-alpha-dev 0980787f91cfc420)
Nov 10 16:45:46.972 [warn] Bug: src/or/tor(tor_main+0x1c25) [0x7fbee49e3f85] (on Tor 0.3.0.0-alpha-dev 0980787f91cfc420)
Nov 10 16:45:46.972 [warn] Bug: src/or/tor(main+0x19) [0x7fbee49dc119] (on Tor 0.3.0.0-alpha-dev 0980787f91cfc420)
Nov 10 16:45:46.972 [warn] Bug: /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5) [0x7fbee2ff4b45] (on Tor 0.3.0.0-alpha-dev 0980787f91cfc420)
Nov 10 16:45:46.972 [warn] Bug: src/or/tor(+0x42169) [0x7fbee49dc169] (on Tor 0.3.0.0-alpha-dev 0980787f91cfc420)
See #20494 (moved) for something related but apparently not the same.
Repeatably triggerable by "torify wget seul.org".