Sorry about the HTML.
I removed the string "-O2" from the /auth Makefile and, for good measure, did make clean, make and make install for all of Dovecot.
Still, it crashed when trying to log in via IMAP (webmail). Core dumped, here's the backtrace.
[snip] Core was generated by `dovecot/auth -w'. Program terminated with signal 11, Segmentation fault. #0 0x00000000 in ?? () (gdb) bt full #0 0x00000000 in ?? () No symbol table info available. #1 0x0805b0c7 in auth_worker_handle_user (client=0x82754d0, id=2, args=0x82601c8) at auth-worker-client.c:405 auth_request = 0x82776e8 userdb_id = 1 #2 0x0805b630 in auth_worker_handle_line (client=0x82754d0, line=0x82757da "2\tUSER\t1\tuser=mgoldXX@goldey.net\tservice=imap\toriginal_username=mgoldXX@goldey.net\trequested_login_user\tlip=127.0.0.1\trip=127.0.0.1\tlport=143\trport=47574\tsecured=1\tsuccessful=1\tmech=PLAIN") at auth-worker-client.c:534 args = 0x82601c0 id = 2 ret = false #3 0x0805b890 in auth_worker_input (client=0x82754d0) at auth-worker-client.c:614 _data_stack_cur_id = 3 line = 0x82757da "2\tUSER\t1\tuser=mgoldXX@goldey.net\tservice=imap\toriginal_username=mgoldXX@goldey.net\trequested_login_user\tlip=127.0.0.1\trip=127.0.0.1\tlport=143\trport=47574\tsecured=1\tsuccessful=1\tmech=PLAIN" ret = 183 #4 0xb7726021 in io_loop_call_io (io=0x8275688) at ioloop.c:384 ioloop = 0x8268398 t_id = 2 #5 0xb77270d3 in io_loop_handler_run (ioloop=0x8268398) at ioloop-epoll.c:213 ctx = 0x8273f38 event = 0x8273f78 list = 0x82756b0 io = 0xbf80049f tv = {tv_sec = 2147483, tv_usec = 0} msecs = 1 ret = 1 i = 0 j = 0 call = 192 #6 0xb7725fa0 in io_loop_run (ioloop=0x8268398) at ioloop.c:405 No locals. #7 0xb7711baa in master_service_run (service=0x82682e8, callback=0x805e466 <worker_connected>) at master-service.c:481 No locals. #8 0x0805e7aa in main (argc=2, argv=0x82681c0) at main.c:298 c = -1
And, for good measure:
(gdb) fr 1 #1 0x0805b0c7 in auth_worker_handle_user (client=0x82754d0, id=2, args=0x82601c8) at auth-worker-client.c:405 405 auth_request->userdb->userdb->iface->
(gdb) p *auth_request->userdb->userdb $1 = {args = 0x8268d10 "", cache_key = 0x0, blocking = true, id = 1, init_refcount = 1, iface = 0x807b320}
(gdb) p *auth_request->userdb->userdb->iface $2 = {name = 0x8074f3d "vpopmail", preinit = 0x8069a27 <vpopmail_preinit>, init = 0, deinit = 0, lookup = 0x806975f <vpopmail_lookup>, iterate_init = 0, iterate_next = 0, iterate_deinit = 0}
This is all Greek to me, but I'm happy to do more troubleshooting.
--mhg