Latest HG reproducibly crashes when accessing a virtual namespace:

Apr 22 14:49:38 spectre dovecot: master: Dovecot v2.2.12 (09c114091c88) starting up for imap, lmtp […] Apr 22 14:50:05 spectre dovecot: imap(tlx@leuxner.net): Panic: file mail-storage.c: line 1735 (mailbox_notify_changes): assertion failed: (box->opened) Apr 22 14:50:05 spectre dovecot: imap(tlx@leuxner.net): Error: Raw backtrace: /usr/lib/dovecot/libdovecot.so.0(+0x6bbaf) [0x7f7dad859baf] -> /usr/lib/dovecot/libdovecot.so.0(+0x6bc0e) [0x7f7dad859c0e] -> /usr/lib/dovecot/libdovecot.so.0(i_fatal+0) [0x7f7dad81328e] -> /usr/lib/dovecot/libdovecot-storage.so.0(+0x81fda) [0x7f7dadb45fda] -> /usr/lib/dovecot/modules/lib20_virtual_plugin.so(+0x8ca3) [0x7f7dabffbca3] -> dovecot/imap tlx@leuxner.net 95.223.79.50 IDLE [0x410495] -> dovecot/imap tlx@leuxner.net 95.223.79.50 IDLE [0x41839c] -> dovecot/imap tlx@leuxner.net 95.223.79.50 IDLE [0x417400] -> dovecot/imap tlx@leuxner.net 95.223.79.50 IDLE [0x4174ba] -> dovecot/imap tlx@leuxner.net 95.223.79.50 IDLE [0x417775] -> dovecot/imap tlx@leuxner.net 95.223.79.50 IDLE [0x417b22] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_call_io+0x4e) [0x7f7dad86a91e] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_handler_run_internal+0xd7) [0x7f7dad86b917] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_handler_run+0x9) [0x7f7dad86a9a9] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_run+0x38) [0x7f7dad86aa28] -> /usr/lib/dovecot/libdovecot.so.0(master_service_run+0x13) [0x7f7dad818633] -> dovecot/imap tlx@leuxner.net 95.223.79.50 IDLE [0x40c128] -> /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xfd) [0x7f7dad481ead] -> dovecot/imap tlx@leuxner.net 95.223.79.50 IDLE [0x40c28d] Apr 22 14:50:05 spectre dovecot: imap(tlx@leuxner.net): Fatal: master: service(imap): child 25774 killed with signal 6 (core not dumped)

I'm not sure how to generate a core in this scenario, but commenting out the namespace configuration seems to prevent crashes for now. This appears to have been introduced in the last 5 days mercurial updates according to logs.

Previously working namespace:

namespace { prefix = Virtual/ separator = / location = virtual:~/mdbox/virtual }

Regards Thomas