Server segfault

Submitted by computerguy505 on Sun, 2013-04-07 01:49

Forums:

When I run MOC (svn version), it appears to go fine until it suddenly stops and says

FATAL_ERROR: Server exited!

After messing around with gdb and getting it to follow the child fork (the server), I was able to track it down to a segfault on line 1144 of tags_cache.c, c->db_env->set_msgcall (c->db_env, db_msg_cb);.

I have no clue about anything with BerkeleyDB, so I don't really know what this line does or why it might be causing problems. I didn't file this under bug reports because I think it may be a problem with my db installation. This is on a newly installed arch install that may have some screwiness that I am unaware of.

Any help would be appreciated.

computerguy505

Sun, 2013-04-07 02:00

I didn't really specify this well, but the error comes up after the driver is detected (alsa in my case) but before the gui is initialized.

jcf

Sun, 2013-04-07 03:10

... especially as the near-identical line above executed without problems. We pounded this area of code recently in testing the solution to another problem and I have had no reports of this problem from other users (but someone always has to report it first).

  • Which SVN revision of MOC are you using?
  • Did you rebuild MOC on the newly installed system?
  • Which version of BDB are you linking against?

computerguy505

Sun, 2013-04-07 15:04

Yes, the above line runs fine.

The latest commit according to svn log is

<br /> r2526 | jcf | 2013-02-18 22:09:44 -0500 (Mon, 18 Feb 2013) | 1 line</p> <p>Provide locking support for FFmpeg's non-thread-safe functions.<br />

sudo pacman -S db gives me

<br /> warning: db-5.3.21-1 is up to date -- reinstalling<br /> resolving dependencies...<br /> looking for inter-conflicts...</p> <p>Packages (1): db-5.3.21-1</p> <p>Total Installed Size: 15.30 MiB<br /> Net Upgrade Size: 0.00 MiB</p> <p>:: Proceed with installation? [Y/n] n<br />

Just yesterday I cloned it and immediately ran ./configure. After that I modified the hard-coded strings in the screen_set_title function in interface_elements.c to be shorter. I then ran make. That didn't work. With mocp -D I got

<br /> Loading plugins from /usr/local/lib/moc/decoder_plugins...<br /> Loading plugin libaac_decoder...<br /> OK<br /> Loading plugin libffmpeg_decoder...<br /> OK<br /> Loading plugin libflac_decoder...<br /> OK<br /> Loading plugin libmodplug_decoder...<br /> OK<br /> Loading plugin libmp3_decoder...<br /> OK<br /> Loading plugin libsndfile_decoder...<br /> OK<br /> Loading plugin libspeex_decoder...<br /> OK<br /> Loading plugin libvorbis_decoder...<br /> OK<br /> Loading plugin libwavpack_decoder...<br /> OK<br /> Running the server...<br /> Trying JACK...<br /> Trying ALSA...</p> <p>FATAL_ERROR: Server exited!<br />

computerguy505

Sun, 2013-04-07 15:14

I have no clue why, but it has magically started working now. Maybe it's because I reinstalled db (like about but answering y). Probably something just went wrong when I installed db the first time.

Thanks, though!

jcf

Sun, 2013-04-07 19:38

I reproduced what you did as closely as possible but had no problem. Some glitch in the BDB install would explain it.