hgm wrote:As this problem now seems to be XBoard rather than timeseal, as was first thought, can you give me some pointers?
Not yet. What I will try to do later tomorrow after CCT is to run with debugging on and edit the thing to just include the game where the hang occurs. What we are seeing, however, is that a move is made on the server, and all the observers see it just fine, but xboard is never relaying it to the engine... But only on FICS as I have been using the latest xboard on ICC for a few months (since you added the smpCores and such) with zero problems. Got to be some sort of extra or missing characters that causes xboard to either not recognize the move, or something. I can not tell whether xboard updates but does not inform the engine, since it runs on my office box. I will have to wait until monday to do that, or else try to run some tests on my laptop.
Note that I hardly ever use XBoard myself, (only WinBoard), and that I do not have any 64-bit systems, so I certainly never tested 64-bit compiles of XBoard. WB and XB share the same back-end, though, and all ICS code is in the back-end. I have been using 4.4.x versions of WinBoard for years in on-line play, and I never where any problems (with 32-bit versions). Also other people never reported any problems until today. v4.4.x was around during the previous CCT already, and we never changed much in the 4.4.x branch, other than simple bug fixes. (All development was done in another branch.)
Note that Xaw3d is suspect: people report crashes when doing things that the X-server does (like enlarging the engine-output window). These problems go away when you compile with plain Xaw. This applies to the 32-bit version, however. Nevertheless, be sure to build with plain Xaw.
I'll try to help out by first capturing a failed game (debug) and then look at the fics-to-xboard communication at the point of failure. I still suspect some sort of data screw-up from FICS... since I have not seen this at all on ICC. And we were seeing several people have trouble, and it did not seem to be only 64 bit systems, but I am not certain about that...