In article , Sascha Wilde writes: > I'm not intending to be a pita, but this is still an issue and I think > it should be further investigated and resolved. Thank you for keeping on attacking this problem. But... > If I can help, by sending debugger info or the like please tell me what > to do. as the reported phenomenon is so mysterious that I can't think of any good debugging strategy. :-( > On a second thought I think that my statement: > > So It seems the problem might really be a strange X11 bug, which is > > triggered by the new Emacs display code? > is somewhat to much of an excuse: The problem really only shows with > recent Emacs, not with any other application where I'm using exactly the > same fonts, nor with older (22) Emacsn. > More additional information, I don't know if its useful but it might > contain some hints for those who know the dirty details of Emacs > display... ;-) > I noticed the following phenomenon (which is really an extended version > of my observations from the last mail): > I have two systems, A and B, and two users foo and bar, they both have > access to the very same Emacs binary (over nfs) and they both can use > the same X display (via ssh -X). > My X-server runs an system A. > 1. I start Emacs with -Q as user bar on system B and do my C-h H test. > No problem when changing the default font to terminus. > After that I quit Emacs. > 2. I start Emacs as user foo on system A and do some work, until the > "vanished special chars" bug shows up. I keep that Emacs running and > ... > 3. ... start again Emacs -Q as bar on system B and do my C-h H test. > After changing the default font to terminus the umlauts are vanished > in this instance of Emacs, too! > Please note that the only thing the two Emacsn have in common is the > X Display, as they run on different hosts by different users. > 4. Now: when I quit both Emacsn and restart at 1. the bug is gone again! > So it affects all Emacsn on the same display once it appeared, but it > "heals" again when all affected Emacsn are closed... > Any ideas? Insights? Suggestions on how to proceed debugging this? As far as I can't reproduce the problem, I think there's no way other than you debug Emacs by gdb. As you wrote: ---------------------------------------------------------------------- C-u C-x = on the vanished `$(D)N(B' shows: [...] x:-xos4-terminus-medium-r-normal--16-160-72-72-c-80-iso10646-1 (#xDF) ---------------------------------------------------------------------- Please find a way to reproduce the problem with a buffer that contains only "$(D)N(B". Then, run Emacs under gdb as this: % cd .../src/emacs % gdb emacs (gdb) br xfont.c:833 (gdb) cond 3 len==1&& s->char2b.byte2==0xDF (gdb) run and repeat the above procedure. Emacs should stop at line 841. Then try this and see how screen changes: (gdb) ff (gdb) fin (gdb) ff See also emacs/etc/DEBUG. It has many hints for debugging Emacs with gdb. --- Kenichi Handa handa@ni.aist.go.jp