Control: reassign -1 libpango-1.0-0 1.52.0+ds-1 Control: retitle -1 libpango-1.0-0: hangs in pango_fc_patterns_get_font_pattern (echo 'set terminal wxt; plot x' | gnuplot -persist) Control: forwarded -1 https://gitlab.gnome.org/GNOME/pango/-/issues/784 Control: affects -1 gnuplot-qt gnuplot-x11
On 2024-02-29 16:10:06 +0100, Vincent Lefevre wrote: > I've identified the "problematic" commit in Pango, and I would tend > to say that this is the reason: > > https://gitlab.gnome.org/GNOME/pango/-/commit/89442dae443eba2aa0f0a526b4d6d39c0c9b13c6 > > According to the commit message, a new thread was created "for every > single fontconfig call". Now "a single fontconfig thread per fontmap" > is used. So I suppose that this makes Pango faster, triggering the > race condition in gnuplot. (now a single thread using a queue instead of a thread per request) > I've updated the upstream gnuplot bug and opened a bug in Pango, > hoping confirmation: > > https://gitlab.gnome.org/GNOME/pango/-/issues/784 The backtrace I posted in the gnuplot and pango bugs shows that the hang occurs in pango_fc_patterns_get_font_pattern, i.e. in pango, in the source file changed by the above commit. So it is probably a bug in this new pango code, which is visible only under some conditions. -- Vincent Lefèvre <vinc...@vinc17.net> - Web: <https://www.vinc17.net/> 100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/> Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)
