wxt thread-wait problem

[Allin Cottrell]

I'm running current CVS gnuplot on Arch linux, linked with wxgtk2
3.0.3, and I'm seeing the program aborting on exit. Not on every
invocation -- this mostly happens when I run a script which generates
several plots, via separate calls to gnuplot, using the wxt terminal
with the -persist command-line flag.

If instead I run the gnuplot 5.0.6 that's supplied with Arch (linked
with the same wxWidgets library), the problem does not occur.

Here's an example of what I'm seeing on stderr using the CVS code;

The program 'gnuplot' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadMatch (invalid parameter attributes)'.
(Details: serial 519 error_code 8 request_code 130 minor_code 3)
(Note to programmers: normally, X errors are reported
asynchronously;
that is, you will receive the error a while after causing it.
To debug your program, run it with the --sync command line
option to change this behavior. You can then get a meaningful
backtrace from your debugger if you break on the gdk_x_error()
function.)
Gnuplot exiting abnormally. Trying to execute exit handlers anyway.
./src/unix/threadpsx.cpp(1480): assert "This() != this" failed in
Wait(): a thread can't wait for itself [in thread 7f83ce033700]

Call stack:
[00] wxOnAssert(char const*, int, char const*, char const*, wchar_t
const*)
[01] wxThread::Wait(wxThreadWait)
[02] wxt_atexit()
/home/cottrell/cfiles/gp-cvs/linux/src/../../gnuplot5/src/wxterminal/wxt_gui.cpp:4093
[03] gp_exit_cleanup
/home/cottrell/cfiles/gp-cvs/linux/src/../../gnuplot5/src/stdfn.c:451
[04] 0x7f83da650298
[05] 0x7f83da6502ea
[06] 0x7f83dc5c5874
[07] _XError
[08] 0x7f83ded94617
[09] 0x7f83ded946d5
[10] _XReply
[11] XTranslateCoordinates
[12] 0x7f83dc5cca38
[13] gdk_window_get_origin
[14] wxWindow::DoClientToScreen(int*, int*) const
[15] 0x7f83de25fd06
[16] 0x7f83de262e10
[17] 0x7f83dc9487ac
[18] g_closure_invoke
[19] 0x7f83dd4ba4ee
[20] g_signal_emit_valist