>>> Alternatively, instead of running emacs under gdb, you could just run emacs as you normally do and then attach gdb when emacs freezes. >>("gdb -p ") At that point, a backtrace of all threads would be useful. >> It happened again. Attached to PID as shown above. (gdb) list gave same result as above. >> (gdb) bt >> #0 0x00000000773bafb1 in ntdll!DbgBreakPoint () from >> /cygdrive/c/Windows/SYSTEM32/ntdll.dll >> #1 0x0000000077462e08 in ntdll!DbgUiRemoteBreakin () from >> /cygdrive/c/Windows/SYSTEM32/ntdll.dll >> #2 0x00000000772659cd in KERNEL32!BaseThreadInitThunk () from >> /cygdrive/c/Windows/system32/kernel32.dll >> #3 0x000000007739a561 in ntdll!RtlUserThreadStart () from >> /cygdrive/c/Windows/SYSTEM32/ntdll.dll >> #4 0x0000000000000000 in ?? () >> Backtrace stopped: previous frame inner to this frame (corrupt stack?) >> >> Does this tell me the problem is not Cygwin? Perhaps BLODA or bad hardware, maybe bad mouse? > >Not yet. When you attach gdb to a process, it creates a new thread to be used by gdb. What you're seeing above is the backtrace in that thread. >You need to switch to the main thread before you can get a useful backtrace: > >(gdb) thread 1 >(gdb) bt >Ken Here it is: (gdb) bt #0 0x00000001004e4e57 in readable_events (flags=1) at /usr/src/debug/emacs-26.1-1/src/keyboard.c:3338 #1 0x00000001004e5a85 in get_input_pending (flags=flags@entry=1) at /usr/src/debug/emacs-26.1-1/src/keyboard.c:6824 #2 0x00000001004e5b3d in swallow_events (do_display=do_display@entry=false) at /usr/src/debug/emacs-26.1-1/src/keyboard.c:4264 #3 0x0000000100592e0e in wait_reading_process_output (time_limit=, nsecs=, read_kbd=read_kbd@entry=0, do_display=do_display@entry=false, wait_for_cell=4305482867, wait_proc=wait_proc@entry=0x0, just_wait_proc=just_wait_proc@entry=0) at /usr/src/debug/emacs-26.1-1/src/process.c:5547 #4 0x00000001004c5d19 in x_get_foreign_selection (selection_symbol=, target_type=9360, time_stamp=0, frame=25790477765) at /usr/src/debug/emacs-26.1-1/src/xselect.c:1201 #5 0x0000000100551ab0 in Ffuncall (nargs=, args=args@entry=0xffffaef8) at /usr/src/debug/emacs-26.1-1/src/eval.c:2769 #6 0x0000000100588100 in exec_byte_code (bytestr=, vector=4294947221, maxdepth=, args_template=args_template@entry=4106, nargs=, nargs@entry=2, args=, args@entry=0xffffb198) at /usr/src/debug/emacs-26.1-1/src/bytecode.c:629 #7 0x0000000100554187 in funcall_lambda (fun=4311658037, nargs=nargs@entry=2, arg_vector=arg_vector@entry=0xffffb198) at /usr/src/debug/emacs-26.1-1/src/eval.c:2970 #8 0x0000000100551a2b in Ffuncall (nargs=nargs@entry=3, args=0xffffb190) at /usr/src/debug/emacs-26.1-1/src/eval.c:2783 #9 0x0000000100553560 in Fapply (nargs=2, args=0xffffb2e0) at /usr/src/debug/emacs-26.1-1/src/eval.c:2389 #10 0x0000000100551ab0 in Ffuncall (nargs=, args=args@entry=0xffffb2d8) at /usr/src/debug/emacs-26.1-1/src/eval.c:2769 #11 0x0000000100588100 in exec_byte_code (bytestr=, vector=4294948333, maxdepth=, args_template=args_template@entry=514, nargs=, nargs@entry=2, args=, args@entry=0xffffb5f0) at /usr/src/debug/emacs-26.1-1/src/bytecode.c:629 #12 0x0000000100554187 in funcall_lambda (fun=4311084885, nargs=nargs@entry=2, arg_vector=arg_vector@entry=0xffffb5f0) at /usr/src/debug/emacs-26.1-1/src/eval.c:2970 #13 0x0000000100551a2b in Ffuncall (nargs=3, args=args@entry=0xffffb5e8) at /usr/src/debug/emacs-26.1-1/src/eval.c:2783 #14 0x0000000100588100 in exec_byte_code (bytestr=, vector=4294949125, maxdepth=, args_template=args_template@entry=2050, nargs=, nargs@entry=2, args=, args@entry=0xffffb908) at /usr/src/debug/emacs-26.1-1/src/bytecode.c:629 #15 0x0000000100554187 in funcall_lambda (fun=4302454965, nargs=nargs@entry=2, arg_vector=arg_vector@entry=0xffffb908) at /usr/src/debug/emacs-26.1-1/src/eval.c:2970 #16 0x0000000100551a2b in Ffuncall (nargs=3, args=args@entry=0xffffb900) at /usr/src/debug/emacs-26.1-1/src/eval.c:2783 #17 0x0000000100588100 in exec_byte_code (bytestr=, vector=4294949869, maxdepth=, args_template=args_template@entry=1030, nargs=, nargs@entry=1, args=, args@entry=0xffffbbf0) at /usr/src/debug/emacs-26.1-1/src/bytecode.c:629 #18 0x0000000100554187 in funcall_lambda (fun=4302453685, nargs=nargs@entry=1, arg_vector=arg_vector@entry=0xffffbbf0) at /usr/src/debug/emacs-26.1-1/src/eval.c:2970 #19 0x0000000100551a2b in Ffuncall (nargs=2, args=args@entry=0xffffbbe8) at /usr/src/debug/emacs-26.1-1/src/eval.c:2783 #20 0x0000000100588100 in exec_byte_code (bytestr=, vector=4294950549, maxdepth=, args_template=args_template@entry=2, nargs=, nargs@entry=0, args=, args@entry=0xffffbe98) at /usr/src/debug/emacs-26.1-1/src/bytecode.c:629 #21 0x0000000100554187 in funcall_lambda (fun=4302454245, nargs=nargs@entry=0, arg_vector=arg_vector@entry=0xffffbe98) at /usr/src/debug/emacs-26.1-1/src/eval.c:2970 #22 0x0000000100551a2b in Ffuncall (nargs=1, args=args@entry=0xffffbe90) at /usr/src/debug/emacs-26.1-1/src/eval.c:2783 #23 0x0000000100588100 in exec_byte_code (bytestr=, vector=4294951421, maxdepth=, args_template=args_template@entry=1030, nargs=, nargs@entry=1, args=, args@entry=0xffffc200) at /usr/src/debug/emacs-26.1-1/src/bytecode.c:629 #24 0x0000000100554187 in funcall_lambda (fun=4302432069, nargs=nargs@entry=1, arg_vector=arg_vector@entry=0xffffc200) at /usr/src/debug/emacs-26.1-1/src/eval.c:2970 #25 0x0000000100551a2b in Ffuncall (nargs=nargs@entry=2, args=args@entry=0xffffc1f8) at /usr/src/debug/emacs-26.1-1/src/eval.c:2783 #26 0x000000010054e423 in Ffuncall_interactively (nargs=2, args=0xffffc1f8) at /usr/src/debug/emacs-26.1-1/src/callint.c:252 ---Type to continue, or q to quit--- #27 0x0000000100551ab0 in Ffuncall (nargs=nargs@entry=10043408, args=0xffffc1f0, args@entry=0x100588100 ) at /usr/src/debug/emacs-26.1-1/src/eval.c:2769 #28 0x000000010054ed4f in Fcall_interactively (function=, record_flag=, keys=) at /usr/src/debug/emacs-26.1-1/src/callint.c:854 #29 0x0000000100551ab0 in Ffuncall (nargs=, args=args@entry=0xffffc448) at /usr/src/debug/emacs-26.1-1/src/eval.c:2769 #30 0x0000000100588100 in exec_byte_code (bytestr=, vector=4294952853, maxdepth=, args_template=args_template@entry=4102, nargs=, nargs@entry=1, args=, args@entry=0xffffc798) at /usr/src/debug/emacs-26.1-1/src/bytecode.c:629 #31 0x0000000100554187 in funcall_lambda (fun=4302011021, nargs=nargs@entry=1, arg_vector=arg_vector@entry=0xffffc798) at /usr/src/debug/emacs-26.1-1/src/eval.c:2970 #32 0x0000000100551a2b in Ffuncall (nargs=nargs@entry=2, args=args@entry=0xffffc790) at /usr/src/debug/emacs-26.1-1/src/eval.c:2783 #33 0x0000000100551b7f in call1 (fn=fn@entry=16080, arg1=) at /usr/src/debug/emacs-26.1-1/src/eval.c:2620 #34 0x00000001004ed24c in command_loop_1 () at /usr/src/debug/emacs-26.1-1/src/keyboard.c:1482 #35 0x0000000100550beb in internal_condition_case (bfun=bfun@entry=0x1004ecdf0 , handlers=handlers@entry=20928, hfun=hfun@entry=0x1004e3ca0 ) at /usr/src/debug/emacs-26.1-1/src/eval.c:1332 #36 0x00000001004de414 in command_loop_2 (ignore=) at /usr/src/debug/emacs-26.1-1/src/keyboard.c:1110 #37 0x0000000100550b5a in internal_catch (tag=tag@entry=50496, func=func@entry=0x1004de3f0 , arg=arg@entry=0) at /usr/src/debug/emacs-26.1-1/src/eval.c:1097 #38 0x00000001004de3a8 in command_loop () at /usr/src/debug/emacs-26.1-1/src/keyboard.c:1089 #39 0x00000001004e387d in recursive_edit_1 () at /usr/src/debug/emacs-26.1-1/src/keyboard.c:695 #40 0x00000001004e3bd4 in Frecursive_edit () at /usr/src/debug/emacs-26.1-1/src/keyboard.c:766 #41 0x00000001005e20d1 in main (argc=, argv=0xffffcc70) at /usr/src/debug/emacs-26.1-1/src/emacs.c:1717 BKCB؛[H\ܝΈY[K؛[\˚[BTNY[K٘\KB[][ێY[K˚[B[XܚXH[ΈY[K[ [XܚXK\[\CBB