bug#22012: 25.1.50; gdb broken by (json-string-format "doesn't start with `\"'!")

[martin rudalics]

Setting a breakpoint in gdb currently fails with a message like


Debugger entered--Lisp error: (json-string-format "doesn't start with `\"'!")
  signal(json-string-format ("doesn't start with `\"'!"))
  json-read-string()
  json-read-object()
  apply(json-read-object nil)
  json-read()
  json-read-object()
  apply(json-read-object nil)
  json-read()
  gdb-json-read-buffer("bkpt" "script")
  gdb-json-partial-output("bkpt" "script")
  gdb-breakpoints-list-handler-custom()
  gdb-breakpoints-list-handler()
  apply(gdb-breakpoints-list-handler nil)
  (save-current-buffer (set-buffer #<buffer *breakpoints of emacs.exe*>) (apply 
(quote gdb-breakpoints-list-handler) args))
  (with-current-buffer #<buffer *breakpoints of emacs.exe*> (apply (quote 
gdb-breakpoints-list-handler) args))
  (lambda (&rest args) (with-current-buffer #<buffer *breakpoints of 
emacs.exe*> (apply (quote gdb-breakpoints-list-handler) args)))()
  gdb-handle-reply(21)
  gdb-done-or-error("21" done 
"BreakpointTable={nr_rows=\"3\",nr_cols=\"6\",hdr=[{width=\"7\",alignment=\"-1\",col_name=\"number\",colhdr=\"Num\"},{width=\"14\",alignment=\"-1\",col_name=\"type\",colhdr=\"Type\"},{width=\"4\",alignment=\"-1\",col_name=\"disp\",colhdr=\"Disp\"},{width=\"3\",alignment=\"-1\",col_name=\"enabled\",colhdr=\"Enb\"},{width=\"10\",alignment=\"-1\",col_name=\"addr\",colhdr=\"Address\"},{width=\"40\",alignment=\"2\",col_name=\"what\",colhdr=\"What\"}],body=[bkpt={number=\"1\",type=\"breakpoint\",disp=\"keep\",enabled=\"y\",addr=\"0x01149c82\",func=\"terminate_due_to_signal\",file=\"../../src/emacs.c\",fullname=\"c:\\\\emacs-git\\\\trunk\\\\src\\\\emacs.c\",line=\"371\",times=\"0\",original-location=\"terminate_due_to_signal\"},bkpt={number=\"2\",type=\"breakpoint\",disp=\"del\",enabled=\"y\",addr=\"0x011819c2\",func=\"init_sys_modes\",file=\"../../src/sysdep.c\",fullname=\"c:\\\\emacs-git\\\\trunk\\\\src\\\\sysdep.c\",line=\"905\",times=\"0\",script={\"silen
t\",\"xgetptr globals.f_Vinitial_window_system\",\"xsymname $ptr\",\"xgetptr $symname\",\"set $tem = (struct Lisp_String *) $ptr\",\"set $tem = (char *) $tem->data\",\"if $tem[0] == 'x' && $tem[1] == '\\0'\",\"break 
x_error_quitter\",\"end\",\"continue\"},original-location=\"init_sys_modes\"},bkpt={number=\"3\",type=\"breakpoint\",disp=\"keep\",enabled=\"y\",addr=\"0x010c13e5\",func=\"Fsplit_window_internal\",file=\"../../src/window.c\",fullname=\"c:\\\\emacs-git\\\\trunk\\\\src\\\\window.c\",line=\"4253\",times=\"0\",original-location=\"window.c:4253\"}]}"
 t)
  gdb-done("21" "BreakpointTable={nr_rows=\"3\",nr_cols=\"6\",hdr=[{width=\"7\",alignment=\"-1\",col_name=\"number\",colhdr=\"Num\"},{width=\"14\",alignment=\"-1\",col_name=\"type\",colhdr=\"Type\"},{width=\"4\",alignment=\"-1\",col_name=\"disp\",colhdr=\"Disp\"},{width=\"3\",alignment=\"-1\",col_name=\"enabled\",colhdr=\"Enb\"},{width=\"10\",alignment=\"-1\",col_name=\"addr\",colhdr=\"Address\"},{width=\"40\",alignment=\"2\",col_name=\"what\",colhdr=\"What\"}],body=[bkpt={number=\"1\",type=\"breakpoint\",disp=\"keep\",enabled=\"y\",addr=\"0x01149c82\",func=\"terminate_due_to_signal\",file=\"../../src/emacs.c\",fullname=\"c:\\\\emacs-git\\\\trunk\\\\src\\\\emacs.c\",line=\"371\",times=\"0\",original-location=\"terminate_due_to_signal\"},bkpt={number=\"2\",type=\"breakpoint\",disp=\"del\",enabled=\"y\",addr=\"0x011819c2\",func=\"init_sys_modes\",file=\"../../src/sysdep.c\",fullname=\"c:\\\\emacs-git\\\\trunk\\\\src\\\\sysdep.c\",line=\"905\",times=\"0\",script={\"silent\",\"xgetptr 
globals.f_Vinitial_window_system\",\"xsymname $ptr\",\"xgetptr $symname\",\"set $tem = (struct Lisp_String *) $ptr\",\"set $tem = (char *) $tem->data\",\"if $tem[0] == 'x' && $tem[1] == '\\0'\",\"break x_error_quitter\",\"end\",\"continue\"},original-location=\"init_sys_modes\"},bkpt={number=\"3\",type=\"breakpoint\",disp=\"keep\",enabled=\"y\",addr=\"0x010c13e5\",func=\"Fsplit_window_internal\",file=\"../../src/window.c\",fullname=\"c:\\\\emacs-git\\\\trunk\\\\src\\\\window.c\",line=\"4253\",times=\"0\",original-location=\"window.c:4253\"}]}" t)
  gdbmi-bnf-incomplete-record-result("21" (gdb-done . progressive))
  #[0 "\302\300\301\242\"\207" ["21" ((gdb-done . progressive)) 
gdbmi-bnf-incomplete-record-result] 3]()
  gdbmi-bnf-result-and-async-record-impl()
  gdbmi-bnf-async-record()
  gdbmi-bnf-out-of-band-record()
  gdbmi-bnf-output()
  gud-gdbmi-marker-filter("19^error,msg=\"No registers.\"\n(gdb) \n20^done,threads=[]\n(gdb) 
\n21^done,BreakpointTable={nr_rows=\"3\",nr_cols=\"6\",hdr=[{width=\"7\",alignment=\"-1\",col_name=\"number\",colhdr=\"Num\"},{width=\"14\",alignment=\"-1\",col_name=\"type\",colhdr=\"Type\"},{width=\"4\",alignment=\"-1\",col_name=\"disp\",colhdr=\"Disp\"},{width=\"3\",alignment=\"-1\",col_name=\"enabled\",colhdr=\"Enb\"},{width=\"10\",alignment=\"-1\",col_name=\"addr\",colhdr=\"Address\"},{width=\"40\",alignment=\"2\",col_name=\"what\",colhdr=\"What\"}],body=[bkpt={number=\"1\",type=\"breakpoint\",disp=\"keep\",enabled=\"y\",addr=\"0x01149c82\",func=\"terminate_due_to_signal\",file=\"../../src/emacs.c\",fullname=\"c:\\\\emacs-git\\\\trunk\\\\src\\\\emacs.c\",line=\"371\",times=\"0\",original-location=\"terminate_due_to_signal\"},bkpt={number=\"2\",type=\"breakpoint\",disp=\"del\",enabled=\"y\",addr=\"0x011819c2\",func=\"init_sys_modes\",file=\"../../src/sysdep.c\",fullname=\"c:\\\\emacs-gi
t\\\\trunk\\\\src\\\\sysdep.c\",line=\"905\",times=\"0\",script={\"silent\",\"xgetptr globals.f_Vinitial_window_system\",\"xsymname $ptr\",\"xgetptr $symname\",\"set $tem = (struct Lisp_String *) $ptr\",\"set $tem = (char *) $tem->data\",\"if $tem[0] == 'x' && $tem[1] == '\\0'\",\"break 
x_error_quitter\",\"end\",\"continue\"},original-location=\"init_sys_modes\"},bkpt={number=\"3\",type=\"breakpoint\",disp=\"keep\",enabled=\"y\",addr=\"0x010c13e5\",func=\"Fsplit_window_internal\",file=\"../../src/window.c\",fullname=\"c:\\\\emacs-git\\\\trunk\\\\src\\\\window.c\",line=\"4253\",times=\"0\",original-location=\"window.c:4253\"}]}\n(gdb) \n")
  apply(gud-gdbmi-marker-filter "19^error,msg=\"No registers.\"\n(gdb) \n20^done,threads=[]\n(gdb) 
\n21^done,BreakpointTable={nr_rows=\"3\",nr_cols=\"6\",hdr=[{width=\"7\",alignment=\"-1\",col_name=\"number\",colhdr=\"Num\"},{width=\"14\",alignment=\"-1\",col_name=\"type\",colhdr=\"Type\"},{width=\"4\",alignment=\"-1\",col_name=\"disp\",colhdr=\"Disp\"},{width=\"3\",alignment=\"-1\",col_name=\"enabled\",colhdr=\"Enb\"},{width=\"10\",alignment=\"-1\",col_name=\"addr\",colhdr=\"Address\"},{width=\"40\",alignment=\"2\",col_name=\"what\",colhdr=\"What\"}],body=[bkpt={number=\"1\",type=\"breakpoint\",disp=\"keep\",enabled=\"y\",addr=\"0x01149c82\",func=\"terminate_due_to_signal\",file=\"../../src/emacs.c\",fullname=\"c:\\\\emacs-git\\\\trunk\\\\src\\\\emacs.c\",line=\"371\",times=\"0\",original-location=\"terminate_due_to_signal\"},bkpt={number=\"2\",type=\"breakpoint\",disp=\"del\",enabled=\"y\",addr=\"0x011819c2\",func=\"init_sys_modes\",file=\"../../src/sysdep.c\",fullname=\"c:\\\\em
acs-git\\\\trunk\\\\src\\\\sysdep.c\",line=\"905\",times=\"0\",script={\"silent\",\"xgetptr globals.f_Vinitial_window_system\",\"xsymname $ptr\",\"xgetptr $symname\",\"set $tem = (struct Lisp_String *) $ptr\",\"set $tem = (char *) $tem->data\",\"if $tem[0] == 'x' && $tem[1] == '\\0'\",\"break 
x_error_quitter\",\"end\",\"continue\"},original-location=\"init_sys_modes\"},bkpt={number=\"3\",type=\"breakpoint\",disp=\"keep\",enabled=\"y\",addr=\"0x010c13e5\",func=\"Fsplit_window_internal\",file=\"../../src/window.c\",fullname=\"c:\\\\emacs-git\\\\trunk\\\\src\\\\window.c\",line=\"4253\",times=\"0\",original-location=\"window.c:4253\"}]}\n(gdb) \n")
  gud-marker-filter("19^error,msg=\"No registers.\"\n(gdb) \n20^done,threads=[]\n(gdb) 
\n21^done,BreakpointTable={nr_rows=\"3\",nr_cols=\"6\",hdr=[{width=\"7\",alignment=\"-1\",col_name=\"number\",colhdr=\"Num\"},{width=\"14\",alignment=\"-1\",col_name=\"type\",colhdr=\"Type\"},{width=\"4\",alignment=\"-1\",col_name=\"disp\",colhdr=\"Disp\"},{width=\"3\",alignment=\"-1\",col_name=\"enabled\",colhdr=\"Enb\"},{width=\"10\",alignment=\"-1\",col_name=\"addr\",colhdr=\"Address\"},{width=\"40\",alignment=\"2\",col_name=\"what\",colhdr=\"What\"}],body=[bkpt={number=\"1\",type=\"breakpoint\",disp=\"keep\",enabled=\"y\",addr=\"0x01149c82\",func=\"terminate_due_to_signal\",file=\"../../src/emacs.c\",fullname=\"c:\\\\emacs-git\\\\trunk\\\\src\\\\emacs.c\",line=\"371\",times=\"0\",original-location=\"terminate_due_to_signal\"},bkpt={number=\"2\",type=\"breakpoint\",disp=\"del\",enabled=\"y\",addr=\"0x011819c2\",func=\"init_sys_modes\",file=\"../../src/sysdep.c\",fullname=\"c:\\\\emacs-git\\\\t
runk\\\\src\\\\sysdep.c\",line=\"905\",times=\"0\",script={\"silent\",\"xgetptr globals.f_Vinitial_window_system\",\"xsymname $ptr\",\"xgetptr $symname\",\"set $tem = (struct Lisp_String *) $ptr\",\"set $tem = (char *) $tem->data\",\"if $tem[0] == 'x' && $tem[1] == '\\0'\",\"break 
x_error_quitter\",\"end\",\"continue\"},original-location=\"init_sys_modes\"},bkpt={number=\"3\",type=\"breakpoint\",disp=\"keep\",enabled=\"y\",addr=\"0x010c13e5\",func=\"Fsplit_window_internal\",file=\"../../src/window.c\",fullname=\"c:\\\\emacs-git\\\\trunk\\\\src\\\\window.c\",line=\"4253\",times=\"0\",original-location=\"window.c:4253\"}]}\n(gdb) \n")
  gud-filter(#<process gud-emacs.exe> "19^error,msg=\"No registers.\"\n(gdb) \n20^done,threads=[]\n(gdb) 
\n21^done,BreakpointTable={nr_rows=\"3\",nr_cols=\"6\",hdr=[{width=\"7\",alignment=\"-1\",col_name=\"number\",colhdr=\"Num\"},{width=\"14\",alignment=\"-1\",col_name=\"type\",colhdr=\"Type\"},{width=\"4\",alignment=\"-1\",col_name=\"disp\",colhdr=\"Disp\"},{width=\"3\",alignment=\"-1\",col_name=\"enabled\",colhdr=\"Enb\"},{width=\"10\",alignment=\"-1\",col_name=\"addr\",colhdr=\"Address\"},{width=\"40\",alignment=\"2\",col_name=\"what\",colhdr=\"What\"}],body=[bkpt={number=\"1\",type=\"breakpoint\",disp=\"keep\",enabled=\"y\",addr=\"0x01149c82\",func=\"terminate_due_to_signal\",file=\"../../src/emacs.c\",fullname=\"c:\\\\emacs-git\\\\trunk\\\\src\\\\emacs.c\",line=\"371\",times=\"0\",original-location=\"terminate_due_to_signal\"},bkpt={number=\"2\",type=\"breakpoint\",disp=\"del\",enabled=\"y\",addr=\"0x011819c2\",func=\"init_sys_modes\",file=\"../../src/sysdep.c\",fullname=\"c:
\\\\emacs-git\\\\trunk\\\\src\\\\sysdep.c\",line=\"905\",times=\"0\",script={\"silent\",\"xgetptr globals.f_Vinitial_window_system\",\"xsymname $ptr\",\"xgetptr $symname\",\"set $tem = (struct Lisp_String *) $ptr\",\"set $tem = (char *) $tem->data\",\"if $tem[0] == 'x' && $tem[1] == '\\0'\",\"break 
x_error_quitter\",\"end\",\"continue\"},original-location=\"init_sys_modes\"},bkpt={number=\"3\",type=\"breakpoint\",disp=\"keep\",enabled=\"y\",addr=\"0x010c13e5\",func=\"Fsplit_window_internal\",file=\"../../src/window.c\",fullname=\"c:\\\\emacs-git\\\\trunk\\\\src\\\\window.c\",line=\"4253\",times=\"0\",original-location=\"window.c:4253\"}]}\n(gdb) \n")


In GNU Emacs 25.1.50.1 (i686-pc-mingw32)
 of 2015-11-24
Repository revision: e53b310fdecd7e3f130295b85b15289046d7a430
Windowing system distributor 'Microsoft Corp.', version 5.1.2600
Configured using:
 'configure --prefix=/c/emacs-git/ CFLAGS=-O3'

martin