Hello, when debugging c-programs (the special program does not matter) with gud/gdb the prompt "(gdb)" is missing after the execution of the "start" command. This also happens with other commands such as "next". Also variable values and outputs are not correctly updated. I do not have this problem under linux. There was already a similar problem with the update of the gdb-interface: https://www.cygwin.com/ml/cygwin/2015-06/msg00277.html That thread has a dead end. If one sets gdbmi-debug-mode to t one gets log messages in the Message buffer. I guess from these messages that the gdb interface gets incomplete output from gdb. (Maybe a timing-issue?) Reconstruction of the problem: Create a small c-file "test.c" e.g.: ----------8<---------- #include int main() { int i=0; i=1; printf("%d\n",i); i=2; printf("%d\n",i); i=3; printf("%d\n",i); return 0; } /* Local Variables: compile-command: "gcc -g test.c -o a.exe;" End: */ ---------->8---------- In the following all user input is marked with '>' at the line beginning: >emacs -Q test.c >M-x gdb-enable-debug >M-: (setq gdbmi-debug-mode t) >M-x gdb >start There follows the output of emacs after that input sequence. Note that there is no final "(gdb)" prompt! ----------8<---------- Current directory is /temp/ GNU gdb (GDB) (Cygwin 7.10.1-1) 7.10.1 Copyright (C) 2015 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "x86_64-pc-cygwin". Type "show configuration" for configuration details. For bug reporting instructions, please see: . Find the GDB manual and other documentation resources online at: . For help, type "help". Type "apropos word" to search for commands related to "word"... Reading symbols from a.exe...done. (gdb) start The target does not support running in non-stop mode. ---------->8---------- In the following output of the Message buffer note the lines "gdbmi-bnf-incomplete-record-result, aborting: incomplete stream"! >C-x b *Messages* ----------8<---------- For information about GNU Emacs and the GNU system, type C-h C-a. Gdb-Enable-Debug mode enabled t gdb-input: 1-inferior-tty-set /dev/pty7 gdb-input: 2-gdb-set height 0 gdb-input: 3-gdb-set non-stop 1 gdb-input: 4-enable-pretty-printing gdb-input: 5-file-list-exec-source-files gdb-input: 6-file-list-exec-source-file gdb-input: 7-gdb-show prompt gdb-input: 8-stack-info-frame gdb-input: 9-thread-info gdb-input: 10-break-list gdb-input: 11-thread-info gdb-input: 12-break-list gdbmi-bnf-result-record: =thread-group-added, gdbmi-bnf-incomplete-record-result: id="i1" gdbmi-bnf-stream-record: ~"GNU gdb (GDB) (Cygwin 7.10.1-1) 7.10.1\n" gdbmi-bnf-stream-record: ~"Copyright (C) 2015 Free Software Foundation, Inc.\n" gud-gdbmi-marker-filter, unparsed string: ~"License GPLv3+: GNU GPL version 3 or later \nThis is free software: you are free to change an gdbmi-bnf-stream-record: ~"License GPLv3+: GNU GPL version 3 or later \nThis is free software: you are free to change and redistribute it.\nThere is NO WARRANTY, to the extent permitted by law. Type \"show copying\"\nand \"show warranty\" for details.\n" gdbmi-bnf-stream-record: ~"This GDB was configured as \"x86_64-pc-cygwin\".\nType \"show configuration\" for configuration details." gud-gdbmi-marker-filter, unparsed string: ~"\nFor bug gdbmi-bnf-stream-record: ~"\nFor bug reporting instructions, please see:\n" gdbmi-bnf-stream-record: ~".\n" gdbmi-bnf-stream-record: ~"Find the GDB manual and other documentation resources online at:\n.\n" gdbmi-bnf-stream-record: ~"For help, type \"help\".\n" gud-gdbmi-marker-filter, unparsed string: ~"Type \"apropos wor gdbmi-bnf-stream-record: ~"Type \"apropos word\" to search for commands related to \"word\"...\n" gdbmi-bnf-result-record: =cmd-param-changed, gdbmi-bnf-incomplete-record-result: param="extension-language",value=".y" gdbmi-bnf-stream-record: ~"Reading symbols from a.exe..." gdbmi-bnf-stream-record: ~"done.\n" gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 1^done gdb-input: 13-thread-info gdb-input: 14-break-list gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 2^done gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 3^done gdb-input: 15-gdb-set target-async 1 gdb-input: 16-list-target-features gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 4^done gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 5^done, gdbmi-bnf-incomplete-record-result: files=[{file="test.c",fullname="/cygdrive/c/temp/test.c"},{file="/usr/src/debug/gcc-5.3.0-5/libgcc/libgcc2.c",fullname="/usr/src/debug/gcc-5.3.0-5/libgcc/libgcc2.c"},{file="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/cygwin_attach_dll.c",fullnam gdbmi-bnf-incomplete-record-result, aborting: incomplete stream gdbmi-bnf-incomplete-record-result: e="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/cygwin_attach_dll.c"},{file="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/pseudo-reloc-dummy.c",fullname="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/pseudo-reloc-dummy.c"},{file="/usr/src/debug/cyg gdbmi-bnf-incomplete-record-result, aborting: incomplete stream gdbmi-bnf-incomplete-record-result: win-2.5.1-1/winsup/cygwin/lib/dll_main.cc",fullname="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/dll_main.cc"},{file="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/dll_entry.c",fullname="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/dll_entry.c"},{ gdbmi-bnf-incomplete-record-result, aborting: incomplete stream gdbmi-bnf-incomplete-record-result: file="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/_cygwin_crt0_common.cc",fullname="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/_cygwin_crt0_common.cc"},{file="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/premain3.c",fullname="/usr/src/debug/cyg gdbmi-bnf-incomplete-record-result, aborting: incomplete stream gdbmi-bnf-incomplete-record-result: win-2.5.1-1/winsup/cygwin/lib/premain3.c"},{file="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/premain2.c",fullname="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/premain2.c"},{file="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/premain1.c",fullname gdbmi-bnf-incomplete-record-result, aborting: incomplete stream gdbmi-bnf-incomplete-record-result: ="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/premain1.c"},{file="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/premain0.c",fullname="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/premain0.c"},{file="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/ gdbmi-bnf-incomplete-record-result, aborting: incomplete stream gdbmi-bnf-incomplete-record-result: cygwin_crt0.c",fullname="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/cygwin_crt0.c"},{file="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/crt0.c",fullname="/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/crt0.c"}] gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 6^done, gdbmi-bnf-incomplete-record-result: line="1",file="test.c",fullnam gdbmi-bnf-incomplete-record-result, aborting: incomplete stream gdbmi-bnf-incomplete-record-result: e="/cygdrive/c/temp/test.c",macro-info="0" gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 7^done, gdbmi-bnf-incomplete-record-result: value="(gdb) " gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 8^error, gdbmi-bnf-incomplete-record-result: msg="No registers." gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 9^done, gdbmi-bnf-incomplete-record-result: threads=[] gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 10^done, gdbmi-bnf-incomplete-record-result: BreakpointTable={nr_rows="0",nr_cols="6",hdr=[{width="7",alignment="-1",col_name="number",colhdr="Num"},{widt gdbmi-bnf-incomplete-record-result, aborting: incomplete stream gdbmi-bnf-incomplete-record-result: h="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", gdbmi-bnf-incomplete-record-result, aborting: incomplete stream gdbmi-bnf-incomplete-record-result: col_name="what",colhdr="What"}],body=[]} gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 11^done, gdbmi-bnf-incomplete-record-result: threads=[] gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 12^done, gdbmi-bnf-incomplete-record-result: BreakpointTable={nr_rows="0",nr_cols="6",hdr=[{width="7",alignment="-1",col_name="number",colhdr="Num"},{width="14",alignment="-1",col_name="type",colhdr="Type"},{width="4",a gdbmi-bnf-incomplete-record-result, aborting: incomplete stream gdbmi-bnf-incomplete-record-result: lignment="-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=[]} gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 13^done, gdbmi-bnf-incomplete-record-result: threads=[ gdbmi-bnf-incomplete-record-result, aborting: incomplete stream gdbmi-bnf-incomplete-record-result: ] gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 14^done, gdbmi-bnf-incomplete-record-result: BreakpointTable={nr_rows="0",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 gdbmi-bnf-incomplete-record-result, aborting: incomplete stream gdbmi-bnf-incomplete-record-result: _name="enabled",colhdr="Enb"},{width="10",alignment="-1",col_name="addr",colhdr="Address"},{width="40",alignment="2",col_name="what",colhdr="What"}],body=[]} gdb-input: 17-stack-info-frame gdb-input: 18-thread-info gdb-input: 19-break-list gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 15^done gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 16^done, gdbmi-bnf-incomplete-record-result: features=[] Target doesn't support non-stop mode. Turning it off. gdb-input: 20-gdb-set non-stop 0 gdbmi-bnf-gdb-prompt: (gdb) gud-gdbmi-marker-filter, unparsed string: &"The target does not support running in non-stop gdbmi-bnf-stream-record: &"The target does not support running in non-stop mode.\n" gdbmi-bnf-result-record: ^error, gdbmi-bnf-incomplete-record-result: msg="The target does not support running in non-stop mode." The target does not support running in non-stop mode. gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 17^error, gdbmi-bnf-incomplete-record-result: msg="No registers." gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 18^done, gdbmi-bnf-incomplete-record-result: threads=[] gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 19^done, gdbmi-bnf-incomplete-record-result: BreakpointTable={nr_rows="0",nr_cols="6",hdr=[{width="7",alignment="-1",col_name="number",colhdr="Num" gdbmi-bnf-incomplete-record-result, aborting: incomplete stream gdbmi-bnf-incomplete-record-result: },{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",alignme gdbmi-bnf-incomplete-record-result, aborting: incomplete stream gdbmi-bnf-incomplete-record-result: nt="2",col_name="what",colhdr="What"}],body=[]} gdbmi-bnf-gdb-prompt: (gdb) gdbmi-bnf-result-record: 20^done gdbmi-bnf-gdb-prompt: (gdb) ---------->8---------- Last but not least the content of the debug variable gdb-debug-log. This is a queque. The most recent cell is at the beginning. Note the crippled received input string at the beginning! >C-h v gdb-debug-log ----------8<---------- Value: ((recv . "nt=\"2\",col_name=\"what\",colhdr=\"What\"}],body=[]}\n(gdb) \n20^done\n(gdb) \n") (recv . "},{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\",alignme") (recv . " mode.\\n\"\n^error,msg=\"The target does not support running in non-stop mode.\"\n(gdb) \n17^error,msg=\"No registers.\"\n(gdb) \n18^done,threads=[]\n(gdb) \n19^done,BreakpointTable={nr_rows=\"0\",nr_cols=\"6\",hdr=[{width=\"7\",alignment=\"-1\",col_name=\"number\",colhdr=\"Num\"") (send-item "20-gdb-set non-stop 0" ignore) (send-item "19-break-list" (lambda (&rest args) (with-current-buffer # (apply 'gdb-breakpoints-list-handler args)))) (send-item "18-thread-info" (lambda (&rest args) (with-current-buffer # (apply 'gdb-thread-list-handler args)))) (send-item "17-stack-info-frame" gdb-frame-handler) (recv . "_name=\"enabled\",colhdr=\"Enb\"},{width=\"10\",alignment=\"-1\",col_name=\"addr\",colhdr=\"Address\"},{width=\"40\",alignment=\"2\",col_name=\"what\",colhdr=\"What\"}],body=[]}\n(gdb) \n15^done\n(gdb) \n16^done,features=[]\n(gdb) \n&\"The target does not support running in non-stop") (recv . "14^done,BreakpointTable={nr_rows=\"0\",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") (mi-send . #("-interpreter-exec console \"start \"\n" 27 32 (fontified t))) (recv . "]\n(gdb) \n") (recv . "lignment=\"-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=[]}\n(gdb) \n13^done,threads=[") (recv . "col_name=\"what\",colhdr=\"What\"}],body=[]}\n(gdb) \n11^done,threads=[]\n(gdb) \n12^done,BreakpointTable={nr_rows=\"0\",nr_cols=\"6\",hdr=[{width=\"7\",alignment=\"-1\",col_name=\"number\",colhdr=\"Num\"},{width=\"14\",alignment=\"-1\",col_name=\"type\",colhdr=\"Type\"},{width=\"4\",a") (recv . "h=\"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\",") (recv . "e=\"/cygdrive/c/temp/test.c\",macro-info=\"0\"\n(gdb) \n7^done,value=\"(gdb) \"\n(gdb) \n8^error,msg=\"No registers.\"\n(gdb) \n9^done,threads=[]\n(gdb) \n10^done,BreakpointTable={nr_rows=\"0\",nr_cols=\"6\",hdr=[{width=\"7\",alignment=\"-1\",col_name=\"number\",colhdr=\"Num\"},{widt") (recv . "cygwin_crt0.c\",fullname=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/cygwin_crt0.c\"},{file=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/crt0.c\",fullname=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/crt0.c\"}]\n(gdb) \n6^done,line=\"1\",file=\"test.c\",fullnam") (recv . "=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/premain1.c\"},{file=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/premain0.c\",fullname=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/premain0.c\"},{file=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/") (recv . "win-2.5.1-1/winsup/cygwin/lib/premain3.c\"},{file=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/premain2.c\",fullname=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/premain2.c\"},{file=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/premain1.c\",fullname") (recv . "file=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/_cygwin_crt0_common.cc\",fullname=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/_cygwin_crt0_common.cc\"},{file=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/premain3.c\",fullname=\"/usr/src/debug/cyg") (recv . "win-2.5.1-1/winsup/cygwin/lib/dll_main.cc\",fullname=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/dll_main.cc\"},{file=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/dll_entry.c\",fullname=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/dll_entry.c\"},{") (recv . "e=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/cygwin_attach_dll.c\"},{file=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/pseudo-reloc-dummy.c\",fullname=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/pseudo-reloc-dummy.c\"},{file=\"/usr/src/debug/cyg") (recv . "5^done,files=[{file=\"test.c\",fullname=\"/cygdrive/c/temp/test.c\"},{file=\"/usr/src/debug/gcc-5.3.0-5/libgcc/libgcc2.c\",fullname=\"/usr/src/debug/gcc-5.3.0-5/libgcc/libgcc2.c\"},{file=\"/usr/src/debug/cygwin-2.5.1-1/winsup/cygwin/lib/cygwin_attach_dll.c\",fullnam") (send-item "16-list-target-features" gdb-check-target-async) (send-item "15-gdb-set target-async 1" ignore) (recv . "2^done\n(gdb) \n3^done\n(gdb) \n4^done\n(gdb) \n") (send-item "14-break-list" (lambda (&rest args) (with-current-buffer # (apply 'gdb-breakpoints-list-handler args)))) (send-item "13-thread-info" (lambda (&rest args) (with-current-buffer # (apply 'gdb-thread-list-handler args)))) (recv . "d\\\" to search for commands related to \\\"word\\\"...\\n\"\n=cmd-param-changed,param=\"extension-language\",value=\".y\"\n~\"Reading symbols from a.exe...\"\n~\"done.\\n\"\n(gdb) \n1^done\n(gdb) \n") (recv . "reporting instructions, please see:\\n\"\n~\".\\n\"\n~\"Find the GDB manual and other documentation resources online at:\\n.\\n\"\n~\"For help, type \\\"help\\\".\\n\"\n~\"Type \\\"apropos wor") (recv . "d redistribute it.\\nThere is NO WARRANTY, to the extent permitted by law. Type \\\"show copying\\\"\\nand \\\"show warranty\\\" for details.\\n\"\n~\"This GDB was configured as \\\"x86_64-pc-cygwin\\\".\\nType \\\"show configuration\\\" for configuration details.\"\n~\"\\nFor bug ") (recv . "=thread-group-added,id=\"i1\"\n~\"GNU gdb (GDB) (Cygwin 7.10.1-1) 7.10.1\\n\"\n~\"Copyright (C) 2015 Free Software Foundation, Inc.\\n\"\n~\"License GPLv3+: GNU GPL version 3 or later \\nThis is free software: you are free to change an") (send-item "12-break-list" (lambda (&rest args) (with-current-buffer # (apply 'gdb-breakpoints-list-handler args)))) (send-item "11-thread-info" (lambda (&rest args) (with-current-buffer # (apply 'gdb-thread-list-handler args)))) (send-item "10-break-list" (lambda (&rest args) (with-current-buffer # (apply 'gdb-breakpoints-list-handler args)))) (send-item "9-thread-info" (lambda (&rest args) (with-current-buffer # (apply 'gdb-thread-list-handler args)))) (send-item "8-stack-info-frame" gdb-frame-handler) (send-item "7-gdb-show prompt" gdb-get-prompt) (send-item "6-file-list-exec-source-file" gdb-get-source-file) (send-item "5-file-list-exec-source-files" gdb-get-source-file-list) (send-item "4-enable-pretty-printing" ignore) (send-item "3-gdb-set non-stop 1" gdb-non-stop-handler) (send-item "2-gdb-set height 0" ignore) (send-item "1-inferior-tty-set /dev/pty7" ignore)) ---------->8---------- That is about as far as I get with my limited time frame. I would be extremely pleased if someone with more insider knowledge of gdbmi and cygwin-processes could take on the challange! I need the debugger for production and the missing update is rather disturbing. Best regards, Tobias