Using gdb -i=mi integration in emacs 24

Question

I'm checking out a segfault in one of our apps. A short time after starting the app, the main gdb status bar changes to:

(Debugger:run [signal-received])

A (gdb) prompt appears but the contents of all other windows remain unchanged (empty). Typing anything at the prompt does nothing - gdb appears to be hanging. Running the same steps on the command line results in the expected output from gdb with a complete and correct backtrace.

This is my first time debugging with the -i=mi integration between emacs and gdb. I'm using emacs 24.2 and gdb 7.5.

Are there any suggestions on how I can debug this further?

Is it possible to reduce the level of integration? Would that allow me to determine which area is causing the problem?

A final point is that the initial loading of the app takes around 70s compared with around 3s from the command line.

Stefan · Answer 1 · 2016-06-30T22:42:47.487

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You can use M-x gud-gdb to use the old gud mode (i.e. without the mi interaction). Less fancy but more reliable.

edited Jun 30 '16 at 22:42

answered Dec 20 '12 at 02:18

Stefan

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Thanks for the response. Did you mean 'without' the `mi` interaction? Maybe I'm doing something wrong, but the `gud-gdb` mode appears to be quite a jump back from '--annotate=3' support. Particularly the link between debug location and the source. Is there a way to address this? When it stops at a break point I get `^Z^Z/home/richard/.../main.cpp:235:5568:beg:0x80a17d3`. – Richard Corden Dec 20 '12 at 08:59
You shouldn't see things like `^Z^Z/home/richard/.../main.cpp:235:5568:beg:0x80a17d3`, so I suspect GDB is not in the right annotation mode. For `gud-gdb`, GDB should be started as `gdb --fullname ...` IIUC. – Stefan Dec 20 '12 at 14:14

score 8 · Accepted Answer · answered Feb 19 '13 at 23:30

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Load time can be reduced by setting gdb-create-source-file-list to nil (use customize). See the documentation for what this does and why it substantially increases load times in some instances.

answered Feb 19 '13 at 23:30

Alastair

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Spot on. I'd actually downgraded to 23 because of this - so hopefully now I can stick with the latest version. – Richard Corden Feb 21 '13 at 20:28

Richard Corden · Answer 3 · 2012-12-20T10:32:21.963

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It appears that gdb-ui from emacs 23 will still work in emacs 24:

Find a copy of gdb-ui (In my case gdb-ui.el.gz and gdb-ui.elc from a backup)
Place these into a directory (I have added ~/emacs-modes)

Then add the following to your .emacs:

(add-to-list 'load-path "~/emacs-modes")
(require 'gdb-ui)

Running gdb will now use the old --annotate=3 mode rather than -i=mi.

edited Dec 20 '12 at 10:32

answered Dec 20 '12 at 09:29

Richard Corden

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Using gdb -i=mi integration in emacs 24

3 Answers3