如何在emac gdb中设置undo-outer-limit

Question

我在emacs 24.3中使用了gdb 7.6的撤消功能，并收到了以下警告。它建议我设置`undo-outer-limit＆＃39;是一个更大的价值。我该如何将变量设置为正确的值？ emacs支持多大？

Warning (undo): Buffer `*gud-foo*' undo info was 13351087 bytes long.
The undo info was discarded because it exceeded `undo-outer-limit'.

This is normal if you executed a command that made a huge change
to the buffer.  In that case, to prevent similar problems in the
future, set `undo-outer-limit' to a value that is large enough to
cover the maximum size of normal changes you expect a single
command to make, but not so large that it might exceed the
maximum memory allotted to Emacs.

If you did not execute any such command, the situation is
probably due to a bug and you should report it.

You can disable the popping up of this buffer by adding the entry
(undo discard-info) to the user option `warning-suppress-types',
which is defined in the `warnings' library.

Answer 1

  

我使用了gdb 7.6的撤消功能，并收到了以下警告

这是来自Emacs的警告。它与GDB没有没有。