gdb-switch-reasons

gdb-switch-reasons is a variable defined in `gdb-mi.el'.
Its value is

t

Documentation:
List of stop reasons for which Emacs should switch thread.
When t, switch to stopped thread no matter what the reason was.
When nil, never switch to stopped thread automatically.

This setting is used in non-stop mode only. In all-stop mode,
Emacs always switches to the thread which caused the stop.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 23.2 of Emacs.