If you happen to press Ctrl-C while GDB is running the Python unwinder
machinery, the Ctrl-C is swallowed by the Python unwinder machinery.
For example, with:
break foo
commands
> c
> end
and
while (1)
foo ();
and then let the inferior hit "foo" repeatedly, sometimes Ctrl-C
results in:
~~~
23 usleep (100);
Breakpoint 2, foo () at gdb.base/bp-cmds-continue-ctrl-c.c:23
23 usleep (100);
^C
Breakpoint 2, Python Exception <class 'KeyboardInterrupt'> <class 'KeyboardInterrupt'>:
foo () at gdb.base/bp-cmds-continue-ctrl-c.c:23
23 usleep (100);
Breakpoint 2, foo () at gdb.base/bp-cmds-continue-ctrl-c.c:23
23 usleep (100);
Breakpoint 2, foo () at gdb.base/bp-cmds-continue-ctrl-c.c:23
23 usleep (100);
~~~
Notice the Python exception above. The interesting thing here is that
GDB continues as if nothing happened, doesn't really stop and give
back control to the user. Instead, the Ctrl-C aborted the Python
unwinder sniffer and GDB moved on to just use another unwinder.
Fix this by translating a PyExc_KeyboardInterrupt back into a Quit
exception once back in GDB.
This was exposed by the new gdb.base/bp-cmds-continue-ctrl-c.exp
testcase added later in the series.
gdb/ChangeLog:
2017-11-16 Pedro Alves <palves@redhat.com>
* python/py-unwind.c (pyuw_sniffer): Translate
PyExc_KeyboardInterrupt to a GDB Quit exception.
9ccabccd15