[PATCH] Readline: Cleanup some warnings

[Pedro Alves]

On 02/01/2019 06:54 PM, Philippe Waroquiers wrote:
> 
> Switching to this readline version causes the following checks to fail:
> FAIL: gdb.gdb/selftest.exp: send SIGINT signal to child process (timeout)
> FAIL: gdb.gdb/selftest.exp: thread 1 (timeout)
> FAIL: gdb.gdb/selftest.exp: backtrace through signal handler (timeout)
> 
> Apart of that, no problem seen."

See the description in commit 4a11f2065906, which was later
reverted:

~~~
    Sync readline/ to version 7.0 alpha
...
    After the sync there is one testsuite regression, the test
    "signal SIGINT" in gdb.gdb/selftest.exp which now FAILs.  Previously,
    the readline 6.2 SIGINT handler would temporarily reinstall the
    underlying application's SIGINT handler and immediately re-raise SIGINT
    so that the orginal handler gets invoked.  But now (since readline 6.3)
    its SIGINT handler does not re-raise SIGINT or directly invoke the
    original handler; it now sets a flag marking that SIGINT was raised, and
    waits until readline explicitly has control to call the application's
    SIGINT handler.  Anyway, because SIGINT is no longer re-raised from
    within readline's SIGINT handler, doing "signal SIGINT" with a stopped
    inferior gdb process will no longer resume and then immediately stop the
    process (since there is no 2nd SIGINT to immediately catch).  Instead,
    the inferior gdb process will now just print "Quit" and continue to run.
    So with this commit, this particular test case is adjusted to reflect
    this change in behavior (we now have to send a 2nd SIGINT manually to
    stop it).
~~~

Thanks,
Pedro Alves