[RFA 1/2] PR gdb/20604 - fix "quit" when an invalid expression is used

[Pedro Alves]

Hi Tom, the gdb code looks fine.  Some comments on the test.

On 09/14/2016 11:59 PM, Tom Tromey wrote:

> +# Check the "quit" command.
> +
> +clean_restart
> +
> +# Test that a syntax error causes quit to abort.
> +# Regression test for PR gdb/20604.
> +gdb_test "quit()" "A syntax error in expression, near .*" \
> +    "quit with syntax error"
> +
> +# Test that an expression can be used to set the error code.
> +send_gdb "quit 22+1\n"
> +set result [wait -i $gdb_spawn_id]
> +verbose $result
> +if {[lindex $result 2] == 0 && [lindex $result 3] == 23} {

Not sure getting back the exit status works universally with 
remote-host testing.  ISTR we're not guaranteed to get back an
exit status on all connection types (may get back an ssh/rsh status
instead).  Also, the board may need to tear down more
than just gdb.

Could you try the new test with --host_board=local-remote-host.exp?  
That should cover at least remote ssh testing, which is what
most people use nowadays, anyway.  I'd be happy with that.

> +    pass "quit with expression"
> +} else {
> +    fail "quit with expression"
> +}
> +close $gdb_spawn_id

I suspect that this may be breaking non-parallel-mode testing
(e.g., runtest directly instead of make check), since it leaves 
$gdb_spawn_id set.

Maybe just calling clear_gdb_spawn_id at the end is all that's
necessary?

(I mildly wonder whether making this a gdb.gdb self test would be a good
idea.  I.e., the inferior gdb's exit would be caught by the
superior gdb as a normal exit.  OTOH, that'd make the test
heavier.)

Thanks,
Pedro Alves