Re: [PATCH 4/6] testsuite: Don't use expect_background to reap gdbserver

[Yao Qi <qiyaoltc@gmail.com>]

Pedro Alves <palves@redhat.com> writes:

> +proc gdb_exit {} {
> +    global gdb_spawn_id server_spawn_id
> +    global gdb_prompt
> +
> +    if {[info exists gdb_spawn_id] && [info exists server_spawn_id]} {
> +	send_gdb "monitor exit\n";
> +	gdb_expect {
> +	    -re "$gdb_prompt $" {
> +		exp_continue
> +	    }
> +	    -i "$server_spawn_id" eof {
> +		wait -i $expect_out(spawn_id)
> +		unset server_spawn_id
> +	    }
> +	}
> +    }

Do we need to catch exception here?

I see the error when I run gdb-sigterm.exp with native-gdbserver
on x86_64-linux.

infrun: prepare_to_wait^M
Cannot execute this command while the target is running.^M
Use the "interrupt" command to stop the target^M
and then try again.^M
gdb.base/gdb-sigterm.exp: expect eof #0: got eof
gdb.base/gdb-sigterm.exp: expect eof #0: stepped 12 times
ERROR OCCURED: : spawn id exp8 not open
    while executing
"expect {
-i exp8 -timeout 10
            -re "$gdb_prompt $" {
                exp_continue
            }
            -i "$server_spawn_id" eof {
                wait -i $expect_out(spawn_id)
                unse..."
    ("uplevel" body line 1)
    invoked from within

In gdb-sigterm.exp, SIGTERM is sent to GDB and it exits.  However,
Dejagnu or tcl doesn't know this.


> +    close_gdbserver
> +
> +    gdbserver_orig_gdb_exit
> +}

This error terminates the whole testing, so the following tests are
not run.

I wrap the send_gdb and gdb_expect statement above by "catch",
testing looks fine, although error messages are still shown in the
console and gdb.log.

-- 
Yao (齐尧)

From: Yao Qi <yao.qi@linaro.org>
Date: Mon, 13 Apr 2015 12:36:56 +0100
Subject: [PATCH] Catch exception in lib/gdbserver-support.exp:gdb_exit

I see the error when I run gdb-sigterm.exp with native-gdbserver
on x86_64-linux.

infrun: prepare_to_wait^M
Cannot execute this command while the target is running.^M
Use the "interrupt" command to stop the target^M
and then try again.^M
gdb.base/gdb-sigterm.exp: expect eof #0: got eof
gdb.base/gdb-sigterm.exp: expect eof #0: stepped 12 times
ERROR OCCURED: : spawn id exp8 not open
    while executing
"expect {
-i exp8 -timeout 10
            -re "$gdb_prompt $" {
                exp_continue
            }
            -i "$server_spawn_id" eof {
                wait -i $expect_out(spawn_id)
                unse..."
    ("uplevel" body line 1)
    invoked from within

In gdb-sigterm.exp, SIGTERM is sent to GDB and it exits.  However,
Dejagnu or tcl doesn't know this.

This patch is to catch the exception, but error messages are still
shown in the console and gdb.log.

gdb/testsuite:

2015-04-13  Yao Qi  <yao.qi@linaro.org>

	* lib/gdbserver-support.exp (gdb_exit): Catch exception.

diff --git a/gdb/testsuite/lib/gdbserver-support.exp b/gdb/testsuite/lib/gdbserver-support.exp
index 53843b8..8d4858a 100644
--- a/gdb/testsuite/lib/gdbserver-support.exp
+++ b/gdb/testsuite/lib/gdbserver-support.exp
@@ -353,15 +353,20 @@ proc gdb_exit {} {
     global gdb_prompt
 
     if {[info exists gdb_spawn_id] && [info exists server_spawn_id]} {
-	send_gdb "monitor exit\n";
-	gdb_expect {
-	    -re "$gdb_prompt $" {
-		exp_continue
-	    }
-	    -i "$server_spawn_id" eof {
-		wait -i $expect_out(spawn_id)
-		unset server_spawn_id
-		unset inferior_spawn_id
+	# GDB may be terminated in an expected way or an unexpected way,
+	# but DejaGNU doesn't know that, so gdb_spawn_id isn't unset.
+	# Catch the exceptions.
+	catch {
+	    send_gdb "monitor exit\n";
+	    gdb_expect {
+		-re "$gdb_prompt $" {
+		    exp_continue
+		}
+		-i "$server_spawn_id" eof {
+		    wait -i $expect_out(spawn_id)
+		    unset server_spawn_id
+		    unset inferior_spawn_id
+		}
 	    }
 	}
     }