Make it easier to debug non-stop-fair-events.exp

If we enable infrun debug running this test, it quickly fails with a
full expect buffer.  That can be simply handled with a couple
exp_continues.  As it's annoying to hack this every time we need to
debug the test, this patch adds bits to enable debugging support
easily, with a one-line change.

And then, if any iteration of the test fails, we end up with a long
cascade of time outs.  Just bail out when we see the first fail.

gdb/testsuite/
2015-09-16  Pedro Alves  <palves@redhat.com>

	* gdb.threads/non-stop-fair-events.exp (gdb_test_no_anchor)
	(enable_debug): New procedures.
	(test): Use them.  Bail out if waiting for threads fails.
	(top level): Bail out if a test fails.

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index de503ac..ca2dfde 100644 (file)
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,10 @@
+2015-09-16  Pedro Alves  <palves@redhat.com>
+
+       * gdb.threads/non-stop-fair-events.exp (gdb_test_no_anchor)
+       (enable_debug): New procedures.
+       (test): Use them.  Bail out if waiting for threads fails.
+       (top level): Bail out if a test fails.
+
 2015-09-16  Yao Qi  <yao.qi@linaro.org>
 
        * gdb.asm/asm-source.exp: Set asm-arch for

diff --git a/gdb/testsuite/gdb.threads/non-stop-fair-events.exp b/gdb/testsuite/gdb.threads/non-stop-fair-events.exp
index e2d3f7d..37f5bcb 100644 (file)
--- a/gdb/testsuite/gdb.threads/non-stop-fair-events.exp
+++ b/gdb/testsuite/gdb.threads/non-stop-fair-events.exp
@@ -98,6 +98,29 @@ proc restart {} {
     delete_breakpoints
 }
 
+# Run command and wait for the prompt, without end anchor.
+
+proc gdb_test_no_anchor {cmd} {
+    global gdb_prompt
+
+    gdb_test_multiple $cmd $cmd {
+       -re "$gdb_prompt " {
+           pass $cmd
+       }
+    }
+}
+
+# Enable/disable debugging.
+
+proc enable_debug {enable} {
+
+    # Comment out to debug problems with the test.
+    return
+
+    gdb_test_no_anchor "set debug infrun $enable"
+    gdb_test_no_anchor "set debug displaced $enable"
+}
+
 # The test proper.  SIGNAL_THREAD is the thread that has been elected
 # to receive the SIGUSR1 signal.
 
@@ -126,30 +149,55 @@ proc test {signal_thread} {
 
        # Let the main thread queue the signal.
        gdb_breakpoint "loop_broke"
+
+       enable_debug 1
+
+       set saw_continuing 0
        set test "continue &"
        gdb_test_multiple $test $test {
-           -re "Continuing.\r\n$gdb_prompt " {
-               pass $test
+           -re "Continuing.\r\n" {
+               set saw_continuing 1
+               exp_continue
+           }
+           -re "$gdb_prompt " {
+               gdb_assert $saw_continuing $test
+           }
+           -re "infrun:" {
+               exp_continue
            }
        }
 
+       set gotit 0
+
        # Wait for all threads to finish their steps, and for the main
        # thread to hit the breakpoint.
        for {set i 1} { $i <= $NUM_THREADS } { incr i } {
            set test "thread $i broke out of loop"
+           set gotit 0
            gdb_test_multiple "" $test {
                -re "loop_broke" {
                    # The prompt was already matched in the "continue
                    # &" test above.  We're now consuming asynchronous
                    # output that comes after the prompt.
+                   set gotit 1
                    pass $test
                }
+               -re "infrun:" {
+                   exp_continue
+               }
+           }
+           if {!$gotit} {
+               break
            }
        }
 
+       enable_debug 0
+
        # It's helpful to have this in the log if the test ever
        # happens to fail.
        gdb_test "info threads"
+
+       return $gotit
     }
 }
 
@@ -158,5 +206,8 @@ proc test {signal_thread} {
 # with lowest kernel thread ID.  So test once with the signal pending
 # in each thread, except the main thread.
 for {set i 2} { $i <= $NUM_THREADS } { incr i } {
-    test $i
+    if {![test $i]} {
+       # Avoid cascading timeouts, and bail out.
+       return
+    }
 }