5 files changed, 176 insertions, 0 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 872838b2d1d..c3e3d210794 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,10 @@
+2013-10-18  Pedro Alves  <palves@redhat.com>
+
+	PR gdb/16062
+	* infrun.c (handle_inferior_event): Keep going if we got a random
+	signal we should not stop for, instead of falling through to the
+	step tests.
+
 2013-10-18  Yao Qi  <yao@codesourcery.com>
 
 	* c-varobj.c (cplus_number_of_children): Fix indentation.
diff --git a/gdb/infrun.c b/gdb/infrun.c
index 39c9cf3bb1c..b1f961163b1 100644
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -4715,6 +4715,17 @@ process_event_stop_test:
 	}
     }
 
+  if (ecs->random_signal)
+    {
+      if (debug_infrun)
+	 fprintf_unfiltered (gdb_stdlog,
+			     "infrun: random signal, keep going\n");
+
+      /* Signal not stepping related.  */
+      keep_going (ecs);
+      return;
+    }
+
   if (ecs->event_thread->control.step_resume_breakpoint)
     {
       if (debug_infrun)
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 77d9045e9d2..8e057f6d904 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2013-10-18  Pedro Alves  <palves@redhat.com>
+
+	PR gdb/16062
+	* gdb.threads/stepi-random-signal.c: New file.
+	* gdb.threads/stepi-random-signal.exp: New file.
+
 2013-10-17  Maciej W. Rozycki  <macro@codesourcery.com>
 
 	* gdb.mi/mi-breakpoint-changed.exp (test_insert_delete_modify):
diff --git a/gdb/testsuite/gdb.threads/stepi-random-signal.c b/gdb/testsuite/gdb.threads/stepi-random-signal.c
new file mode 100644
index 00000000000..2aec7f1bedf
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/stepi-random-signal.c
@@ -0,0 +1,48 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2013 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <pthread.h>
+#include <signal.h>
+#include <unistd.h>
+
+static pthread_t main_thread;
+
+static void *
+start (void *arg)
+{
+  /* A signal whose default action is ignore.  */
+  pthread_kill (main_thread, SIGCHLD);
+
+  while (1)
+    sleep (1); /* set break here */
+  return NULL;
+}
+
+int
+main (void)
+{
+  unsigned int counter = 1;
+  pthread_t thread;
+
+  main_thread = pthread_self ();
+  pthread_create (&thread, NULL, start, NULL);
+
+  while (counter != 0)
+    counter++; /* set break 2 here */
+
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.threads/stepi-random-signal.exp b/gdb/testsuite/gdb.threads/stepi-random-signal.exp
new file mode 100644
index 00000000000..5c12c6c4576
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/stepi-random-signal.exp
@@ -0,0 +1,104 @@
+# Copyright 2013 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+standard_testfile
+set executable ${testfile}
+
+if { [gdb_compile_pthreads \
+	  "${srcdir}/${subdir}/${srcfile}" \
+	  "${binfile}" \
+	  executable {debug}] != "" } {
+    untested "Couldn't compile test program."
+    return -1
+}
+
+clean_restart $executable
+
+# Start the second thread.
+if ![runto start] {
+    return -1
+}
+
+# Go back to the main thread, and leave it in the loop, where we're
+# reasonably sure we don't have 'conditional jmp $pc'-like
+# instructions.  We wouldn't be able to detect whether a stepi makes
+# progress over those.
+gdb_test_no_output "set scheduler-locking on"
+gdb_test "thread 1" "Switching to .*"
+gdb_breakpoint $srcfile:[gdb_get_line_number "set break 2 here"]
+gdb_continue_to_breakpoint "loop" ".* set break 2 here .*"
+
+# Now back to thread 2, and let it queue a signal in thread 1.
+gdb_test "thread 2" "Switching to .*"
+gdb_breakpoint $srcfile:[gdb_get_line_number "set break here"]
+gdb_continue_to_breakpoint "after pthread_kill" ".* set break here .*"
+
+# We're now ready to stepi thread 1.  It should immediately dequeue
+# the signal.
+gdb_test "thread 1" "Switching to .*" "thread 1 again"
+
+# No longer need these.
+delete_breakpoints
+
+# Turn on infrun debugging, so we can tell whether the signal is
+# really dequeued and that GDB sees it.
+gdb_test_no_output "set debug infrun 1"
+
+# Helper to extract the current PC.  PREFIX is used to make each call
+# have its own unique test name.
+
+proc get_pc { prefix } {
+    with_test_prefix "$prefix" {
+	return [get_hexadecimal_valueof "\$pc" ""]
+    }
+}
+
+set prev_addr [get_pc "before stepi"]
+if {$prev_addr == ""} {
+    return
+}
+
+# True if we saw the infrun path we want to test be exercised.
+set seen 0
+
+set test "stepi"
+if {[gdb_test_multiple "stepi" "$test" {
+    -re "infrun: random signal" {
+	set seen 1
+	exp_continue
+    }
+    -re "$gdb_prompt $" {
+    }
+}] != 0} {
+    return
+}
+
+if {$seen} {
+    pass "$test"
+} else {
+    fail "$test (no random signal)"
+}
+
+set addr [get_pc "after stepi"]
+if {$addr == ""} {
+    return
+}
+
+set test "stepi interfered by signal makes progress"
+if {$addr == $prev_addr} {
+    fail "$test"
+} else {
+    pass "$test"
+}