Index: infrun.c
===================================================================
RCS file: /cvs/src/src/gdb/infrun.c,v
retrieving revision 1.590
diff -u -p -r1.590 infrun.c
--- infrun.c	3 Sep 2013 17:22:45 -0000	1.590
+++ infrun.c	16 Sep 2013 08:06:02 -0000
@@ -3038,7 +3038,8 @@ adjust_pc_after_break (struct execution_
       if (singlestep_breakpoints_inserted_p
 	  || !ptid_equal (ecs->ptid, inferior_ptid)
 	  || !currently_stepping (ecs->event_thread)
-	  || ecs->event_thread->prev_pc == breakpoint_pc)
+	  || (ecs->event_thread->prev_pc == breakpoint_pc
+	      && software_breakpoint_inserted_here_p (aspace, breakpoint_pc)))
 	regcache_write_pc (regcache, breakpoint_pc);
 
       do_cleanups (old_cleanups);
Index: testsuite/gdb.base/pr15520.cc
===================================================================
RCS file: testsuite/gdb.base/pr15520.cc
diff -N testsuite/gdb.base/pr15520.cc
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ testsuite/gdb.base/pr15520.cc	16 Sep 2013 08:06:03 -0000
@@ -0,0 +1,33 @@
+# 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 <string>
+using namespace std;
+
+void
+fun (string &str1, string &str2)
+{
+  str1 += str2;
+}
+
+int
+main (void)
+{
+  string str1 = "abc";
+  string str2 = "def";
+  fun(str1,str2);
+
+  return 0;
+}
Index: testsuite/gdb.base/pr15520.exp
===================================================================
RCS file: testsuite/gdb.base/pr15520.exp
diff -N testsuite/gdb.base/pr15520.exp
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ testsuite/gdb.base/pr15520.exp	16 Sep 2013 08:06:03 -0000
@@ -0,0 +1,36 @@
+# 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/>.
+
+#
+# test running programs
+#
+standard_testfile .cc
+
+if {[prepare_for_testing $testfile.exp $testfile $srcfile {debug c++}]} {
+    return -1
+}
+
+if ![runto_main] {
+    untested non-stop-step
+    return -1
+}
+
+gdb_test "set target-async on" ".*" "Set async mode"
+gdb_test "set non-stop on" ".*" "Set non stop mode"
+
+gdb_breakpoint "fun"
+gdb_continue_to_breakpoint "fun"
+gdb_test "step" ".*}.*" "step 1"
+gdb_test "step" ".*main .*$srcfile.*\[\n\r\].*return 0;.*" "step 2"