Installing a breakpoint on top of a dprintf makes GDB lose control.

While the full fix for PR 15180 isn't in, it's best if we at least
make sure that GDB doesn't lose control when a breakpoint is set at
the same address as a dprintf.

gdb/
2014-06-02  Pedro Alves  <palves@redhat.com>

	* breakpoint.c (build_target_command_list): Don't build a command
	list if we have any duplicate location that isn't a dprintf.

gdb/testsuite/
2014-06-02  Pedro Alves  <palves@redhat.com>

	* gdb.base/dprintf-bp-same-addr.c: New file.
	* gdb.base/dprintf-bp-same-addr.exp: New file.

1 files changed, 28 insertions, 0 deletions

diff --git a/gdb/testsuite/gdb.base/dprintf-bp-same-addr.c b/gdb/testsuite/gdb.base/dprintf-bp-same-addr.c
new file mode 100644
index 0000000..b28e102
--- /dev/null
+++ b/gdb/testsuite/gdb.base/dprintf-bp-same-addr.c
@@ -0,0 +1,28 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright (C) 2014 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/>.  */
+
+int
+main (void)
+{
+  int x = 1, y = 1, z = 1;
+
+  ++x; /* before dprintf */
+  ++y; /* set dprintf here */
+  ++z; /* after dprintf */
+
+  return 0;
+}