[Ada] Allow assignment to wide string.

Given the following variable declaration...

   Www : Wide_String := "12345";

... this patch allows the following assignment to work:

   (gdb) set variable www := "qwert"

Without this patch, the debugger rejects the assignment because
the size of the array elements are different:

   (gdb) set www := "asdfg"
   Incompatible types in assignment

(on the lhs, we have an array of 2-bytes elements, and on the rhs,
we have a standard 1-byte string).

gdb/ChangeLog:

        * ada-lang.c (ada_same_array_size_p): New function.
        (ada_promote_array_of_integrals): New function.
        (coerce_for_assign): Add handling of arrays where the elements
        are integrals of a smaller size than the size of the target
        array element type.

gdb/testsuite/ChangeLog:

        * gdb.ada/set_wstr: New testcase.

1 files changed, 21 insertions, 0 deletions

diff --git a/gdb/testsuite/gdb.ada/set_wstr/pck.adb b/gdb/testsuite/gdb.ada/set_wstr/pck.adb
new file mode 100644
index 00000000000..1f7d45cf5e2
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/set_wstr/pck.adb
@@ -0,0 +1,21 @@
+--  Copyright 2012 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/>.
+
+package body Pck is
+   procedure Do_Nothing (A : System.Address) is
+   begin
+      null;
+   end Do_Nothing;
+end Pck;