Ada: unable to compare strings (Attempt to compare array with non-array)

Consider the following Ada Code:

   type Str is new String (1 .. 4);
   My_str : Str := "ABCD";

This simply declares a 4-character string type. Trying to perform
equality tests using it currently yield an error:

    (gdb) p my_str = my_str
    Attempt to compare array with non-array
    (gdb) p my_str = "ABCD"
    Attempt to compare array with non-array

The error occurs because my_str is defined as an object whose
type is a typdef to a TYPE_CODE_ARRAY, which ada_value_equal
is not expecting at all (yet). This patch fixes this oversight.

gdb/ChangeLog:

        * ada-lang.c (ada_value_equal): Add handling of typedef types
        when comparing array objects.

gdb/testsuite/ChangeLog:

        * gdb.ada/str_binop_equal: New testcase.

Tested on x86_64-linux.

1 files changed, 39 insertions, 0 deletions

diff --git a/gdb/testsuite/gdb.ada/str_binop_equal.exp b/gdb/testsuite/gdb.ada/str_binop_equal.exp
new file mode 100644
index 0000000..2481bac
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/str_binop_equal.exp
@@ -0,0 +1,39 @@
+# Copyright 2017 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/>.
+
+load_lib "ada.exp"
+
+standard_ada_testfile foo_p211_061
+
+if {[gdb_compile_ada "${srcfile}" "${binfile}" executable [list debug]] != "" } {
+  return -1
+}
+
+clean_restart ${testfile}
+
+set bp_location [gdb_get_line_number "STOP" ${testdir}/foo_p211_061.adb]
+runto "foo_p211_061.adb:$bp_location"
+
+gdb_test "print my_str = my_str" \
+         " = true"
+
+gdb_test "print my_str = \"ABCD\"" \
+         " = true"
+
+gdb_test "print my_str = \"EFGH\"" \
+         " = false"
+
+gdb_test "print my_str = \"AB\"" \
+         " = false"