Fix VLA printing for Ada

While looking at a different Ada problem, I found that printing a
record containing a VLA did not work properly.

I tracked the problem down to dwarf2_evaluate_property trying, and
failing, to compare two types that differed only in qualifiers.

This patch changes dwarf2_evaluate_property to ignore qualifiers when
comparing types.

Tested on x86-64 Fedora 29.

gdb/ChangeLog
2019-05-08  Tom Tromey  <tromey@adacore.com>

	* dwarf2loc.c (dwarf2_evaluate_property) <PROP_ADDR_OFFSET>:
	Compare main types.

gdb/testsuite/ChangeLog
2019-05-08  Tom Tromey  <tromey@adacore.com>

	* gdb.ada/vla.exp: New file.
	* gdb.ada/vla/vla.adb: New file.

gdb/ChangeLog

@@ -1,3 +1,8 @@
+2019-05-08  Tom Tromey  <tromey@adacore.com>
+
+	* dwarf2loc.c (dwarf2_evaluate_property) <PROP_ADDR_OFFSET>:
+	Compare main types.
+
 2019-05-06  Tom Tromey  <tom@tromey.com>
 
 	* common/scoped_mmap.c: Include common-defs.h.

gdb/dwarf2loc.c

@@ -2493,8 +2493,12 @@ dwarf2_evaluate_property (const struct dynamic_prop *prop,
 	struct value *val;
 
 	for (pinfo = addr_stack; pinfo != NULL; pinfo = pinfo->next)
-	  if (pinfo->type == baton->referenced_type)
-	    break;
+	  {
+	    /* This approach lets us avoid checking the qualifiers.  */
+	    if (TYPE_MAIN_TYPE (pinfo->type)
+		== TYPE_MAIN_TYPE (baton->referenced_type))
+	      break;
+	  }
 	if (pinfo == NULL)
 	  error (_("cannot find reference address for offset property"));
 	if (pinfo->valaddr != NULL)

gdb/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2019-05-08  Tom Tromey  <tromey@adacore.com>
+
+	* gdb.ada/vla.exp: New file.
+	* gdb.ada/vla/vla.adb: New file.
+
 2019-05-07  Tom de Vries  <tdevries@suse.de>
 
 	* gdb.base/index-cache.exp (ls_host): Fix return statement.

gdb/testsuite/gdb.ada/vla.exp

@@ -0,0 +1,38 @@
+# Copyright 2019 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"
+
+if { [skip_ada_tests] } { return -1 }
+
+standard_ada_testfile vla
+
+if {[gdb_compile_ada "${srcfile}" "${binfile}" executable {debug}] != ""} {
+    return -1
+}
+
+clean_restart ${testfile}
+
+set bp_location [gdb_get_line_number "Set breakpoint here" ${testdir}/vla.adb]
+runto "vla.adb:$bp_location"
+
+gdb_test "print r00" \
+         "= \\(l1 => 0, l2 => 0, i1 => 1, i2 => 2, i3 => 3, a1 => \\(\\), a2 => \\(\\)\\)"
+gdb_test "print r01" \
+         "= \\(l1 => 0, l2 => 1, i1 => 1, i2 => 2, i3 => 3, a1 => \\(\\), a2 => \\(20\\)\\)"
+gdb_test "print r10" \
+         "= \\(l1 => 1, l2 => 0, i1 => 1, i2 => 2, i3 => 3, a1 => \\(10\\), a2 => \\(\\)\\)"
+gdb_test "print r22" \
+         "= \\(l1 => 2, l2 => 2, i1 => 1, i2 => 2, i3 => 3, a1 => \\(10, 10\\), a2 => \\(20, 20\\)\\)"

gdb/testsuite/gdb.ada/vla/vla.adb

@@ -0,0 +1,57 @@
+--  Copyright 2019 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/>.
+
+procedure Vla is
+   type Array_Type is array (Natural range <>) of Integer;
+   type Record_Type (L1, L2 : Natural) is record
+      I1 : Integer;
+      A1 : Array_Type (1 .. L1);
+      I2 : Integer;
+      A2 : Array_Type (1 .. L2);
+      I3 : Integer;
+   end record;
+
+   procedure Process (R : Record_Type) is
+   begin
+      null;
+   end Process;
+
+   R00 : Record_Type :=
+     (L1 => 0, L2 => 0,
+      I1 => 1, A1 => (others => 10),
+      I2 => 2, A2 => (others => 20),
+      I3 => 3);
+   R01 : Record_Type :=
+     (L1 => 0, L2 => 1,
+      I1 => 1, A1 => (others => 10),
+      I2 => 2, A2 => (others => 20),
+      I3 => 3);
+   R10 : Record_Type :=
+     (L1 => 1, L2 => 0,
+      I1 => 1, A1 => (others => 10),
+      I2 => 2, A2 => (others => 20),
+      I3 => 3);
+   R22 : Record_Type :=
+     (L1 => 2, L2 => 2,
+      I1 => 1, A1 => (others => 10),
+      I2 => 2, A2 => (others => 20),
+      I3 => 3);
+
+begin
+   Process (R00); -- Set breakpoint here
+   Process (R01);
+   Process (R10);
+   Process (R22);
+end Vla;