[binutils-gdb] Do not expose stub types to Python

[gdb-buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT 5d63b30afa2d1e24a3d1e6fe97507473e0545a02 ***

commit 5d63b30afa2d1e24a3d1e6fe97507473e0545a02
Author:     Tom Tromey <tromey@adacore.com>
AuthorDate: Mon Aug 19 13:41:34 2019 -0600
Commit:     Tom Tromey <tromey@adacore.com>
CommitDate: Thu Sep 26 08:26:12 2019 -0600

    Do not expose stub types to Python
    
    dwarf2read.c will create stub types for Ada "Taft Amendment" types.
    These stub types can currently be exposed to Python code, where they
    show up as TYPE_CODE_VOID types (but that, mysteriously, can sometimes
    be used in other ways).
    
    While it's possible to work with such types by using strip_typedefs,
    this seemed unpleasant to me.  This patch takes another approach
    instead, which is to try not to expose stub types to Python users.
    
    gdb/ChangeLog
    2019-09-26  Tom Tromey  <tromey@adacore.com>
    
            * python/py-type.c (type_to_type_object): Call check_typedef
            for stub types.
    
    gdb/testsuite/ChangeLog
    2019-09-26  Tom Tromey  <tromey@adacore.com>
    
            * gdb.ada/py_taft.exp: New file.
            * gdb.ada/py_taft/main.adb: New file.
            * gdb.ada/py_taft/pkg.adb: New file.
            * gdb.ada/py_taft/pkg.ads: New file.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index bc6c20375b..433b239b58 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2019-09-26  Tom Tromey  <tromey@adacore.com>
+
+	* python/py-type.c (type_to_type_object): Call check_typedef
+	for stub types.
+
 2019-09-26  Tom Tromey  <tom@tromey.com>
 
 	* utils.h (initialize_utils): Don't declare.
diff --git a/gdb/python/py-type.c b/gdb/python/py-type.c
index e8af6f60e1..134f76dafb 100644
--- a/gdb/python/py-type.c
+++ b/gdb/python/py-type.c
@@ -1334,6 +1334,17 @@ type_to_type_object (struct type *type)
 {
   type_object *type_obj;
 
+  try
+    {
+      /* Try not to let stub types leak out to Python.  */
+      if (TYPE_STUB (type))
+	type = check_typedef (type);
+    }
+  catch (...)
+    {
+      /* Just ignore failures in check_typedef.  */
+    }
+
   type_obj = PyObject_New (type_object, &type_object_type);
   if (type_obj)
     set_type (type_obj, type);
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 706c5da420..56ee785b1f 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,10 @@
+2019-09-26  Tom Tromey  <tromey@adacore.com>
+
+	* gdb.ada/py_taft.exp: New file.
+	* gdb.ada/py_taft/main.adb: New file.
+	* gdb.ada/py_taft/pkg.adb: New file.
+	* gdb.ada/py_taft/pkg.ads: New file.
+
 2019-09-24  Tom de Vries  <tdevries@suse.de>
 
 	PR gdb/24598
diff --git a/gdb/testsuite/gdb.ada/py_taft.exp b/gdb/testsuite/gdb.ada/py_taft.exp
new file mode 100644
index 0000000000..71ac332738
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/py_taft.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"
+load_lib gdb-python.exp
+
+standard_ada_testfile main
+
+if {[gdb_compile_ada "${srcfile}" "${binfile}" executable debug] != ""} {
+    return -1
+}
+
+clean_restart ${testfile}
+
+# Skip this testcase if Python scripting is not enabled.
+if { [skip_python_tests] } { continue }
+
+set bp_location [gdb_get_line_number "STOP" ${testdir}/main.adb]
+runto "main.adb:$bp_location"
+
+gdb_test_no_output "python v = gdb.parse_and_eval('v')"
+
+gdb_test "python print(v.dereference().type.code is gdb.TYPE_CODE_VOID)" \
+    "False"
+gdb_test "python print(v.type.strip_typedefs().target().code is gdb.TYPE_CODE_VOID)" \
+    "False"
diff --git a/gdb/testsuite/gdb.ada/py_taft/main.adb b/gdb/testsuite/gdb.ada/py_taft/main.adb
new file mode 100644
index 0000000000..b0ba8bdb90
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/py_taft/main.adb
@@ -0,0 +1,22 @@
+--  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/>.
+
+with Pkg;
+
+procedure Main is
+   V : Pkg.Value := Pkg.Create (42);
+begin
+   null;				--  STOP
+end Main;
diff --git a/gdb/testsuite/gdb.ada/py_taft/pkg.adb b/gdb/testsuite/gdb.ada/py_taft/pkg.adb
new file mode 100644
index 0000000000..94ce4b1e85
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/py_taft/pkg.adb
@@ -0,0 +1,27 @@
+--  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/>.
+
+package body Pkg is
+
+   type Value_Record is record
+      I : Integer;
+   end record;
+
+   function Create (I : Integer) return Value is
+   begin
+      return new Value_Record'(I => I);
+   end Create;
+
+end Pkg;
diff --git a/gdb/testsuite/gdb.ada/py_taft/pkg.ads b/gdb/testsuite/gdb.ada/py_taft/pkg.ads
new file mode 100644
index 0000000000..daa4edbf1b
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/py_taft/pkg.ads
@@ -0,0 +1,22 @@
+--  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/>.
+
+package Pkg is
+   type Value is private;
+   function Create (I : Integer) return Value;
+private
+   type Value_Record;
+   type Value is access all Value_Record;
+end Pkg;