gdb/gdb-archer.patch

http://sourceware.org/gdb/wiki/ProjectArcher
http://sourceware.org/gdb/wiki/ArcherBranchManagement

GIT snapshot:
commit b88230edf4e2da948d633c283ba0893bf22bd7ae

tromey/python


Index: gdb-7.8/README.archer
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ gdb-7.8/README.archer	2014-07-29 19:29:04.861982779 +0200
@@ -0,0 +1,2 @@
+This branch originally held the Python code for gdb.  It still exists
+because a small amount of code here has not yet been merged upstream.
Index: gdb-7.8/gdb/Makefile.in
===================================================================
--- gdb-7.8.orig/gdb/Makefile.in	2014-07-29 19:29:02.665979655 +0200
+++ gdb-7.8/gdb/Makefile.in	2014-07-29 19:29:04.862982781 +0200
@@ -1476,6 +1476,12 @@ stamp-h: $(srcdir)/config.in config.stat
 	  CONFIG_LINKS= \
 	  $(SHELL) config.status
 
+.gdbinit: $(srcdir)/gdbinit.in config.status
+	CONFIG_FILES=".gdbinit:gdbinit.in" \
+	  CONFIG_COMMANDS= \
+	  CONFIG_HEADERS= \
+	  $(SHELL) config.status
+
 config.status: $(srcdir)/configure configure.tgt configure.host ../bfd/development.sh
 	$(SHELL) config.status --recheck
 
Index: gdb-7.8/gdb/data-directory/Makefile.in
===================================================================
--- gdb-7.8.orig/gdb/data-directory/Makefile.in	2014-07-29 19:29:02.665979655 +0200
+++ gdb-7.8/gdb/data-directory/Makefile.in	2014-07-29 19:29:33.053022486 +0200
@@ -65,6 +65,8 @@ PYTHON_FILE_LIST = \
 	gdb/prompt.py \
 	gdb/xmethod.py \
 	gdb/command/__init__.py \
+	gdb/command/ignore_errors.py \
+	gdb/command/pahole.py \
 	gdb/command/xmethods.py \
 	gdb/command/frame_filters.py \
 	gdb/command/type_printers.py \
@@ -74,7 +76,10 @@ PYTHON_FILE_LIST = \
 	gdb/function/__init__.py \
 	gdb/function/strfns.py \
 	gdb/printer/__init__.py \
-	gdb/printer/bound_registers.py
+	gdb/printer/bound_registers.py \
+	gdb/function/caller_is.py \
+	gdb/function/in_scope.py \
+	gdb/types.py
 
 @HAVE_PYTHON_TRUE@PYTHON_FILES = $(PYTHON_FILE_LIST)
 @HAVE_PYTHON_FALSE@PYTHON_FILES =
Index: gdb-7.8/gdb/doc/gdb.texinfo
===================================================================
--- gdb-7.8.orig/gdb/doc/gdb.texinfo	2014-07-29 19:29:02.675979669 +0200
+++ gdb-7.8/gdb/doc/gdb.texinfo	2014-07-29 19:29:04.871982794 +0200
@@ -1225,6 +1225,16 @@ for remote debugging.
 Run using @var{device} for your program's standard input and output.
 @c FIXME: kingdon thinks there is more to -tty.  Investigate.
 
+@item -P
+@cindex @code{-P}
+@itemx --python
+@cindex @code{--python}
+Change interpretation of command line so that the argument immediately
+following this switch is taken to be the name of a Python script file.
+This option stops option processing; subsequent options are passed to
+Python as @code{sys.argv}.  This option is only available if Python
+scripting support was enabled when @value{GDBN} was configured.
+
 @c resolve the situation of these eventually
 @item -tui
 @cindex @code{--tui}
Index: gdb-7.8/gdb/doc/python.texi
===================================================================
--- gdb-7.8.orig/gdb/doc/python.texi	2014-07-29 19:29:02.677979672 +0200
+++ gdb-7.8/gdb/doc/python.texi	2014-07-29 19:29:04.872982795 +0200
@@ -88,8 +88,6 @@ containing @code{end}.  For example:
 
 @smallexample
 (@value{GDBP}) python
-Type python script
-End with a line saying just "end".
 >print 23
 >end
 23
Index: gdb-7.8/gdb/gdb-gdb.gdb.in
===================================================================
--- gdb-7.8.orig/gdb/gdb-gdb.gdb.in	2014-07-29 19:29:02.677979672 +0200
+++ gdb-7.8/gdb/gdb-gdb.gdb.in	2014-07-29 19:29:04.872982795 +0200
@@ -1,5 +1,15 @@
 echo Setting up the environment for debugging gdb.\n
 
+# Set up the Python library and "require" command.
+python
+from os.path import abspath
+gdb.datadir = abspath ('@srcdir@/python/lib')
+gdb.pythonlibdir = gdb.datadir
+gdb.__path__ = [gdb.datadir + '/gdb']
+sys.path.insert(0, gdb.datadir)
+end
+source @srcdir@/python/lib/gdb/__init__.py
+
 if !$gdb_init_done
   set variable $gdb_init_done = 1
 
Index: gdb-7.8/gdb/main.c
===================================================================
--- gdb-7.8.orig/gdb/main.c	2014-07-29 19:29:02.678979673 +0200
+++ gdb-7.8/gdb/main.c	2014-07-29 19:29:04.872982795 +0200
@@ -37,6 +37,7 @@
 
 #include "interps.h"
 #include "main.h"
+#include "python/python.h"
 #include "source.h"
 #include "cli/cli-cmds.h"
 #include "objfiles.h"
@@ -417,6 +418,8 @@ captured_main (void *data)
   char *cdarg = NULL;
   char *ttyarg = NULL;
 
+  int python_script = 0;
+
   /* These are static so that we can take their address in an
      initializer.  */
   static int print_help;
@@ -624,10 +627,14 @@ captured_main (void *data)
       {"args", no_argument, &set_args, 1},
       {"l", required_argument, 0, 'l'},
       {"return-child-result", no_argument, &return_child_result, 1},
+#if HAVE_PYTHON
+      {"python", no_argument, 0, 'P'},
+      {"P", no_argument, 0, 'P'},
+#endif
       {0, no_argument, 0, 0}
     };
 
-    while (1)
+    while (!python_script)
       {
 	int option_index;
 
@@ -645,6 +652,9 @@ captured_main (void *data)
 	  case 0:
 	    /* Long option that just sets a flag.  */
 	    break;
+	  case 'P':
+	    python_script = 1;
+	    break;
 	  case OPT_SE:
 	    symarg = optarg;
 	    execarg = optarg;
@@ -849,7 +859,31 @@ captured_main (void *data)
 
   /* Now that gdb_init has created the initial inferior, we're in
      position to set args for that inferior.  */
-  if (set_args)
+  if (python_script)
+    {
+      /* The first argument is a python script to evaluate, and
+	 subsequent arguments are passed to the script for
+	 processing there.  */
+      if (optind >= argc)
+	{
+	  fprintf_unfiltered (gdb_stderr,
+			      _("%s: Python script file name required\n"),
+			      argv[0]);
+	  exit (1);
+	}
+
+      /* FIXME: should handle inferior I/O intelligently here.
+	 E.g., should be possible to run gdb in pipeline and have
+	 Python (and gdb) output go to stderr or file; and if a
+	 prompt is needed, open the tty.  */
+      quiet = 1;
+      /* FIXME: should read .gdbinit if, and only if, a prompt is
+	 requested by the script.  Though... maybe this is not
+	 ideal?  */
+      /* FIXME: likewise, reading in history.  */
+      inhibit_gdbinit = 1;
+    }
+  else if (set_args)
     {
       /* The remaining options are the command-line options for the
 	 inferior.  The first one is the sym/exec file, and the rest
@@ -1135,7 +1169,8 @@ captured_main (void *data)
 
   /* Read in the old history after all the command files have been
      read.  */
-  init_history ();
+  if (!python_script)
+    init_history ();
 
   if (batch_flag)
     {
@@ -1146,13 +1181,25 @@ captured_main (void *data)
   /* Show time and/or space usage.  */
   do_cleanups (pre_stat_chain);
 
-  /* NOTE: cagney/1999-11-07: There is probably no reason for not
-     moving this loop and the code found in captured_command_loop()
-     into the command_loop() proper.  The main thing holding back that
-     change - SET_TOP_LEVEL() - has been eliminated.  */
-  while (1)
+#if HAVE_PYTHON
+  if (python_script)
     {
-      catch_errors (captured_command_loop, 0, "", RETURN_MASK_ALL);
+      extern int pagination_enabled;
+      pagination_enabled = 0;
+      run_python_script (argc - optind, &argv[optind]);
+      return 1;
+    }
+  else
+#endif
+    {
+      /* NOTE: cagney/1999-11-07: There is probably no reason for not
+	 moving this loop and the code found in captured_command_loop()
+	 into the command_loop() proper.  The main thing holding back that
+	 change - SET_TOP_LEVEL() - has been eliminated. */
+      while (1)
+	{
+	  catch_errors (captured_command_loop, 0, "", RETURN_MASK_ALL);
+	}
     }
   /* No exit -- exit is through quit_command.  */
 }
@@ -1186,6 +1233,12 @@ print_gdb_help (struct ui_file *stream)
   fputs_unfiltered (_("\
 This is the GNU debugger.  Usage:\n\n\
     gdb [options] [executable-file [core-file or process-id]]\n\
+    gdb [options] --args executable-file [inferior-arguments ...]\n"), stream);
+#if HAVE_PYTHON
+  fputs_unfiltered (_("\
+    gdb [options] [--python|-P] script-file [script-arguments ...]\n"), stream);
+#endif
+  fputs_unfiltered (_("\n\
     gdb [options] --args executable-file [inferior-arguments ...]\n\n\
 "), stream);
   fputs_unfiltered (_("\
@@ -1231,6 +1284,13 @@ Output and user interface control:\n\n\
   fputs_unfiltered (_("\
   --dbx              DBX compatibility mode.\n\
   --xdb              XDB compatibility mode.\n\
+"), stream);
+#if HAVE_PYTHON
+  fputs_unfiltered (_("\
+  --python, -P       Following argument is Python script file; remaining\n\
+                     arguments are passed to script.\n"), stream);
+#endif
+  fputs_unfiltered (_("\
   -q, --quiet, --silent\n\
                      Do not print version number on startup.\n\n\
 "), stream);
Index: gdb-7.8/gdb/python/lib/gdb/command/ignore_errors.py
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ gdb-7.8/gdb/python/lib/gdb/command/ignore_errors.py	2014-07-29 19:29:04.872982795 +0200
@@ -0,0 +1,37 @@
+# Ignore errors in user commands.
+
+# Copyright (C) 2008 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/>.
+
+import gdb
+
+class IgnoreErrorsCommand (gdb.Command):
+    """Execute a single command, ignoring all errors.
+Only one-line commands are supported.
+This is primarily useful in scripts."""
+
+    def __init__ (self):
+        super (IgnoreErrorsCommand, self).__init__ ("ignore-errors",
+                                                    gdb.COMMAND_OBSCURE,
+                                                    # FIXME...
+                                                    gdb.COMPLETE_COMMAND)
+
+    def invoke (self, arg, from_tty):
+        try:
+            gdb.execute (arg, from_tty)
+        except:
+            pass
+
+IgnoreErrorsCommand ()
Index: gdb-7.8/gdb/python/lib/gdb/command/pahole.py
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ gdb-7.8/gdb/python/lib/gdb/command/pahole.py	2014-07-29 19:29:04.873982797 +0200
@@ -0,0 +1,81 @@
+# pahole command for gdb
+
+# Copyright (C) 2008, 2009, 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/>.
+
+import gdb
+
+class Pahole (gdb.Command):
+    """Show the holes in a structure.
+This command takes a single argument, a type name.
+It prints the type and displays comments showing where holes are."""
+
+    def __init__ (self):
+        super (Pahole, self).__init__ ("pahole", gdb.COMMAND_NONE,
+                                       gdb.COMPLETE_SYMBOL)
+
+    def maybe_print_hole(self, bitpos, field_bitpos):
+        if bitpos != field_bitpos:
+            hole = field_bitpos - bitpos
+            print '  /* XXX %d bit hole, try to pack */' % hole
+
+    def pahole (self, type, level, name):
+        if name is None:
+            name = ''
+        tag = type.tag
+        if tag is None:
+            tag = ''
+        print '%sstruct %s {' % (' ' * (2 * level), tag)
+        bitpos = 0
+        for field in type.fields ():
+            # Skip static fields.
+            if not hasattr (field, ('bitpos')):
+                continue
+
+            ftype = field.type.strip_typedefs()
+
+            self.maybe_print_hole(bitpos, field.bitpos)
+            bitpos = field.bitpos
+            if field.bitsize > 0:
+                fieldsize = field.bitsize
+            else:
+                # TARGET_CHAR_BIT here...
+                fieldsize = 8 * ftype.sizeof
+
+            # TARGET_CHAR_BIT
+            print ' /* %3d %3d */' % (int (bitpos / 8), int (fieldsize / 8)),
+            bitpos = bitpos + fieldsize
+
+            if ftype.code == gdb.TYPE_CODE_STRUCT:
+                self.pahole (ftype, level + 1, field.name)
+            else:
+                print ' ' * (2 + 2 * level),
+                print '%s %s' % (str (ftype), field.name)
+
+        if level == 0:
+            self.maybe_print_hole(bitpos, 8 * type.sizeof)
+
+        print ' ' * (14 + 2 * level),
+        print '} %s' % name
+
+    def invoke (self, arg, from_tty):
+        type = gdb.lookup_type (arg)
+        type = type.strip_typedefs ()
+        if type.code != gdb.TYPE_CODE_STRUCT:
+            raise TypeError, '%s is not a struct type' % arg
+        print ' ' * 14,
+        self.pahole (type, 0, '')
+
+Pahole()
Index: gdb-7.8/gdb/python/lib/gdb/function/caller_is.py
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ gdb-7.8/gdb/python/lib/gdb/function/caller_is.py	2014-07-29 19:29:04.873982797 +0200
@@ -0,0 +1,58 @@
+# Caller-is functions.
+
+# Copyright (C) 2008 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/>.
+
+import gdb
+import re
+
+class CallerIs (gdb.Function):
+    """Return True if the calling function's name is equal to a string.
+This function takes one or two arguments.
+The first argument is the name of a function; if the calling function's
+name is equal to this argument, this function returns True.
+The optional second argument tells this function how many stack frames
+to traverse to find the calling function.  The default is 1."""
+
+    def __init__ (self):
+        super (CallerIs, self).__init__ ("caller_is")
+
+    def invoke (self, name, nframes = 1):
+        frame = gdb.selected_frame ()
+        while nframes > 0:
+            frame = frame.older ()
+            nframes = nframes - 1
+        return frame.name () == name.string ()
+
+class CallerMatches (gdb.Function):
+    """Return True if the calling function's name matches a string.
+This function takes one or two arguments.
+The first argument is a regular expression; if the calling function's
+name is matched by this argument, this function returns True.
+The optional second argument tells this function how many stack frames
+to traverse to find the calling function.  The default is 1."""
+
+    def __init__ (self):
+        super (CallerMatches, self).__init__ ("caller_matches")
+
+    def invoke (self, name, nframes = 1):
+        frame = gdb.selected_frame ()
+        while nframes > 0:
+            frame = frame.older ()
+            nframes = nframes - 1
+        return re.match (name.string (), frame.name ()) is not None
+
+CallerIs()
+CallerMatches()
Index: gdb-7.8/gdb/python/lib/gdb/function/in_scope.py
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ gdb-7.8/gdb/python/lib/gdb/function/in_scope.py	2014-07-29 19:29:04.873982797 +0200
@@ -0,0 +1,47 @@
+# In-scope function.
+
+# Copyright (C) 2008 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/>.
+
+import gdb
+
+class InScope (gdb.Function):
+    """Return True if all the given variables or macros are in scope.
+Takes one argument for each variable name to be checked."""
+
+    def __init__ (self):
+	super (InScope, self).__init__ ("in_scope")
+
+    def invoke (self, *vars):
+        if len (vars) == 0:
+	    raise TypeError, "in_scope takes at least one argument"
+
+        # gdb.Value isn't hashable so it can't be put in a map.
+	# Convert to string first.
+	wanted = set (map (lambda x: x.string (), vars))
+	found = set ()
+	block = gdb.selected_frame ().block ()
+	while block:
+	    for sym in block:
+		if (sym.is_argument or sym.is_constant
+		      or sym.is_function or sym.is_variable):
+		    if sym.name in wanted:
+			found.add (sym.name)
+
+	    block = block.superblock
+
+	return wanted == found
+
+InScope ()
Index: gdb-7.8/gdb/python/python.c
===================================================================
--- gdb-7.8.orig/gdb/python/python.c	2014-07-29 19:29:02.679979674 +0200
+++ gdb-7.8/gdb/python/python.c	2014-07-29 19:29:04.873982797 +0200
@@ -95,6 +95,8 @@ const struct extension_language_defn ext
 #include "linespec.h"
 #include "source.h"
 #include "version.h"
+#include "inferior.h"
+#include "gdbthread.h"
 #include "target.h"
 #include "gdbthread.h"
 #include "interps.h"
@@ -1222,6 +1224,56 @@ gdbpy_print_stack (void)
 
 /* Return the current Progspace.
    There always is one.  */
+/* True if 'gdb -P' was used, false otherwise.  */
+static int running_python_script;
+
+/* True if we are currently in a call to 'gdb.cli', false otherwise.  */
+static int in_cli;
+
+/* Enter the command loop.  */
+
+static PyObject *
+gdbpy_cli (PyObject *unused1, PyObject *unused2)
+{
+  if (! running_python_script || in_cli)
+    return PyErr_Format (PyExc_RuntimeError, "cannot invoke CLI recursively");
+  
+  if (ui_out_is_mi_like_p (current_uiout))
+    return PyErr_Format (PyExc_RuntimeError, _("Cannot invoke CLI from MI."));
+
+  in_cli = 1;
+  current_interp_command_loop ();
+  in_cli = 0;
+
+  Py_RETURN_NONE;
+}
+
+/* Set up the Python argument vector and evaluate a script.  This is
+   used to implement 'gdb -P'.  */
+
+void
+run_python_script (int argc, char **argv)
+{
+  FILE *input;
+
+  /* We never free this, since we plan to exit at the end.  */
+  ensure_python_env (get_current_arch (), current_language);
+
+  running_python_script = 1;
+  PySys_SetArgv (argc - 1, argv + 1);
+  input = fopen (argv[0], "r");
+  if (! input)
+    {
+      fprintf (stderr, "could not open %s: %s\n", argv[0], strerror (errno));
+      exit (1);
+    }
+  PyRun_SimpleFile (input, argv[0]);
+  fclose (input);
+  exit (0);
+}
+
+
+
 
 static PyObject *
 gdbpy_get_current_progspace (PyObject *unused1, PyObject *unused2)
@@ -1910,6 +1962,8 @@ static PyMethodDef GdbMethods[] =
 Evaluate command, a string, as a gdb CLI command.  Optionally returns\n\
 a Python String containing the output of the command if to_string is\n\
 set to True." },
+  { "cli", gdbpy_cli, METH_NOARGS,
+    "Enter the gdb CLI" },
   { "parameter", gdbpy_parameter, METH_VARARGS,
     "Return a gdb parameter's value" },
 
Index: gdb-7.8/gdb/python/python.h
===================================================================
--- gdb-7.8.orig/gdb/python/python.h	2014-07-29 19:29:02.679979674 +0200
+++ gdb-7.8/gdb/python/python.h	2014-07-29 19:29:04.873982797 +0200
@@ -25,4 +25,6 @@
 /* This is all that python exports to gdb.  */
 extern const struct extension_language_defn extension_language_python;
 
+extern void run_python_script (int argc, char **argv);
+
 #endif /* GDB_PYTHON_H */
Index: gdb-7.8/gdb/testsuite/gdb.gdb/selftest.exp
===================================================================
--- gdb-7.8.orig/gdb/testsuite/gdb.gdb/selftest.exp	2014-07-29 19:29:02.679979674 +0200
+++ gdb-7.8/gdb/testsuite/gdb.gdb/selftest.exp	2014-07-29 19:29:04.874982798 +0200
@@ -92,6 +92,10 @@ proc do_steps_and_nexts {} {
 		set description "step over cmdarg_vec initialization"
 		set command "step"
 	    }
+	    -re ".*python_script = 0.*$gdb_prompt $" {
+		set description "step over python_script initialization"
+		set command "step"
+	    }
 	    -re ".*pre_stat_chain = make_command_stats_cleanup.*$gdb_prompt $" {
 		set description "next over make_command_stats_cleanup and everything it calls"
 		set command "next"
Index: gdb-7.8/gdb/testsuite/gdb.python/py-frame.exp
===================================================================
--- gdb-7.8.orig/gdb/testsuite/gdb.python/py-frame.exp	2014-07-29 19:29:02.680979676 +0200
+++ gdb-7.8/gdb/testsuite/gdb.python/py-frame.exp	2014-07-29 19:29:04.874982798 +0200
@@ -94,3 +94,5 @@ gdb_test "python print ('result = %s' %
 gdb_test "python print ('result = %s' % f0.read_var ('a'))" " = 1" "test Frame.read_var - success"
 
 gdb_test "python print ('result = %s' % (gdb.selected_frame () == f1))" " = True" "test gdb.selected_frame"
+
+gdb_test "python print ('result = %s' % (f0.block ()))" "<gdb.Block object at 0x\[\[:xdigit:\]\]+>" "test Frame.block"
Index: gdb-7.8/gdb/testsuite/gdb.python/py-value.exp
===================================================================
--- gdb-7.8.orig/gdb/testsuite/gdb.python/py-value.exp	2014-07-29 19:29:02.680979676 +0200
+++ gdb-7.8/gdb/testsuite/gdb.python/py-value.exp	2014-07-29 19:29:04.874982798 +0200
@@ -385,6 +385,15 @@ proc test_value_after_death {} {
     "print value's type"
 }
 
+# Regression test for a cast failure.  The bug was that if we cast a
+# value to its own type, gdb could crash.  This happened because we
+# could end up double-freeing a struct value.
+proc test_cast_regression {} {
+  gdb_test "python v = gdb.Value(5)" "" "create value for cast test"
+  gdb_test "python v = v.cast(v.type)" "" "cast value for cast test"
+  gdb_test "python print v" "5" "print value for cast test"
+}
+
 # Regression test for invalid subscript operations.  The bug was that
 # the type of the value was not being checked before allowing a
 # subscript operation to proceed.
@@ -514,6 +523,7 @@ test_value_in_inferior
 test_inferior_function_call
 test_lazy_strings
 test_value_after_death
+test_cast_regression
 
 # Test either C or C++ values.