FreeChainXenon/binutils-gdb
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Change how Python architecture and language are handled

Browse source 
Currently, gdb's Python layer captures the current architecture and
language when "entering" Python code.  This has some undesirable
effects, and so this series changes how this is handled.

First, there is code like this:

  gdbpy_enter enter_py (python_gdbarch, python_language);

This is incorrect, because both of these are NULL when not otherwise
assigned.  This can cause crashes in some cases -- I've added one to
the test suite.  (Note that this crasher is just an example, other
ones along the same lines are possible.)

Second, when the language is captured in this way, it means that
Python code cannot affect the current language for its own purposes.
It's reasonable to want to write code like this:

    gdb.execute('set language mumble')
    ... stuff using the current language
    gdb.execute('set language previous-value')

However, this won't actually work, because the language is captured on
entry.  I've added a test to show this as well.

This patch changes gdb to try to avoid capturing the current values.
The Python concept of the current gdbarch is only set in those few
cases where a non-default value is computed or needed; and the
language is not captured at all -- instead, in the cases where it's
required, the current language is temporarily changed.
This commit is contained in:
Tom Tromey 2022-01-04 08:02:24 -07:00
parent 8a782bbf70
commit 1da5d0e664
20 changed files with 146 additions and 105 deletions
Download patch file Download diff file Expand all files Collapse all files

8
gdb/python/py-cmd.c
View file

@ -90,7 +90,7 @@ cmdpy_dont_repeat (PyObject *self, PyObject *args)
static void
cmdpy_destroyer (struct cmd_list_element *self, void *context)
{
gdbpy_enter enter_py (get_current_arch (), current_language);
gdbpy_enter enter_py;
/* Release our hold on the command object. */
gdbpy_ref<cmdpy_object> cmd ((cmdpy_object *) context);
@ -104,7 +104,7 @@ cmdpy_function (const char *args, int from_tty, cmd_list_element *command)
{
cmdpy_object *obj = (cmdpy_object *) command->context ();
gdbpy_enter enter_py (get_current_arch (), current_language);
gdbpy_enter enter_py;
if (! obj)
error (_("Invalid invocation of Python command object."));
@ -223,7 +223,7 @@ cmdpy_completer_handle_brkchars (struct cmd_list_element *command,
completion_tracker &tracker,
const char *text, const char *word)
{
gdbpy_enter enter_py (get_current_arch (), current_language);
gdbpy_enter enter_py;
/* Calling our helper to obtain a reference to the PyObject of the Python
function. */
@ -266,7 +266,7 @@ cmdpy_completer (struct cmd_list_element *command,
completion_tracker &tracker,
const char *text, const char *word)
{
gdbpy_enter enter_py (get_current_arch (), current_language);
gdbpy_enter enter_py;
/* Calling our helper to obtain a reference to the PyObject of the Python
function. */