[PATCH] [gdb/python] Make gdb.UnwindInfo.add_saved_register more robust (fixup)

[PATCH] [gdb/python] Make gdb.UnwindInfo.add_saved_register more robust (fixup)

[Tom de Vries]

In commit 2236c5e384d ("[gdb/python] Make gdb.UnwindInfo.add_saved_register
more robust") I added this code in unwind_infopy_add_saved_register:
...
  if (value->optimized_out () || !value->entirely_available ())
...
which may throw c++ exceptions.

This needs to be caught and transformed into a python exception.

Fix this by using GDB_PY_HANDLE_EXCEPTION.

Tested on x86_64-linux.

Fixes: 2236c5e384d ("[gdb/python] Make gdb.UnwindInfo.add_saved_register more robust")
---
 gdb/python/py-unwind.c | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/gdb/python/py-unwind.c b/gdb/python/py-unwind.c
index 18125e56a46..2f4f88ab10a 100644
--- a/gdb/python/py-unwind.c
+++ b/gdb/python/py-unwind.c
@@ -361,16 +361,24 @@ unwind_infopy_add_saved_register (PyObject *self, PyObject *args, PyObject *kw)
       return nullptr;
     }
 
-  if (value->optimized_out () || !value->entirely_available ())
+
+  try
+    {
+      if (value->optimized_out () || !value->entirely_available ())
+	{
+	  /* If we allow this value to be registered here, pyuw_sniffer is going
+	     to run into an exception when trying to access its contents.
+	     Throwing an exception here just puts a burden on the user to
+	     implement the same checks on the user side.  We could return False
+	     here and True otherwise, but again that might require changes in user
+	     code.  So, handle this with minimal impact for the user, while
+	     improving robustness: silently ignore the register/value pair.  */
+	  Py_RETURN_NONE;
+	}
+    }
+  catch (const gdb_exception &except)
     {
-      /* If we allow this value to be registered here, pyuw_sniffer is going
-	 to run into an exception when trying to access its contents.
-	 Throwing an exception here just puts a burden on the user to
-	 implement the same checks on the user side.  We could return False
-	 here and True otherwise, but again that might require changes in user
-	 code.  So, handle this with minimal impact for the user, while
-	 improving robustness: silently ignore the register/value pair.  */
-      Py_RETURN_NONE;
+      GDB_PY_HANDLE_EXCEPTION (except);
     }
 
   gdbpy_ref<> new_value = gdbpy_ref<>::new_reference (pyo_reg_value);

base-commit: 0fd705062ee0bb570ac7a1201d6f3cc2ed96f95d
-- 
2.35.3

Re: [PATCH] [gdb/python] Make gdb.UnwindInfo.add_saved_register more robust (fixup)

[Tom Tromey]

>>>>> "Tom" == Tom de Vries <tdevries@suse.de> writes:

Tom> In commit 2236c5e384d ("[gdb/python] Make gdb.UnwindInfo.add_saved_register
Tom> more robust") I added this code in unwind_infopy_add_saved_register:
Tom> ...
Tom>   if (value->optimized_out () || !value->entirely_available ())
Tom> ...
Tom> which may throw c++ exceptions.

Tom> This needs to be caught and transformed into a python exception.

Tom> Fix this by using GDB_PY_HANDLE_EXCEPTION.

Tom> Tested on x86_64-linux.

Thank you.
Approved-By: Tom Tromey <tom@tromey.com>

Tom