[PATCH 2/3] Fix latent bug in Python breakpoint creation

[Tom Tromey <tromey@adacore.com>]

While working on the previous patch, I noticed that Python breakpoint
creation does:

-	  = (qualified != NULL && PyObject_IsTrue (qualified)

PyObject_IsTrue can fail, so this is missing an error check.  This
patch adds the missing check.

Note that this could probably be improved by using the "p" format in
the call to gdb_PyArg_ParseTupleAndKeywords, but that was added in
Python 3.3, and I think gdb still supports 3.2.
---
 gdb/python/py-breakpoint.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/gdb/python/py-breakpoint.c b/gdb/python/py-breakpoint.c
index 917fd367d06..39d9bd5dff6 100644
--- a/gdb/python/py-breakpoint.c
+++ b/gdb/python/py-breakpoint.c
@@ -818,7 +818,7 @@ bppy_init_validate_args (const char *spec, char *source,
 static void
 bppy_create_breakpoint (enum bptype type, int access_type, int temporary_bp,
 			int internal_bp, const char *spec,
-			PyObject *qualified, const char *source,
+			int qualified, const char *source,
 			const char *function, const char *label,
 			const char *line)
 {
@@ -829,7 +829,7 @@ bppy_create_breakpoint (enum bptype type, int access_type, int temporary_bp,
       {
 	location_spec_up locspec;
 	symbol_name_match_type func_name_match_type
-	  = (qualified != NULL && PyObject_IsTrue (qualified)
+	  = (qualified
 	     ? symbol_name_match_type::FULL
 	     : symbol_name_match_type::WILD);
 
@@ -916,14 +916,15 @@ bppy_init (PyObject *self, PyObject *args, PyObject *kwargs)
   char *label = NULL;
   char *source = NULL;
   char *function = NULL;
-  PyObject * qualified = NULL;
+  PyObject *qualified_obj = nullptr;
+  int qualified = 0;
 
   if (!gdb_PyArg_ParseTupleAndKeywords (args, kwargs, "|siiOOsssOO", keywords,
 					&spec, &type, &access_type,
 					&internal,
 					&temporary, &source,
 					&function, &label, &lineobj,
-					&qualified))
+					&qualified_obj))
     return -1;
 
 
@@ -955,6 +956,13 @@ bppy_init (PyObject *self, PyObject *args, PyObject *kwargs)
 	return -1;
     }
 
+  if (qualified_obj != nullptr)
+    {
+      qualified = PyObject_IsTrue (qualified_obj);
+      if (qualified == -1)
+	return -1;
+    }
+
   if (bppy_init_validate_args (spec, source, function, label, line.get (),
 			       type) == -1)
     return -1;
-- 
2.34.3