Allow conversion of 128-bit integers to Python
Currently, trying to convert a 128-bit integer from a gdb.Value to a
Python integer will fail. This is surprising because Python uses
bigints internally.
The bug here is that valpy_long uses value_as_long, which fails for
anything wider than LONGEST. This patch fixes the problem by using
the recommended Python API.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=33366
Approved-By: Simon Marchi <simon.marchi@efficios.com>
diff --git a/gdb/python/py-value.c b/gdb/python/py-value.c
index 833ce26..7cde7a5 100644
--- a/gdb/python/py-value.c
+++ b/gdb/python/py-value.c
@@ -1866,7 +1866,7 @@ valpy_long (PyObject *self)
{
struct value *value = ((value_object *) self)->value;
struct type *type = value->type ();
- LONGEST l = 0;
+ PyObject *result;
try
{
@@ -1882,17 +1882,57 @@ valpy_long (PyObject *self)
&& type->code () != TYPE_CODE_PTR)
error (_("Cannot convert value to long."));
- l = value_as_long (value);
+ gdb::array_view<const gdb_byte> contents = value->contents ();
+#if PY_VERSION_HEX >= 0x030d0000
+ int flags = (type_byte_order (type) == BFD_ENDIAN_BIG
+ ? Py_ASNATIVEBYTES_BIG_ENDIAN
+ : Py_ASNATIVEBYTES_LITTLE_ENDIAN);
+ if (type->is_unsigned ())
+ flags |= Py_ASNATIVEBYTES_UNSIGNED_BUFFER;
+ result = PyLong_FromNativeBytes (contents.data (), contents.size (),
+ flags);
+#else
+ /* Here we construct a call to "int.from_bytes", passing in the
+ appropriate arguments. We need a somewhat roundabout
+ approach because int.from_bytes requires "signed" to be a
+ keyword arg. */
+
+ /* PyObject_Call requires a tuple argument. */
+ gdbpy_ref<> empty_tuple (PyTuple_New (0));
+ if (empty_tuple == nullptr)
+ return nullptr;
+
+ /* Since we need a dictionary anyway, we pass all arguments as
+ keywords, building the dictionary here. */
+ gdbpy_ref<> args
+ (Py_BuildValue ("{sy#sssO}",
+ "bytes", contents.data (),
+ (Py_ssize_t) contents.size (),
+ "byteorder",
+ (type_byte_order (type) == BFD_ENDIAN_BIG
+ ? "big" : "little"),
+ "signed",
+ type->is_unsigned ()
+ ? Py_False : Py_True));
+ if (args == nullptr)
+ return nullptr;
+
+ /* Find the "int.from_bytes" callable. */
+ gdbpy_ref<> callable (PyObject_GetAttrString ((PyObject *) &PyLong_Type,
+ "from_bytes"));
+ if (callable == nullptr)
+ return nullptr;
+
+ result = PyObject_Call (callable.get (), empty_tuple.get (),
+ args.get ());
+#endif
}
catch (const gdb_exception &except)
{
return gdbpy_handle_gdb_exception (nullptr, except);
}
- if (type->is_unsigned ())
- return gdb_py_object_from_ulongest (l).release ();
- else
- return gdb_py_object_from_longest (l).release ();
+ return result;
}
/* Implements conversion to float. */
diff --git a/gdb/testsuite/gdb.python/py-value.exp b/gdb/testsuite/gdb.python/py-value.exp
index ab49f2d..089bf75 100644
--- a/gdb/testsuite/gdb.python/py-value.exp
+++ b/gdb/testsuite/gdb.python/py-value.exp
@@ -844,3 +844,15 @@
test_subscript_regression "${binfile}-cxx" "c++"
}
}
+
+if {[allow_rust_tests]} {
+ gdb_test "set lang rust"
+
+ set cst 0x80000000000000000000000000000000
+ gdb_test "python print(int(gdb.parse_and_eval('${cst}u128')))" \
+ "170141183460469231731687303715884105728" \
+ "convert 128 bit unsigned constant to python int"
+ gdb_test "python print(int(gdb.parse_and_eval('${cst}i128')))" \
+ "-170141183460469231731687303715884105728" \
+ "convert 128 bit signed constant to python int"
+}
