RustPython · youknowone · May 17, 2026 · May 17, 2026
diff --git a/Lib/ctypes/__init__.py b/Lib/ctypes/__init__.py
@@ -470,6 +470,8 @@ def _load_library(self, name, mode, handle, winmode):
                 if name and name.endswith(")") and ".a(" in name:
                     mode |= _os.RTLD_MEMBER | _os.RTLD_NOW
             self._name = name
+            if handle is not None:
+                return handle
             return _dlopen(name, mode)
 
     def __repr__(self):

diff --git a/Lib/ctypes/util.py b/Lib/ctypes/util.py
@@ -85,24 +85,30 @@ def find_library(name):
         wintypes.DWORD,
     )
 
-    _psapi = ctypes.WinDLL('psapi', use_last_error=True)
-    _enum_process_modules = _psapi["EnumProcessModules"]
-    _enum_process_modules.restype = wintypes.BOOL
-    _enum_process_modules.argtypes = (
-        wintypes.HANDLE,
-        ctypes.POINTER(wintypes.HMODULE),
-        wintypes.DWORD,
-        wintypes.LPDWORD,
-    )
+    # gh-145307: We defer loading psapi.dll until _get_module_handles is called.
+    # Loading additional DLLs at startup for functionality that may never be
+    # used is wasteful.
+    _enum_process_modules = None
 
     def _get_module_filename(module: wintypes.HMODULE):
         name = (wintypes.WCHAR * 32767)() # UNICODE_STRING_MAX_CHARS
         if _k32_get_module_file_name(module, name, len(name)):
             return name.value
         return None
 
-
     def _get_module_handles():
+        global _enum_process_modules
+        if _enum_process_modules is None:
+            _psapi = ctypes.WinDLL('psapi', use_last_error=True)
+            _enum_process_modules = _psapi["EnumProcessModules"]
+            _enum_process_modules.restype = wintypes.BOOL
+            _enum_process_modules.argtypes = (
+                wintypes.HANDLE,
+                ctypes.POINTER(wintypes.HMODULE),
+                wintypes.DWORD,
+                wintypes.LPDWORD,
+            )
+
         process = _get_current_process()
         space_needed = wintypes.DWORD()
         n = 1024

diff --git a/Lib/test/test_ctypes/test_byteswap.py b/Lib/test/test_ctypes/test_byteswap.py
@@ -166,6 +166,48 @@ def test_endian_double(self):
         self.assertEqual(s.value, math.pi)
         self.assertEqual(bin(struct.pack(">d", math.pi)), bin(s))
 
+    @unittest.skipUnless(hasattr(ctypes, 'c_float_complex'), "No complex types")
+    def test_endian_float_complex(self):
+        c_float_complex = ctypes.c_float_complex
+        if sys.byteorder == "little":
+            self.assertIs(c_float_complex.__ctype_le__, c_float_complex)
+            self.assertIs(c_float_complex.__ctype_be__.__ctype_le__,
+                          c_float_complex)
+        else:
+            self.assertIs(c_float_complex.__ctype_be__, c_float_complex)
+            self.assertIs(c_float_complex.__ctype_le__.__ctype_be__,
+                          c_float_complex)
+        s = c_float_complex(math.pi+1j)
+        self.assertEqual(bin(struct.pack("F", math.pi+1j)), bin(s))
+        self.assertAlmostEqual(s.value, math.pi+1j, places=6)
+        s = c_float_complex.__ctype_le__(math.pi+1j)
+        self.assertAlmostEqual(s.value, math.pi+1j, places=6)
+        self.assertEqual(bin(struct.pack("<F", math.pi+1j)), bin(s))
+        s = c_float_complex.__ctype_be__(math.pi+1j)
+        self.assertAlmostEqual(s.value, math.pi+1j, places=6)
+        self.assertEqual(bin(struct.pack(">F", math.pi+1j)), bin(s))
+
+    @unittest.skipUnless(hasattr(ctypes, 'c_double_complex'), "No complex types")
+    def test_endian_double_complex(self):
+        c_double_complex = ctypes.c_double_complex
+        if sys.byteorder == "little":
+            self.assertIs(c_double_complex.__ctype_le__, c_double_complex)
+            self.assertIs(c_double_complex.__ctype_be__.__ctype_le__,
+                          c_double_complex)
+        else:
+            self.assertIs(c_double_complex.__ctype_be__, c_double_complex)
+            self.assertIs(c_double_complex.__ctype_le__.__ctype_be__,
+                          c_double_complex)
+        s = c_double_complex(math.pi+1j)
+        self.assertEqual(bin(struct.pack("D", math.pi+1j)), bin(s))
+        self.assertAlmostEqual(s.value, math.pi+1j, places=6)
+        s = c_double_complex.__ctype_le__(math.pi+1j)
+        self.assertAlmostEqual(s.value, math.pi+1j, places=6)
+        self.assertEqual(bin(struct.pack("<D", math.pi+1j)), bin(s))
+        s = c_double_complex.__ctype_be__(math.pi+1j)
+        self.assertAlmostEqual(s.value, math.pi+1j, places=6)
+        self.assertEqual(bin(struct.pack(">D", math.pi+1j)), bin(s))
+
     def test_endian_other(self):
         self.assertIs(c_byte.__ctype_le__, c_byte)
         self.assertIs(c_byte.__ctype_be__, c_byte)

diff --git a/Lib/test/test_ctypes/test_dllist.py b/Lib/test/test_ctypes/test_dllist.py
@@ -26,7 +26,6 @@
 )
 class ListSharedLibraries(unittest.TestCase):
 
-    # TODO: RUSTPYTHON
     @unittest.skipIf(not APPLE, "TODO: RUSTPYTHON")
     def test_lists_system(self):
         dlls = ctypes.util.dllist()
@@ -36,8 +35,7 @@ def test_lists_system(self):
             any(lib in dll for dll in dlls for lib in KNOWN_LIBRARIES), f"loaded={dlls}"
         )
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
+    @unittest.expectedFailure  # TODO: RUSTPYTHON
     def test_lists_updates(self):
         dlls = ctypes.util.dllist()
 

diff --git a/Lib/test/test_ctypes/test_loading.py b/Lib/test/test_ctypes/test_loading.py
@@ -106,6 +106,14 @@ def test_load_without_name_and_with_handle(self):
         lib = ctypes.WinDLL(name=None, handle=handle)
         self.assertIs(handle, lib._handle)
 
+    @unittest.skipIf(os.name == "nt", 'POSIX-specific test')
+    @unittest.skipIf(libc_name is None, 'could not find libc')
+    def test_load_without_name_and_with_handle_posix(self):
+        lib1 = CDLL(libc_name)
+        handle = lib1._handle
+        lib2 = CDLL(name=None, handle=handle)
+        self.assertIs(lib2._handle, handle)
+
     @unittest.skipUnless(os.name == "nt", 'Windows-specific test')
     def test_1703286_A(self):
         # On winXP 64-bit, advapi32 loads at an address that does

diff --git a/Lib/test/test_ctypes/test_python_api.py b/Lib/test/test_ctypes/test_python_api.py
@@ -7,8 +7,7 @@
 
 
 class PythonAPITestCase(unittest.TestCase):
-    # TODO: RUSTPYTHON - requires pythonapi (Python C API)
-    @unittest.expectedFailure
+    @unittest.expectedFailure  # TODO: RUSTPYTHON; - requires pythonapi (Python C API)
     def test_PyBytes_FromStringAndSize(self):
         PyBytes_FromStringAndSize = pythonapi.PyBytes_FromStringAndSize
 
@@ -59,8 +58,7 @@ def test_PyObj_FromPtr(self):
         del pyobj
         self.assertEqual(sys.getrefcount(s), ref)
 
-    # TODO: RUSTPYTHON - requires pythonapi (Python C API)
-    @unittest.expectedFailure
+    @unittest.expectedFailure  # TODO: RUSTPYTHON; - requires pythonapi (Python C API)
     def test_PyOS_snprintf(self):
         PyOS_snprintf = pythonapi.PyOS_snprintf
         PyOS_snprintf.argtypes = POINTER(c_char), c_size_t, c_char_p

diff --git a/Lib/test/test_ctypes/test_values.py b/Lib/test/test_ctypes/test_values.py
@@ -39,17 +39,15 @@ def test_undefined(self):
 class PythonValuesTestCase(unittest.TestCase):
     """This test only works when python itself is a dll/shared library"""
 
-    # TODO: RUSTPYTHON - requires pythonapi (Python C API)
-    @unittest.expectedFailure
+    @unittest.expectedFailure  # TODO: RUSTPYTHON; - requires pythonapi (Python C API)
     def test_optimizeflag(self):
         # This test accesses the Py_OptimizeFlag integer, which is
         # exported by the Python dll and should match the sys.flags value
 
         opt = c_int.in_dll(pythonapi, "Py_OptimizeFlag").value
         self.assertEqual(opt, sys.flags.optimize)
 
-    # TODO: RUSTPYTHON - requires pythonapi (Python C API)
-    @unittest.expectedFailure
+    @unittest.expectedFailure  # TODO: RUSTPYTHON; - requires pythonapi (Python C API)
     @thread_unsafe('overrides frozen modules')
     def test_frozentable(self):
         # Python exports a PyImport_FrozenModules symbol. This is a

diff --git a/Lib/test/test_ctypes/test_win32.py b/Lib/test/test_ctypes/test_win32.py
@@ -13,8 +13,7 @@
 
 @unittest.skipUnless(sys.platform == "win32", 'Windows-specific test')
 class FunctionCallTestCase(unittest.TestCase):
-    # TODO: RUSTPYTHON: SEH not implemented, crashes with STATUS_ACCESS_VIOLATION
-    @unittest.skip("TODO: RUSTPYTHON")
+    @unittest.skip("TODO: RUSTPYTHON; SEH not implemented, crashes with STATUS_ACCESS_VIOLATION")
     @unittest.skipUnless('MSC' in sys.version, "SEH only supported by MSC")
     @unittest.skipIf(sys.executable.lower().endswith('_d.exe'),
                      "SEH not enabled in debug builds")