RustPython · youknowone · Jan 2, 2026 · Jan 1, 2026 · Jan 1, 2026 · Jan 1, 2026
diff --git a/Lib/test/test_super.py b/Lib/test/test_super.py
@@ -344,7 +344,6 @@ def test_super_argcount(self):
         with self.assertRaisesRegex(TypeError, "expected at most"):
             super(int, int, int)
 
-    @unittest.expectedFailure # TODO: RUSTPYTHON; AssertionError: "argument 1 must be a type" does not match "Expected type 'type' but 'int' found."
     def test_super_argtype(self):
         with self.assertRaisesRegex(TypeError, "argument 1 must be a type"):
             super(1, int)
@@ -409,7 +408,6 @@ def method(self):
         with self.assertRaisesRegex(AttributeError, "'super' object has no attribute 'msg'"):
             C().method()
 
-    @unittest.expectedFailure # TODO: RUSTPYTHON; AssertionError: "argument 1 must be a type" does not match "Expected type 'type' but 'int' found."
     def test_bad_first_arg(self):
         class C:
             def method(self):

diff --git a/crates/stdlib/src/fcntl.rs b/crates/stdlib/src/fcntl.rs
@@ -92,11 +92,15 @@ mod fcntl {
     #[pyfunction]
     fn ioctl(
         io::Fildes(fd): io::Fildes,
-        request: u32,
+        request: i64,
         arg: OptionalArg<Either<Either<ArgMemoryBuffer, ArgStrOrBytesLike>, i32>>,
         mutate_flag: OptionalArg<bool>,
         vm: &VirtualMachine,
     ) -> PyResult {
+        // Convert to unsigned - handles both positive u32 values and negative i32 values
+        // that represent the same bit pattern (e.g., TIOCSWINSZ on some platforms).
+        // First truncate to u32 (takes lower 32 bits), then zero-extend to c_ulong.
+        let request = (request as u32) as libc::c_ulong;
         let arg = arg.unwrap_or_else(|| Either::B(0));
         match arg {
             Either::A(buf_kind) => {

diff --git a/crates/stdlib/src/ssl.rs b/crates/stdlib/src/ssl.rs
@@ -2293,45 +2293,55 @@ mod _ssl {
 
     // SSLSocket - represents a TLS-wrapped socket
     #[pyattr]
-    #[pyclass(name = "_SSLSocket", module = "ssl")]
+    #[pyclass(name = "_SSLSocket", module = "ssl", traverse)]
     #[derive(Debug, PyPayload)]
     pub(crate) struct PySSLSocket {
         // Underlying socket
         sock: PyObjectRef,
         // SSL context
         context: PyRwLock<PyRef<PySSLContext>>,
         // Server-side or client-side
+        #[pytraverse(skip)]
         server_side: bool,
         // Server hostname for SNI
+        #[pytraverse(skip)]
         server_hostname: PyRwLock<Option<String>>,
         // TLS connection state
+        #[pytraverse(skip)]
         connection: PyMutex<Option<TlsConnection>>,
         // Handshake completed flag
+        #[pytraverse(skip)]
         handshake_done: PyMutex<bool>,
         // Session was reused (for session resumption tracking)
+        #[pytraverse(skip)]
         session_was_reused: PyMutex<bool>,
         // Owner (SSLSocket instance that owns this _SSLSocket)
         owner: PyRwLock<Option<PyObjectRef>>,
         // Session for resumption
         session: PyRwLock<Option<PyObjectRef>>,
         // Verified certificate chain (built during verification)
         #[allow(dead_code)]
+        #[pytraverse(skip)]
         verified_chain: PyRwLock<Option<Vec<CertificateDer<'static>>>>,
         // MemoryBIO mode (optional)
         incoming_bio: Option<PyRef<PyMemoryBIO>>,
         outgoing_bio: Option<PyRef<PyMemoryBIO>>,
         // SNI certificate resolver state (for server-side only)
+        #[pytraverse(skip)]
         sni_state: PyRwLock<Option<Arc<ParkingMutex<SniCertName>>>>,
         // Pending context change (for SNI callback deferred handling)
         pending_context: PyRwLock<Option<PyRef<PySSLContext>>>,
         // Buffer to store ClientHello for connection recreation
+        #[pytraverse(skip)]
         client_hello_buffer: PyMutex<Option<Vec<u8>>>,
         // Shutdown state for tracking close-notify exchange
+        #[pytraverse(skip)]
         shutdown_state: PyMutex<ShutdownState>,
         // Deferred client certificate verification error (for TLS 1.3)
         // Stores error message if client cert verification failed during handshake
         // Error is raised on first I/O operation after handshake
         // Using Arc to share with the certificate verifier
+        #[pytraverse(skip)]
         deferred_cert_error: Arc<ParkingRwLock<Option<String>>>,
     }
 

diff --git a/crates/vm/src/builtins/super.rs b/crates/vm/src/builtins/super.rs
@@ -61,7 +61,7 @@ impl Constructor for PySuper {
 #[derive(FromArgs)]
 pub struct InitArgs {
     #[pyarg(positional, optional)]
-    py_type: OptionalArg<PyTypeRef>,
+    py_type: OptionalArg<PyObjectRef>,
     #[pyarg(positional, optional)]
     py_obj: OptionalArg<PyObjectRef>,
 }
@@ -75,7 +75,10 @@ impl Initializer for PySuper {
         vm: &VirtualMachine,
     ) -> PyResult<()> {
         // Get the type:
-        let (typ, obj) = if let OptionalArg::Present(ty) = py_type {
+        let (typ, obj) = if let OptionalArg::Present(ty_obj) = py_type {
+            let ty = ty_obj
+                .downcast::<PyType>()
+                .map_err(|_| vm.new_type_error("super() argument 1 must be a type"))?;
             (ty, py_obj.unwrap_or_none(vm))
         } else {
             let frame = vm

diff --git a/crates/vm/src/stdlib/thread.rs b/crates/vm/src/stdlib/thread.rs
@@ -400,6 +400,138 @@ pub(crate) mod _thread {
         vm.state.thread_count.load()
     }
 
+    /// ExceptHookArgs - simple class to hold exception hook arguments
+    /// This allows threading.py to import _excepthook and _ExceptHookArgs from _thread
+    #[pyattr]
+    #[pyclass(module = "_thread", name = "_ExceptHookArgs")]
+    #[derive(Debug, PyPayload)]
+    struct ExceptHookArgs {
+        exc_type: crate::PyObjectRef,
+        exc_value: crate::PyObjectRef,
+        exc_traceback: crate::PyObjectRef,
+        thread: crate::PyObjectRef,
+    }
+
+    #[pyclass(with(Constructor))]
+    impl ExceptHookArgs {
+        #[pygetset]
+        fn exc_type(&self) -> crate::PyObjectRef {
+            self.exc_type.clone()
+        }
+
+        #[pygetset]
+        fn exc_value(&self) -> crate::PyObjectRef {
+            self.exc_value.clone()
+        }
+
+        #[pygetset]
+        fn exc_traceback(&self) -> crate::PyObjectRef {
+            self.exc_traceback.clone()
+        }
+
+        #[pygetset]
+        fn thread(&self) -> crate::PyObjectRef {
+            self.thread.clone()
+        }
+    }
+
+    impl Constructor for ExceptHookArgs {
+        // Takes a single iterable argument like namedtuple
+        type Args = (crate::PyObjectRef,);
+
+        fn py_new(_cls: &Py<PyType>, args: Self::Args, vm: &VirtualMachine) -> PyResult<Self> {
+            // Convert the argument to a list/tuple and extract elements
+            let seq: Vec<crate::PyObjectRef> = args.0.try_to_value(vm)?;
+            if seq.len() != 4 {
+                return Err(vm.new_type_error(format!(
+                    "_ExceptHookArgs expected 4 arguments, got {}",
+                    seq.len()
+                )));
+            }
+            Ok(Self {
+                exc_type: seq[0].clone(),
+                exc_value: seq[1].clone(),
+                exc_traceback: seq[2].clone(),
+                thread: seq[3].clone(),
+            })
+        }
+    }
+
+    /// Handle uncaught exception in Thread.run()
+    #[pyfunction]
+    fn _excepthook(args: crate::PyObjectRef, vm: &VirtualMachine) -> PyResult<()> {
+        // Type check: args must be _ExceptHookArgs
+        let args = args.downcast::<ExceptHookArgs>().map_err(|_| {
+            vm.new_type_error(
+                "_thread._excepthook argument type must be _ExceptHookArgs".to_owned(),
+            )
+        })?;
+
+        let exc_type = args.exc_type.clone();
+        let exc_value = args.exc_value.clone();
+        let exc_traceback = args.exc_traceback.clone();
+        let thread = args.thread.clone();
+
+        // Silently ignore SystemExit (identity check)
+        if exc_type.is(vm.ctx.exceptions.system_exit.as_ref()) {
+            return Ok(());
+        }
+
+        // Get stderr - fall back to thread._stderr if sys.stderr is None
+        let file = match vm.sys_module.get_attr("stderr", vm) {
+            Ok(stderr) if !vm.is_none(&stderr) => stderr,
+            _ => {
+                if vm.is_none(&thread) {
+                    // do nothing if sys.stderr is None and thread is None
+                    return Ok(());
+                }
+                let thread_stderr = thread.get_attr("_stderr", vm)?;
+                if vm.is_none(&thread_stderr) {
+                    // do nothing if sys.stderr is None and sys.stderr was None
+                    // when the thread was created
+                    return Ok(());
+                }
+                thread_stderr
+            }
+        };
+
+        // Print "Exception in thread {thread.name}:"
+        let thread_name = if !vm.is_none(&thread) {
+            thread
+                .get_attr("name", vm)
+                .ok()
+                .and_then(|n| n.str(vm).ok())
+                .map(|s| s.as_str().to_owned())
+        } else {
+            None
+        };
+        let name = thread_name.unwrap_or_else(|| format!("{}", get_ident()));
+
+        let _ = vm.call_method(
+            &file,
+            "write",
+            (format!("Exception in thread {}:\n", name),),
+        );
+
+        // Display the traceback
+        if let Ok(traceback_mod) = vm.import("traceback", 0)
+            && let Ok(print_exc) = traceback_mod.get_attr("print_exception", vm)
+        {
+            use crate::function::KwArgs;
+            let kwargs: KwArgs = vec![("file".to_owned(), file.clone())]
+                .into_iter()
+                .collect();
+            let _ = print_exc.call_with_args(
+                crate::function::FuncArgs::new(vec![exc_type, exc_value, exc_traceback], kwargs),
+                vm,
+            );
+        }
+
+        // Flush file
+        let _ = vm.call_method(&file, "flush", ());
+        Ok(())
+    }
+
     #[pyattr]
     #[pyclass(module = "thread", name = "_local")]
     #[derive(Debug, PyPayload)]

diff --git a/crates/vm/src/warn.rs b/crates/vm/src/warn.rs
@@ -404,8 +404,20 @@ fn setup_context(
 
     let (globals, filename, lineno) = if let Some(f) = f {
         (f.globals.clone(), f.code.source_path, f.f_lineno())
+    } else if let Some(frame) = vm.current_frame() {
+        // We have a frame but it wasn't found during stack walking
+        (frame.globals.clone(), vm.ctx.intern_str("<sys>"), 1)
     } else {
-        (vm.current_globals().clone(), vm.ctx.intern_str("sys"), 1)
+        // No frames on the stack - use sys.__dict__ (interp->sysdict)
+        let globals = vm
+            .sys_module
+            .as_object()
+            .get_attr(identifier!(vm, __dict__), vm)
+            .and_then(|d| {
+                d.downcast::<crate::builtins::PyDict>()
+                    .map_err(|_| vm.new_type_error("sys.__dict__ is not a dictionary"))
+            })?;
+        (globals, vm.ctx.intern_str("<sys>"), 0)
     };
 
     let registry = if let Ok(registry) = globals.get_item(__warningregistry__, vm) {