RustPython
diff --git a/‎crates/host_env/src/ctypes.rs‎
Lines changed: 16 additions & 1 deletion b/‎crates/host_env/src/ctypes.rs‎
Lines changed: 16 additions & 1 deletion
diff --git a/‎crates/stdlib/Cargo.toml‎
Lines changed: 1 addition & 1 deletion b/‎crates/stdlib/Cargo.toml‎
Lines changed: 1 addition & 1 deletion
diff --git a/‎crates/vm/src/stdlib/_ctypes.rs‎
Lines changed: 4 additions & 2 deletions b/‎crates/vm/src/stdlib/_ctypes.rs‎
Lines changed: 4 additions & 2 deletions
diff --git a/‎crates/vm/src/stdlib/_thread.rs‎
Lines changed: 34 additions & 17 deletions b/‎crates/vm/src/stdlib/_thread.rs‎
Lines changed: 34 additions & 17 deletions
@@ -2921,7 +2921,22 @@ fn lookup_raw_windows_symbol(
             .map_err(|err| LookupSymbolError::Load(err.to_string()))?;
         owned.as_c_str()
     };
-    get_proc_address(handle as _, name).ok_or(LookupSymbolError::LibraryNotFound)
+    match get_proc_address(handle as _, name) {
+        Some(addr) => Ok(addr),
+        None => {
+            // A valid LoadLibraryExW handle with no such export is a missing
+            // symbol, not a missing library. GetProcAddress sets
+            // ERROR_PROC_NOT_FOUND (127); invalid/unloaded modules typically
+            // set ERROR_INVALID_HANDLE (6) or ERROR_MOD_NOT_FOUND (126).
+            match std::io::Error::last_os_error().raw_os_error() {
+                Some(6 | 126) => Err(LookupSymbolError::LibraryNotFound),
+                _ => Err(LookupSymbolError::Load(format!(
+                    "function '{}' not found",
+                    name.to_string_lossy()
+                ))),
+            }
+        }
+    }
 }
 
 #[cfg(all(unix, not(target_os = "wasi")))]
 
@@ -18,7 +18,7 @@ threading = ["rustpython-common/threading", "rustpython-vm/threading"]
 sqlite = ["dep:libsqlite3-sys"]
 # SSL backends
 ssl = ["rustpython-host_env/ssl"]
-ssl-rustls = ["__ssl-rustls", "rustls/custom-provider"]
+ssl-rustls = ["__ssl-rustls", "host_env", "rustls/custom-provider"]
 ssl-openssl = ["ssl", "host_env", "openssl", "openssl-sys", "foreign-types-shared", "rustpython-host_env/native-certs"]
 ssl-openssl-vendor = ["ssl-openssl", "openssl/vendored"]
 tkinter = ["dep:tk-sys", "dep:tcl-sys", "dep:widestring"]
 
@@ -94,6 +94,8 @@ pub(crate) mod _ctypes {
     use super::{PyCArray, PyCData, PyCPointer, PyCSimple, PyCStructure, PyCUnion};
     use crate::builtins::{PyType, PyTypeRef};
     use crate::class::StaticType;
+    #[cfg(windows)]
+    use crate::convert::ToPyException;
     use crate::convert::ToPyObject;
     use crate::function::{Either, OptionalArg};
     use crate::types::Representable;
@@ -427,7 +429,7 @@ pub(crate) mod _ctypes {
         let flags = load_flags.unwrap_or(0) as u32;
         rustpython_host_env::ctypes::load_library_ex_w(&wide, flags)
             .map(|module| module as usize)
-            .map_err(|error| vm.new_os_error(error.to_string()))
+            .map_err(|error| error.to_pyexception(vm))
     }
 
     #[cfg(not(windows))]
@@ -463,7 +465,7 @@ pub(crate) mod _ctypes {
     #[pyfunction(name = "FreeLibrary")]
     fn free_library(handle: usize, vm: &VirtualMachine) -> PyResult<()> {
         rustpython_host_env::ctypes::free_library(handle as _)
-            .map_err(|error| vm.new_os_error(error.to_string()))
+            .map_err(|error| error.to_pyexception(vm))
     }
 
     #[cfg(not(windows))]
 
@@ -410,36 +410,57 @@ pub(crate) mod _thread {
         vm.state.stop_the_world.reset_stats();
     }
 
-    #[cfg(any(unix, windows))]
+    #[cfg(any(windows, target_os = "linux", target_os = "macos"))]
     #[pyattr]
     const _NAME_MAXLEN: usize = host_thread::NAME_MAXLEN;
 
+    /// Truncate a Windows thread name to `_NAME_MAXLEN` UTF-16 code units,
+    /// dropping a trailing non-BMP character that would not fit as a pair.
+    #[cfg(windows)]
+    fn truncate_thread_name_wide(name: &crate::common::wtf8::Wtf8) -> Vec<u16> {
+        let encoded: Vec<u16> = name.encode_wide().collect();
+        let mut units = Vec::new();
+        let mut i = 0;
+        while i < encoded.len() {
+            let unit = encoded[i];
+            if unit == 0 {
+                break;
+            }
+            let width = match encoded.get(i + 1) {
+                Some(&lo)
+                    if (0xD800..=0xDBFF).contains(&unit) && (0xDC00..=0xDFFF).contains(&lo) =>
+                {
+                    2
+                }
+                _ => 1,
+            };
+            if units.len() + width > host_thread::NAME_MAXLEN {
+                break;
+            }
+            units.extend_from_slice(&encoded[i..i + width]);
+            i += width;
+        }
+        units.push(0);
+        units
+    }
+
+    #[cfg(any(windows, target_os = "linux", target_os = "macos"))]
     #[pyfunction]
     fn set_name(name: PyStrRef, vm: &VirtualMachine) -> PyResult<()> {
         #[cfg(windows)]
         {
-            let mut units = Vec::new();
-            for unit in name.as_wtf8().encode_wide() {
-                if unit == 0 || units.len() >= host_thread::NAME_MAXLEN {
-                    break;
-                }
-                units.push(unit);
-            }
-            units.push(0);
+            let units = truncate_thread_name_wide(name.as_wtf8());
             host_thread::set_current_thread_name_wide(&units).map_err(|e| e.to_pyexception(vm))?;
         }
         #[cfg(any(target_os = "linux", target_os = "macos"))]
         {
             let os_name = vm.fsencode(&name)?;
             host_thread::set_current_thread_name_bytes(os_name.as_encoded_bytes());
         }
-        #[cfg(not(any(windows, target_os = "linux", target_os = "macos")))]
-        {
-            let _ = (name, vm);
-        }
         Ok(())
     }
 
+    #[cfg(any(windows, target_os = "linux", target_os = "macos"))]
     #[pyfunction(name = "_get_name")]
     fn get_name(vm: &VirtualMachine) -> PyResult {
         #[cfg(windows)]
@@ -456,10 +477,6 @@ pub(crate) mod _thread {
             let os = unsafe { std::ffi::OsString::from_encoded_bytes_unchecked(bytes) };
             Ok(vm.fsdecode(os).into())
         }
-        #[cfg(not(any(windows, target_os = "linux", target_os = "macos")))]
-        {
-            Ok(vm.ctx.new_str("").into())
-        }
     }
 
     /// Get OS-level thread ID (pthread_self on Unix, GetCurrentThreadId on Windows)