1 files changed, 11 insertions, 0 deletions
diff --git a/thread_win32.c b/thread_win32.c
index a810fb3622..7c31a3f70e 100644
--- a/thread_win32.c
+++ b/thread_win32.c
@@ -532,8 +532,19 @@ native_thread_apply_priority(rb_thread_t *th)
 static void
 ubf_handle(void *ptr)
 {
+    static int checked = 0;
+    typedef BOOL (WINAPI *cancel_io_func_t)(HANDLE);
+    static cancel_io_func_t cancel_func = NULL;
     rb_thread_t *th = (rb_thread_t *)ptr;
     thread_debug("ubf_handle: %p\n", th);
+
+    if (!checked) {
+	cancel_func = (cancel_io_func_t)GetProcAddress(GetModuleHandle("kernel32"), "CancelSynchronousIo");
+	checked = 1;
+    }
+    if (cancel_func)
+	cancel_func((HANDLE)th->thread_id);
+
     w32_set_event(th->native_thread_data.interrupt_event);
 }