Readd os::cygwin::raw as pub(crate)

library/std/src/os/cygwin/mod.rs

@@ -1,3 +1,4 @@
 //! Cygwin-specific definitions
 #![stable(feature = "raw_ext", since = "1.1.0")]
 pub mod fs;
+pub(crate) mod raw;

library/std/src/os/cygwin/raw.rs

@@ -0,0 +1,4 @@
+//! Cygwin-specific raw type definitions.
+
+#[stable(feature = "raw_ext", since = "1.1.0")]
+pub use libc::{blkcnt_t, blksize_t, dev_t, ino_t, mode_t, nlink_t, off_t, pthread_t, time_t};

library/std/src/sys/pal/unix/thread.rs

@@ -344,7 +344,6 @@ impl Drop for Thread {
     target_os = "illumos",
     target_os = "vxworks",
     target_vendor = "apple",
-    target_os = "cygwin",
 ))]
 fn truncate_cstr<const MAX_WITH_NUL: usize>(cstr: &CStr) -> [libc::c_char; MAX_WITH_NUL] {
     let mut result = [0; MAX_WITH_NUL];