std: Re-enable at_exit()

The new semantics of this function are that the callbacks are run when the *main
thread* exits, not when all threads have exited. This implies that other threads
may still be running when the `at_exit` callbacks are invoked and users need to
be prepared for this situation.

Users in the standard library have been audited in accordance to these new rules
as well.

Closes #20012

1 files changed, 4 insertions, 8 deletions

diff --git a/src/libstd/sys/windows/fs.rs b/src/libstd/sys/windows/fs.rs
index 3ad439078b9..523d9e9a3c2 100644
--- a/src/libstd/sys/windows/fs.rs
+++ b/src/libstd/sys/windows/fs.rs
@@ -10,21 +10,17 @@
 
 //! Blocking Windows-based file I/O
 
-use alloc::arc::Arc;
 use libc::{mod, c_int};
 
-use c_str::CString;
+use io;
 use mem;
-use sys::os::fill_utf16_buf_and_decode;
-use path;
 use ptr;
-use str;
-use io;
+use sys::os::fill_utf16_buf_and_decode;
 
 use prelude::*;
 use sys;
 use sys::os;
-use sys_common::{keep_going, eof, mkerr_libc};
+use sys_common::{unimpl, mkerr_libc};
 
 use io::{FilePermission, Write, UnstableFileStat, Open, FileAccess, FileMode};
 use io::{IoResult, IoError, FileStat, SeekStyle};
@@ -445,7 +441,7 @@ pub fn stat(p: &Path) -> IoResult<FileStat> {
 // FIXME: move this to platform-specific modules (for now)?
 pub fn lstat(_p: &Path) -> IoResult<FileStat> {
     // FIXME: implementation is missing
-    Err(super::unimpl())
+    Err(unimpl())
 }
 
 pub fn utime(p: &Path, atime: u64, mtime: u64) -> IoResult<()> {