rustc: Implement the #[global_allocator] attribute

This PR is an implementation of [RFC 1974] which specifies a new method of
defining a global allocator for a program. This obsoletes the old
`#![allocator]` attribute and also removes support for it.

[RFC 1974]: https://github.com/rust-lang/rfcs/pull/197

The new `#[global_allocator]` attribute solves many issues encountered with the
`#![allocator]` attribute such as composition and restrictions on the crate
graph itself. The compiler now has much more control over the ABI of the
allocator and how it's implemented, allowing much more freedom in terms of how
this feature is implemented.

cc #27389

1 files changed, 0 insertions, 18 deletions

diff --git a/src/libstd/sys/windows/mod.rs b/src/libstd/sys/windows/mod.rs
index 840e7fdfc9b..ee58efc5144 100644
--- a/src/libstd/sys/windows/mod.rs
+++ b/src/libstd/sys/windows/mod.rs
@@ -47,24 +47,6 @@ pub mod stdio;
 
 #[cfg(not(test))]
 pub fn init() {
-    ::alloc::oom::set_oom_handler(oom_handler);
-
-    // See comment in sys/unix/mod.rs
-    fn oom_handler() -> ! {
-        use intrinsics;
-        use ptr;
-        let msg = "fatal runtime error: out of memory\n";
-        unsafe {
-            // WriteFile silently fails if it is passed an invalid handle, so
-            // there is no need to check the result of GetStdHandle.
-            c::WriteFile(c::GetStdHandle(c::STD_ERROR_HANDLE),
-                         msg.as_ptr() as c::LPVOID,
-                         msg.len() as c::DWORD,
-                         ptr::null_mut(),
-                         ptr::null_mut());
-            intrinsics::abort();
-        }
-    }
 }
 
 pub fn decode_error_kind(errno: i32) -> ErrorKind {