From 6d4b7fe9ed055c086c7843c9ce07c1a5a19e245b Mon Sep 17 00:00:00 2001
From: Maybe Waffle <waffle.lapkin@gmail.com>
Date: Thu, 20 Apr 2023 12:41:46 +0000
Subject: [PATCH] Remove an unused `&[Ty]` <-> `&[GenericArg]`

---
 compiler/rustc_middle/src/ty/subst.rs | 13 -------------
 1 file changed, 13 deletions(-)

diff --git a/compiler/rustc_middle/src/ty/subst.rs b/compiler/rustc_middle/src/ty/subst.rs
index da3cd27f388..ee078a9abf2 100644
--- a/compiler/rustc_middle/src/ty/subst.rs
+++ b/compiler/rustc_middle/src/ty/subst.rs
@@ -21,7 +21,6 @@
 use std::mem;
 use std::num::NonZeroUsize;
 use std::ops::{ControlFlow, Deref};
-use std::slice;
 
 /// An entity in the Rust type system, which can be one of
 /// several kinds (types, lifetimes, and consts).
@@ -55,18 +54,6 @@ pub enum GenericArgKind<'tcx> {
     Const(ty::Const<'tcx>),
 }
 
-/// This function goes from `&'a [Ty<'tcx>]` to `&'a [GenericArg<'tcx>]`
-///
-/// This is sound as, for types, `GenericArg` is just
-/// `NonZeroUsize::new_unchecked(ty as *const _ as usize)` as
-/// long as we use `0` for the `TYPE_TAG`.
-pub fn ty_slice_as_generic_args<'a, 'tcx>(ts: &'a [Ty<'tcx>]) -> &'a [GenericArg<'tcx>] {
-    assert_eq!(TYPE_TAG, 0);
-    // SAFETY: the whole slice is valid and immutable.
-    // `Ty` and `GenericArg` is explained above.
-    unsafe { slice::from_raw_parts(ts.as_ptr().cast(), ts.len()) }
-}
-
 impl<'tcx> GenericArgKind<'tcx> {
     #[inline]
     fn pack(self) -> GenericArg<'tcx> {