From 041489472bfcbea11a71014fd349bee51ab4bc2b Mon Sep 17 00:00:00 2001
From: Jubilee <46493976+workingjubilee@users.noreply.github.com>
Date: Mon, 13 Sep 2021 20:49:27 -0700
Subject: [PATCH] Revert "Fix non-capturing closure return type coercion"

---
 compiler/rustc_typeck/src/check/coercion.rs |  6 ----
 src/test/ui/coercion/issue-88097.rs         | 31 ---------------------
 2 files changed, 37 deletions(-)
 delete mode 100644 src/test/ui/coercion/issue-88097.rs

diff --git a/compiler/rustc_typeck/src/check/coercion.rs b/compiler/rustc_typeck/src/check/coercion.rs
index 6fe96e4cc27b2..3bfab9d513f37 100644
--- a/compiler/rustc_typeck/src/check/coercion.rs
+++ b/compiler/rustc_typeck/src/check/coercion.rs
@@ -1003,12 +1003,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             exprs.len()
         );
 
-        // The following check fixes #88097, where the compiler erroneously
-        // attempted to coerce a closure type to itself via a function pointer.
-        if prev_ty == new_ty {
-            return Ok(prev_ty);
-        }
-
         // Special-case that coercion alone cannot handle:
         // Function items or non-capturing closures of differing IDs or InternalSubsts.
         let (a_sig, b_sig) = {
diff --git a/src/test/ui/coercion/issue-88097.rs b/src/test/ui/coercion/issue-88097.rs
deleted file mode 100644
index e543e1bae9239..0000000000000
--- a/src/test/ui/coercion/issue-88097.rs
+++ /dev/null
@@ -1,31 +0,0 @@
-// In #88097, the compiler attempted to coerce a closure type to itself via
-// a function pointer, which caused an unnecessary error. Check that this
-// behavior has been fixed.
-
-// check-pass
-
-fn peculiar() -> impl Fn(u8) -> u8 {
-    return |x| x + 1
-}
-
-fn peculiar2() -> impl Fn(u8) -> u8 {
-    return |x| x + 1;
-}
-
-fn peculiar3() -> impl Fn(u8) -> u8 {
-    let f = |x| x + 1;
-    return f
-}
-
-fn peculiar4() -> impl Fn(u8) -> u8 {
-    let f = |x| x + 1;
-    f
-}
-
-fn peculiar5() -> impl Fn(u8) -> u8 {
-    let f = |x| x + 1;
-    let g = |x| x + 2;
-    return if true { f } else { g }
-}
-
-fn main() {}