Rollup merge of #89508 - jhpratt:stabilize-const_panic, r=joshtriplett

Stabilize `const_panic`

Closes #51999

FCP completed in #89006

```@rustbot``` label +A-const-eval +A-const-fn +T-lang

cc ```@oli-obk``` for review (not `r?`'ing as not on lang team)

2 files changed, 0 insertions, 19 deletions

diff --git a/compiler/rustc_const_eval/src/transform/check_consts/check.rs b/compiler/rustc_const_eval/src/transform/check_consts/check.rs
index 57d92005a56..fd5cd269a3a 100644
--- a/compiler/rustc_const_eval/src/transform/check_consts/check.rs
+++ b/compiler/rustc_const_eval/src/transform/check_consts/check.rs
@@ -887,8 +887,6 @@ impl Visitor<'tcx> for Checker<'mir, 'tcx> {
 
                 // At this point, we are calling a function, `callee`, whose `DefId` is known...
                 if is_lang_panic_fn(tcx, callee) {
-                    self.check_op(ops::Panic);
-
                     // `begin_panic` and `panic_display` are generic functions that accept
                     // types other than str. Check to enforce that only str can be used in
                     // const-eval.
diff --git a/compiler/rustc_const_eval/src/transform/check_consts/ops.rs b/compiler/rustc_const_eval/src/transform/check_consts/ops.rs
index a39fca0d8be..f08f51ec627 100644
--- a/compiler/rustc_const_eval/src/transform/check_consts/ops.rs
+++ b/compiler/rustc_const_eval/src/transform/check_consts/ops.rs
@@ -368,23 +368,6 @@ impl NonConstOp for MutDeref {
     }
 }
 
-#[derive(Debug)]
-pub struct Panic;
-impl NonConstOp for Panic {
-    fn status_in_item(&self, _: &ConstCx<'_, '_>) -> Status {
-        Status::Unstable(sym::const_panic)
-    }
-
-    fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, span: Span) -> DiagnosticBuilder<'tcx> {
-        feature_err(
-            &ccx.tcx.sess.parse_sess,
-            sym::const_panic,
-            span,
-            &format!("panicking in {}s is unstable", ccx.const_kind()),
-        )
-    }
-}
-
 /// A call to a `panic()` lang item where the first argument is _not_ a `&str`.
 #[derive(Debug)]
 pub struct PanicNonStr;