Remove CastCheckResult since it's unused

compiler/rustc_hir_analysis/src/check/cast.rs

@@ -203,28 +203,8 @@ fn make_invalid_casting_error<'a, 'tcx>(
     )
 }
 
-pub enum CastCheckResult<'tcx> {
-    Ok,
-    Deferred(CastCheck<'tcx>),
-    Err(ErrorGuaranteed),
-}
-
-pub fn check_cast<'tcx>(
-    fcx: &FnCtxt<'_, 'tcx>,
-    expr: &'tcx hir::Expr<'tcx>,
-    expr_ty: Ty<'tcx>,
-    cast_ty: Ty<'tcx>,
-    cast_span: Span,
-    span: Span,
-) -> CastCheckResult<'tcx> {
-    match CastCheck::new(fcx, expr, expr_ty, cast_ty, cast_span, span) {
-        Ok(check) => CastCheckResult::Deferred(check),
-        Err(e) => CastCheckResult::Err(e),
-    }
-}
-
 impl<'a, 'tcx> CastCheck<'tcx> {
-    fn new(
+    pub fn new(
         fcx: &FnCtxt<'a, 'tcx>,
         expr: &'tcx hir::Expr<'tcx>,
         expr_ty: Ty<'tcx>,

compiler/rustc_hir_analysis/src/check/expr.rs

@@ -3,7 +3,7 @@
 //! See `mod.rs` for more context on type checking in general.
 
 use crate::astconv::AstConv as _;
-use crate::check::cast::{self, CastCheckResult};
+use crate::check::cast;
 use crate::check::coercion::CoerceMany;
 use crate::check::fatally_break_rust;
 use crate::check::method::SelfSource;
@@ -1270,9 +1270,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         } else {
             // Defer other checks until we're done type checking.
             let mut deferred_cast_checks = self.deferred_cast_checks.borrow_mut();
-            match cast::check_cast(self, e, t_expr, t_cast, t.span, expr.span) {
-                CastCheckResult::Ok => t_cast,
-                CastCheckResult::Deferred(cast_check) => {
+            match cast::CastCheck::new(self, e, t_expr, t_cast, t.span, expr.span) {
+                Ok(cast_check) => {
                     debug!(
                         "check_expr_cast: deferring cast from {:?} to {:?}: {:?}",
                         t_cast, t_expr, cast_check,
@@ -1280,7 +1279,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     deferred_cast_checks.push(cast_check);
                     t_cast
                 }
-                CastCheckResult::Err(ErrorGuaranteed { .. }) => self.tcx.ty_error(),
+                Err(_) => self.tcx.ty_error(),
             }
         }
     }