Auto merge of #5261 - matthiaskrgr:qmark, r=flip1995

use question mark operator

changelog: none

Author: bors

clippy_lints/src/consts.rs

@@ -231,13 +231,7 @@ impl<'c, 'cc> ConstEvalLateContext<'c, 'cc> {
             ExprKind::Tup(ref tup) => self.multi(tup).map(Constant::Tuple),
             ExprKind::Repeat(ref value, _) => {
                 let n = match self.tables.expr_ty(e).kind {
-                    ty::Array(_, n) => {
-                        if let Some(n) = n.try_eval_usize(self.lcx.tcx, self.lcx.param_env) {
-                            n
-                        } else {
-                            return None;
-                        }
-                    },
+                    ty::Array(_, n) => n.try_eval_usize(self.lcx.tcx, self.lcx.param_env)?,
                     _ => span_bug!(e.span, "typeck error"),
                 };
                 self.expr(value).map(|v| Constant::Repeat(Box::new(v), n))