correctly traverse match expressions for diverging_sub_expr

clippy_lints/src/eval_order_dependence.rs

@@ -104,7 +104,7 @@ impl<'a, 'tcx> DivergenceVisitor<'a, 'tcx> {
                         self.visit_expr(guard);
                     }
                     // make sure top level arm expressions aren't linted
-                    walk_expr(self, &*arm.body);
+                    self.maybe_walk_expr(&*arm.body);
                 }
             }
             _ => walk_expr(self, e),

tests/compile-fail/diverging_sub_expression.rs

@@ -31,6 +31,10 @@ fn foobar() {
             8 => break,
             9 => diverge(),
             3 => (println!("moo"), diverge()), //~ ERROR sub-expression diverges
+            10 => match 42 {
+                99 => return,
+                _ => ((), panic!("boo")),
+            },
             _ => (println!("boo"), break), //~ ERROR sub-expression diverges
         };
     }