1 files changed, 8 insertions, 0 deletions
diff --git a/compiler/rustc_mir_transform/src/validate.rs b/compiler/rustc_mir_transform/src/validate.rs
index 414477d9004..42154bbf7f2 100644
--- a/compiler/rustc_mir_transform/src/validate.rs
+++ b/compiler/rustc_mir_transform/src/validate.rs
@@ -1018,6 +1018,14 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
                 }
             }
             Rvalue::Ref(..) => {}
+            Rvalue::Len(p) => {
+                let pty = p.ty(&self.body.local_decls, self.tcx).ty;
+                check_kinds!(
+                    pty,
+                    "Cannot compute length of non-array type {:?}",
+                    ty::Array(..) | ty::Slice(..)
+                );
+            }
             Rvalue::BinaryOp(op, vals) => {
                 use BinOp::*;
                 let a = vals.0.ty(&self.body.local_decls, self.tcx);