From 47abdbd0fec01ba89e2d55a18b3efbf0fc519cc5 Mon Sep 17 00:00:00 2001
From: klutzy <klutzytheklutzy@gmail.com>
Date: Tue, 29 Oct 2013 01:05:33 +0900
Subject: [PATCH 1/2] rustc: Check LHS expression of assignment
Fixes #7507
Fixes #7508
---
src/librustc/middle/typeck/check/mod.rs | 11 +++++++++++
src/test/compile-fail/borrowck-assign-to-constants.rs | 1 -
2 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/src/librustc/middle/typeck/check/mod.rs b/src/librustc/middle/typeck/check/mod.rs
index 50ab7825de6..7d8a6d15768 100644
--- a/src/librustc/middle/typeck/check/mod.rs
+++ b/src/librustc/middle/typeck/check/mod.rs
@@ -2366,6 +2366,11 @@ pub fn check_expr_with_unifier(fcx: @mut FnCtxt,
let result_t = fcx.expr_ty(expr);
demand::suptype(fcx, expr.span, result_t, lhs_t);
+ let tcx = fcx.tcx();
+ if !ty::expr_is_lval(tcx, fcx.ccx.method_map, lhs) {
+ tcx.sess.span_err(lhs.span, "illegal left-hand side expression");
+ }
+
// Overwrite result of check_binop...this preserves existing behavior
// but seems quite dubious with regard to user-defined methods
// and so forth. - Niko
@@ -2538,6 +2543,12 @@ pub fn check_expr_with_unifier(fcx: @mut FnCtxt,
}
ast::ExprAssign(lhs, rhs) => {
check_assignment(fcx, lhs, rhs, id);
+
+ let tcx = fcx.tcx();
+ if !ty::expr_is_lval(tcx, fcx.ccx.method_map, lhs) {
+ tcx.sess.span_err(lhs.span, "illegal left-hand side expression");
+ }
+
let lhs_ty = fcx.expr_ty(lhs);
let rhs_ty = fcx.expr_ty(rhs);
if ty::type_is_error(lhs_ty) || ty::type_is_error(rhs_ty) {
diff --git a/src/test/compile-fail/borrowck-assign-to-constants.rs b/src/test/compile-fail/borrowck-assign-to-constants.rs
index f0dc28b736d..c0fb24c83e3 100644
--- a/src/test/compile-fail/borrowck-assign-to-constants.rs
+++ b/src/test/compile-fail/borrowck-assign-to-constants.rs
@@ -12,6 +12,5 @@ static foo: int = 5;
fn main() {
// assigning to various global constants
- None = Some(3); //~ ERROR cannot assign to immutable static item
foo = 6; //~ ERROR cannot assign to immutable static item
}
From cab00457fefb89444cd4b7a4e601dc6d200e0c86 Mon Sep 17 00:00:00 2001
From: klutzy <klutzytheklutzy@gmail.com>
Date: Tue, 29 Oct 2013 01:27:12 +0900
Subject: [PATCH 2/2] test: Add test for LHS expression check
---
src/test/compile-fail/bad-expr-lhs.rs | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
create mode 100644 src/test/compile-fail/bad-expr-lhs.rs
diff --git a/src/test/compile-fail/bad-expr-lhs.rs b/src/test/compile-fail/bad-expr-lhs.rs
new file mode 100644
index 00000000000..6907bf4b5b8
--- /dev/null
+++ b/src/test/compile-fail/bad-expr-lhs.rs
@@ -0,0 +1,20 @@
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+fn main() {
+ 1 = 2; //~ ERROR illegal left-hand side expression
+ 1 += 2; //~ ERROR illegal left-hand side expression
+ (1, 2) = (3, 4); //~ ERROR illegal left-hand side expression
+
+ let (a, b) = (1, 2);
+ (a, b) = (3, 4); //~ ERROR illegal left-hand side expression
+
+ None = Some(3); //~ ERROR illegal left-hand side expression
+}