diff --git a/src/librustc/middle/typeck/check/mod.rs b/src/librustc/middle/typeck/check/mod.rs index b3600158892..b0196010cb0 100644 --- a/src/librustc/middle/typeck/check/mod.rs +++ b/src/librustc/middle/typeck/check/mod.rs @@ -2373,6 +2373,11 @@ 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 @@ -2545,6 +2550,12 @@ 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/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 or the MIT license +// , 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 +} 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 }