1 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 // Checks that all rvalues in a crate have statically known size. check_crate
12 // is the public starting point.
14 use rustc::dep_graph::DepNode;
15 use rustc::middle::expr_use_visitor as euv;
16 use rustc::middle::mem_categorization as mc;
17 use rustc::ty::{self, TyCtxt};
18 use rustc::traits::Reveal;
21 use rustc::hir::intravisit::{Visitor, NestedVisitorMap};
25 pub fn check_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
26 let mut rvcx = RvalueContext { tcx: tcx };
27 tcx.visit_all_item_likes_in_krate(DepNode::RvalueCheck, &mut rvcx.as_deep_visitor());
30 struct RvalueContext<'a, 'tcx: 'a> {
31 tcx: TyCtxt<'a, 'tcx, 'tcx>,
34 impl<'a, 'tcx> Visitor<'tcx> for RvalueContext<'a, 'tcx> {
35 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
36 NestedVisitorMap::None
39 fn visit_nested_body(&mut self, body_id: hir::BodyId) {
40 let body = self.tcx.hir.body(body_id);
41 self.tcx.infer_ctxt(body_id, Reveal::UserFacing).enter(|infcx| {
42 let mut delegate = RvalueContextDelegate {
44 param_env: &infcx.parameter_environment
46 euv::ExprUseVisitor::new(&mut delegate, &infcx).consume_body(body);
48 self.visit_body(body);
52 struct RvalueContextDelegate<'a, 'gcx: 'a+'tcx, 'tcx: 'a> {
53 tcx: TyCtxt<'a, 'gcx, 'tcx>,
54 param_env: &'a ty::ParameterEnvironment<'gcx>,
57 impl<'a, 'gcx, 'tcx> euv::Delegate<'tcx> for RvalueContextDelegate<'a, 'gcx, 'tcx> {
62 _: euv::ConsumeMode) {
63 debug!("consume; cmt: {:?}; type: {:?}", *cmt, cmt.ty);
64 let ty = self.tcx.lift_to_global(&cmt.ty).unwrap();
65 if !ty.is_sized(self.tcx.global_tcx(), self.param_env, span) {
66 span_err!(self.tcx.sess, span, E0161,
67 "cannot move a value of type {0}: the size of {0} cannot be statically determined",
72 fn matched_pat(&mut self,
73 _matched_pat: &hir::Pat,
75 _mode: euv::MatchMode) {}
77 fn consume_pat(&mut self,
78 _consume_pat: &hir::Pat,
80 _mode: euv::ConsumeMode) {
84 _borrow_id: ast::NodeId,
87 _loan_region: &'tcx ty::Region,
89 _loan_cause: euv::LoanCause) {
92 fn decl_without_init(&mut self,
98 _assignment_id: ast::NodeId,
99 _assignment_span: Span,
100 _assignee_cmt: mc::cmt,
101 _mode: euv::MutateMode) {