1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
|
// Copyright 2012 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.
// Recursion limit.
//
// There are various parts of the compiler that must impose arbitrary limits
// on how deeply they recurse to prevent stack overflow. Users can override
// this via an attribute on the crate like `#![recursion_limit="22"]`. This pass
// just peeks and looks for that attribute.
use session::Session;
use syntax::ast;
use std::cell::Cell;
pub fn update_limits(sess: &Session, krate: &ast::Crate) {
update_limit(sess, krate, &sess.recursion_limit, "recursion_limit",
"recursion limit");
update_limit(sess, krate, &sess.type_length_limit, "type_length_limit",
"type length limit");
}
fn update_limit(sess: &Session, krate: &ast::Crate, limit: &Cell<usize>,
name: &str, description: &str) {
for attr in &krate.attrs {
if !attr.check_name(name) {
continue;
}
if let Some(s) = attr.value_str() {
if let Some(n) = s.as_str().parse().ok() {
limit.set(n);
return;
}
}
span_err!(sess, attr.span, E0296,
"malformed {} attribute, expected #![{}=\"N\"]",
description, name);
}
}
|
