| // 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 rustc_data_structures::sync::Once; |
| |
| pub fn update_limits(sess: &Session, krate: &ast::Crate) { |
| update_limit(krate, &sess.recursion_limit, "recursion_limit", 64); |
| update_limit(krate, &sess.type_length_limit, "type_length_limit", 1048576); |
| } |
| |
| fn update_limit(krate: &ast::Crate, limit: &Once<usize>, name: &str, default: usize) { |
| 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; |
| } |
| } |
| } |
| limit.set(default); |
| } |