diff --git a/src/librustc/driver/driver.rs b/src/librustc/driver/driver.rs index be0c9bb0ba356..e81df63a67e46 100644 --- a/src/librustc/driver/driver.rs +++ b/src/librustc/driver/driver.rs @@ -291,6 +291,7 @@ pub fn phase_2_configure_and_expand(sess: &Session, crate_name: crate_name.to_string(), deriving_hash_type_parameter: sess.features.borrow().default_type_params, enable_quotes: sess.features.borrow().quote, + recursion_limit: sess.recursion_limit.get(), }; let ret = syntax::ext::expand::expand_crate(&sess.parse_sess, cfg, diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs index 212cd33e16e61..a137f6e78b8b6 100644 --- a/src/libsyntax/ext/base.rs +++ b/src/libsyntax/ext/base.rs @@ -463,6 +463,7 @@ pub struct ExtCtxt<'a> { pub exported_macros: Vec>, pub syntax_env: SyntaxEnv, + pub recursion_count: uint, } impl<'a> ExtCtxt<'a> { @@ -478,6 +479,7 @@ impl<'a> ExtCtxt<'a> { trace_mac: false, exported_macros: Vec::new(), syntax_env: env, + recursion_count: 0, } } @@ -552,6 +554,13 @@ impl<'a> ExtCtxt<'a> { return v; } pub fn bt_push(&mut self, ei: ExpnInfo) { + self.recursion_count += 1; + if self.recursion_count > self.ecfg.recursion_limit { + self.span_fatal(ei.call_site, + format!("Recursion limit reached while expanding the macro `{}`", + ei.callee.name).as_slice()); + } + let mut call_site = ei.call_site; call_site.expn_id = self.backtrace; self.backtrace = self.codemap().record_expansion(ExpnInfo { @@ -563,6 +572,7 @@ impl<'a> ExtCtxt<'a> { match self.backtrace { NO_EXPANSION => self.bug("tried to pop without a push"), expn_id => { + self.recursion_count -= 1; self.backtrace = self.codemap().with_expn_info(expn_id, |expn_info| { expn_info.map_or(NO_EXPANSION, |ei| ei.call_site.expn_id) }); diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs index fa3ccc8cf326e..efe4b76354f56 100644 --- a/src/libsyntax/ext/expand.rs +++ b/src/libsyntax/ext/expand.rs @@ -1069,6 +1069,7 @@ pub struct ExpansionConfig { pub crate_name: String, pub deriving_hash_type_parameter: bool, pub enable_quotes: bool, + pub recursion_limit: uint, } impl ExpansionConfig { @@ -1077,6 +1078,7 @@ impl ExpansionConfig { crate_name: crate_name, deriving_hash_type_parameter: false, enable_quotes: false, + recursion_limit: 64, } } } diff --git a/src/test/compile-fail/infinite-macro-expansion.rs b/src/test/compile-fail/infinite-macro-expansion.rs new file mode 100644 index 0000000000000..3ea5671735d04 --- /dev/null +++ b/src/test/compile-fail/infinite-macro-expansion.rs @@ -0,0 +1,22 @@ +// Copyright 2014 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. + +#![feature(macro_rules)] + +macro_rules! recursive( + () => ( + recursive!() //~ ERROR Recursion limit reached while expanding the macro `recursive` + ) + ) + +fn main() { + recursive!() +} +