Support nested `cfg_attr` attributes

diff --git a/src/libsyntax/config.rs b/src/libsyntax/config.rs
index c164e89c52f389aa81b3d8a2fb70f22fc36af013..207289de34707d81a765c8628b642f90b8934738 100644 (file)
--- a/src/libsyntax/config.rs
+++ b/src/libsyntax/config.rs
@@ -78,7 +78,7 @@ fn process_cfg_attr(&mut self, attr: ast::Attribute) -> Option<ast::Attribute> {
         };
 
         if attr::cfg_matches(self.config, &cfg, &mut self.diag) {
-            Some(respan(mi.span, ast::Attribute_ {
+            self.process_cfg_attr(respan(mi.span, ast::Attribute_ {
                 id: attr::mk_attr_id(),
                 style: attr.node.style,
                 value: mi.clone(),

diff --git a/src/test/compile-fail/nested-cfg-attrs.rs b/src/test/compile-fail/nested-cfg-attrs.rs
new file mode 100644 (file)
index 0000000..6010b1e
--- /dev/null
+++ b/src/test/compile-fail/nested-cfg-attrs.rs
@@ -0,0 +1,14 @@
+// Copyright 2016 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.
+
+#[cfg_attr(all(), cfg_attr(all(), cfg(foo)))]
+fn f() {}
+
+fn main() { f() } //~ ERROR unresolved name `f`