---

yaml
---
r: 274715
b: refs/heads/stable
c: 6d2c866
h: refs/heads/master
i:
  274713: 4f5c51d
  274711: 1666a47

Author: kamalmarhubi

[refs]

@@ -29,7 +29,7 @@ refs/heads/tmp: e06d2ad9fcd5027bcaac5b08fc9aa39a49d0ecd3
 refs/tags/1.0.0-alpha.2: 4c705f6bc559886632d3871b04f58aab093bfa2f
 refs/tags/homu-tmp: c0221c8897db309a79990367476177b1230bb264
 refs/tags/1.0.0-beta: 8cbb92b53468ee2b0c2d3eeb8567005953d40828
-refs/heads/stable: 4c4bb5ff5c5d660c565d6d79f2204e23b673d39e
+refs/heads/stable: 6d2c866e22ad1999d4a16b6b7345e031ef74655c
 refs/tags/1.0.0: 55bd4f8ff2b323f317ae89e254ce87162d52a375
 refs/tags/1.1.0: bc3c16f09287e5545c1d3f76b7abd54f2eca868b
 refs/tags/1.2.0: f557861f822c34f07270347b94b5280de20a597e

branches/stable/src/librustc_driver/lib.rs

@@ -348,10 +348,24 @@ fn handle_explain(code: &str,
     }
 }
 
+fn check_cfg(sopts: &config::Options,
+             output: ErrorOutputType) {
+    fn is_meta_list(item: &ast::MetaItem) -> bool {
+        match item.node {
+            ast::MetaItem_::MetaList(..) => true,
+            _ => false,
+        }
+    }
+
+    if sopts.cfg.iter().any(|item| is_meta_list(&*item)) {
+        early_error(output, "predicates are not allowed in --cfg");
+    }
+}
+
 impl<'a> CompilerCalls<'a> for RustcDefaultCalls {
     fn early_callback(&mut self,
                       matches: &getopts::Matches,
-                      _sopts: &config::Options,
+                      sopts: &config::Options,
                       descriptions: &diagnostics::registry::Registry,
                       output: ErrorOutputType)
                       -> Compilation {
@@ -360,6 +374,7 @@ impl<'a> CompilerCalls<'a> for RustcDefaultCalls {
             return Compilation::Stop;
         }
 
+        check_cfg(sopts, output);
         Compilation::Continue
     }
 

branches/stable/src/test/compile-fail/issue-31495.rs

@@ -0,0 +1,13 @@
+// Copyright 2015 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.
+
+// compile-flags: --cfg foo(bar)
+// error-pattern: predicates are not allowed in --cfg
+fn main() {}