---

yaml
---
r: 211446
b: refs/heads/tmp
c: 57c75b6
h: refs/heads/master
v: v3

Author: nikomatsakis

[refs]

@@ -32,7 +32,7 @@ refs/heads/building: 126db549b038c84269a1e4fe46f051b2c15d6970
 refs/heads/beta: 2d00dc3b85aaf81caa3a4e5764c5e185a4dd0a7c
 refs/heads/windistfix: 7608dbad651f02e837ed05eef3d74a6662a6e928
 refs/tags/1.0.0-alpha: e42bd6d93a1d3433c486200587f8f9e12590a4d7
-refs/heads/tmp: 710270d9c0b9b9e65e606e1c6109329c93499837
+refs/heads/tmp: 57c75b6b10c329ed1c9c1957e98a990dd04608f2
 refs/tags/1.0.0-alpha.2: 4c705f6bc559886632d3871b04f58aab093bfa2f
 refs/tags/homu-tmp: 704c2ee730d2e948d11a2edd77e3f35de8329a6e
 refs/heads/gate: 97c84447b65164731087ea82685580cc81424412

branches/tmp/src/librustc/middle/check_const.rs

@@ -205,7 +205,16 @@ impl<'a, 'tcx> CheckCrateVisitor<'a, 'tcx> {
                             ret_ty: Ty<'tcx>)
                             -> bool {
         if let Some(fn_like) = const_eval::lookup_const_fn_by_id(self.tcx, def_id) {
-            if self.mode != Mode::Var && !self.tcx.sess.features.borrow().const_fn {
+            if
+                // we are in a static/const initializer
+                self.mode != Mode::Var &&
+
+                // feature-gate is not enabled
+                !self.tcx.sess.features.borrow().const_fn &&
+
+                // this doesn't come from a macro that has #[allow_internal_unstable]
+                !self.tcx.sess.codemap().span_allows_unstable(expr.span)
+            {
                 self.tcx.sess.span_err(
                     expr.span,
                     &format!("const fns are an unstable feature"));