---

yaml
---
r: 28132
b: refs/heads/try
c: 0031617
h: refs/heads/master
v: v3

Author: Elliott Slaughter

[refs]

@@ -2,7 +2,7 @@
 refs/heads/master: cd6f24f9d14ac90d167386a56e7a6ac1f0318195
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
 refs/heads/snap-stage3: cd6f24f9d14ac90d167386a56e7a6ac1f0318195
-refs/heads/try: adf9fa229fbf9da048c766ec966d6d7c0babb5c9
+refs/heads/try: 0031617f30f159df2cef301c9d574cd219e16b16
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b
 refs/heads/try2: d0c6ce338884ee21843f4b40bf6bf18d222ce5df

branches/try/src/rustc/driver/driver.rs

@@ -62,22 +62,29 @@ fn default_configuration(sess: session, argv0: ~str, input: input) ->
          mk(~"build_input", source_name(input))];
 }
 
+fn append_configuration(cfg: ast::crate_cfg, name: ~str) -> ast::crate_cfg {
+    if attr::contains_name(cfg, name) {
+        return cfg;
+    } else {
+        return vec::append_one(cfg, attr::mk_word_item(name));
+    }
+}
+
 fn build_configuration(sess: session, argv0: ~str, input: input) ->
    ast::crate_cfg {
     // Combine the configuration requested by the session (command line) with
     // some default and generated configuration items
     let default_cfg = default_configuration(sess, argv0, input);
     let user_cfg = sess.opts.cfg;
     // If the user wants a test runner, then add the test cfg
-    let gen_cfg =
-        {
-            if sess.opts.test && !attr::contains_name(user_cfg, ~"test") {
-                ~[attr::mk_word_item(~"test")]
-            } else {
-                ~[attr::mk_word_item(~"notest")]
-            }
-        };
-    return vec::append(vec::append(user_cfg, gen_cfg), default_cfg);
+    let user_cfg = append_configuration(
+        user_cfg,
+        if sess.opts.test { ~"test" } else { ~"notest" });
+    // If the user requested GC, then add the GC cfg
+    let user_cfg = append_configuration(
+        user_cfg,
+        if sess.opts.gc { ~"gc" } else { ~"nogc" });
+    return vec::append(user_cfg, default_cfg);
 }
 
 // Convert strings provided as --cfg [cfgspec] into a crate_cfg