diff --git a/src/rustc/driver/driver.rs b/src/rustc/driver/driver.rs
index 1abc36a075f..672a950f42b 100644
--- a/src/rustc/driver/driver.rs
+++ b/src/rustc/driver/driver.rs
@@ -49,6 +49,7 @@ fn default_configuration(sess: session, argv0: str, input: input) ->
     };
 
     ret [ // Target bindings.
+         attr::mk_word_item(os::family()),
          mk("target_os", os::sysname()),
          mk("target_family", os::family()),
          mk("target_arch", arch),
diff --git a/src/test/run-pass/cfg-family.rs b/src/test/run-pass/cfg-family.rs
new file mode 100644
index 00000000000..35eae3c604d
--- /dev/null
+++ b/src/test/run-pass/cfg-family.rs
@@ -0,0 +1,7 @@
+#[cfg(windows)]
+fn main() {
+}
+
+#[cfg(unix)]
+fn main() {
+}
\ No newline at end of file