From 1088006ed9a66f7bf7f4d4768b60b8bf165c160e Mon Sep 17 00:00:00 2001
From: Patrick Walton <pcwalton@mimiga.net>
Date: Fri, 30 Nov 2012 18:32:50 -0800
Subject: [PATCH] librustc: Implement unit-like struct constants. r=brson

---
 src/librustc/middle/trans/consts.rs    |  5 +++++
 src/test/run-pass/const-unit-struct.rs | 10 ++++++++++
 2 files changed, 15 insertions(+)
 create mode 100644 src/test/run-pass/const-unit-struct.rs

diff --git a/src/librustc/middle/trans/consts.rs b/src/librustc/middle/trans/consts.rs
index e2466c1c4c65..9291c4ba3ee7 100644
--- a/src/librustc/middle/trans/consts.rs
+++ b/src/librustc/middle/trans/consts.rs
@@ -410,6 +410,11 @@ fn const_expr(cx: @crate_ctxt, e: @ast::expr) -> ValueRef {
 
                 C_named_struct(llty, ~[ lldiscrim, C_null(llstructtys[1]) ])
             }
+            Some(ast::def_class(_)) => {
+                let ety = ty::expr_ty(cx.tcx, e);
+                let llty = type_of::type_of(cx, ety);
+                C_null(llty)
+            }
             _ => {
                 cx.sess.span_bug(e.span,
                                  ~"expected a const, fn, or variant def")
diff --git a/src/test/run-pass/const-unit-struct.rs b/src/test/run-pass/const-unit-struct.rs
new file mode 100644
index 000000000000..c0a0201ed74b
--- /dev/null
+++ b/src/test/run-pass/const-unit-struct.rs
@@ -0,0 +1,10 @@
+struct Foo;
+
+const X: Foo = Foo;
+
+fn main() {
+    match X {
+        Foo => {}
+    }
+}
+