Don't add struct names to the value name space if there's no constructor

Closes #3149

Author: catamorphism

src/rustc/middle/resolve3.rs

@@ -987,22 +987,30 @@ class Resolver {
                 }
             }
             item_class(struct_definition, _) => {
-              let (name_bindings, new_parent) = self.add_child(atom, parent,
-                                              ~[ValueNS, TypeNS], sp);
-
-                (*name_bindings).define_type(def_ty(local_def(item.id)), sp);
-
-                match struct_definition.ctor {
+                let (name_bindings, new_parent) =
+                    match struct_definition.ctor {
                     none => {
-                        // Nothing to do.
+                        let (name_bindings, new_parent) = self.add_child(atom,
+                              parent, ~[TypeNS], sp);
+
+                        (*name_bindings).define_type(def_ty(
+                            local_def(item.id)), sp);
+                        (name_bindings, new_parent)
                     }
                     some(ctor) => {
+                        let (name_bindings, new_parent) = self.add_child(atom,
+                                 parent, ~[ValueNS, TypeNS], sp);
+
+                        (*name_bindings).define_type(def_ty(
+                            local_def(item.id)), sp);
+
                         let purity = ctor.node.dec.purity;
                         let ctor_def = def_fn(local_def(ctor.node.id),
                                               purity);
                         (*name_bindings).define_value(ctor_def, sp);
+                        (name_bindings, new_parent)
                     }
-                }
+                };
 
                 // Create the set of implementation information that the
                 // implementation scopes (ImplScopes) need and write it into

src/test/run-pass/issue-3149.rs

@@ -0,0 +1,24 @@
+import Num = num::num;
+
+pure fn Matrix4<T:copy Num>(m11: T, m12: T, m13: T, m14: T,
+                                     m21: T, m22: T, m23: T, m24: T,
+                                     m31: T, m32: T, m33: T, m34: T,
+                                     m41: T, m42: T, m43: T, m44: T)
+                                  -> Matrix4<T> {
+
+    Matrix4 {
+        m11: m11, m12: m12, m13: m13, m14: m14,
+        m21: m21, m22: m22, m23: m23, m24: m24,
+        m31: m31, m32: m32, m33: m33, m34: m34,
+        m41: m41, m42: m42, m43: m43, m44: m44
+    }
+}
+
+struct Matrix4<T:copy Num> {
+    let m11: T; let m12: T; let m13: T; let m14: T;
+    let m21: T; let m22: T; let m23: T; let m24: T;
+    let m31: T; let m32: T; let m33: T; let m34: T;
+    let m41: T; let m42: T; let m43: T; let m44: T;
+}
+
+fn main() {}