From 993d5ff1358cc1eeb20fc213096f6a2bf8be99ec Mon Sep 17 00:00:00 2001
From: VSadov <vsadov@microsoft.com>
Date: Thu, 11 Sep 2014 13:55:40 -0700
Subject: [PATCH] Fixed handling of parameterless struct constructors in
 expression tree lowering.

  (changeset 1333851)
---
 .../ExpressionLambdaRewriter.cs               |  4 ++-
 .../CodeGen/CodeGenConstructorInitTests.cs    | 25 +++++++++++++++++++
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/Src/Compilers/CSharp/Portable/Lowering/LambdaRewriter/ExpressionLambdaRewriter.cs b/Src/Compilers/CSharp/Portable/Lowering/LambdaRewriter/ExpressionLambdaRewriter.cs
index 8fe31748897..c74315514f4 100644
--- a/Src/Compilers/CSharp/Portable/Lowering/LambdaRewriter/ExpressionLambdaRewriter.cs
+++ b/Src/Compilers/CSharp/Portable/Lowering/LambdaRewriter/ExpressionLambdaRewriter.cs
@@ -821,7 +821,9 @@ private BoundExpression VisitObjectCreationExpressionInternal(BoundObjectCreatio
                 return Constant(node);
             }
 
-            if ((object)node.Constructor == null || node.Arguments.Length == 0)
+            if ((object)node.Constructor == null || 
+                (node.Arguments.Length == 0 && !node.Type.IsStructType()) || 
+                node.Constructor.IsDefaultValueTypeConstructor())
             {
                 return ExprFactory("New", Bound.Typeof(node.Type));
             }
diff --git a/Src/Compilers/CSharp/Test/Emit/CodeGen/CodeGenConstructorInitTests.cs b/Src/Compilers/CSharp/Test/Emit/CodeGen/CodeGenConstructorInitTests.cs
index c68195dd65f..473aced1095 100644
--- a/Src/Compilers/CSharp/Test/Emit/CodeGen/CodeGenConstructorInitTests.cs
+++ b/Src/Compilers/CSharp/Test/Emit/CodeGen/CodeGenConstructorInitTests.cs
@@ -810,5 +810,30 @@ static void Main()
             CompileAndVerifyExperimental(source, expectedOutput: "0");
         }
 
+
+        [Fact]
+        public void InstanceInitializerStructInExprTree()
+        {
+            var source = @"
+
+using System;
+using System.Linq.Expressions;
+
+class C
+{
+    struct S1
+    {
+        public int x = 42;
+    }
+
+    static void Main()
+    {
+        Expression<Func<S1>> testExpr = () => new S1();
+        System.Console.Write(testExpr.Compile()().x);
+    }
+}
+";
+            CompileAndVerifyExperimental(source, additionalRefs: new[] { ExpressionAssemblyRef }, expectedOutput: "42");
+        }
     }
 }
-- 
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