From c489379fca00630badc4019318c666d5d43ed6a5 Mon Sep 17 00:00:00 2001
From: mwilliams <mwilliams@fb.com>
Date: Mon, 18 Mar 2013 10:06:19 -0700
Subject: [PATCH] Most constructors return null

So annotate the PopR to avoid generating code.
---
 hphp/compiler/analysis/emitter.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/hphp/compiler/analysis/emitter.cpp b/hphp/compiler/analysis/emitter.cpp
index 245ea70d9..67c9b51b5 100644
--- a/hphp/compiler/analysis/emitter.cpp
+++ b/hphp/compiler/analysis/emitter.cpp
@@ -3382,6 +3382,13 @@ bool EmitterVisitor::visitImpl(ConstructPtr node) {
         }
 
         e.FCall(numParams);
+        if (Option::WholeProgram) {
+          FunctionScopePtr fs = ne->getFuncScope();
+          if (fs && !fs->getReturnType()) {
+            m_evalStack.setKnownType(KindOfNull, false /* inferred */);
+            m_evalStack.setNotRef();
+          }
+        }
         e.PopR();
         return true;
       }