Merge pull request #60 from hughbe/core-windows

Port lib/Core to Windows/MSVC
diff --git a/lib/Core/BuildEngine.cpp b/lib/Core/BuildEngine.cpp
index 374d310..2232deb 100644
--- a/lib/Core/BuildEngine.cpp
+++ b/lib/Core/BuildEngine.cpp
@@ -972,6 +972,8 @@
     
     // Find the cycle by searching from the entry node.
     struct WorkItem {
+      WorkItem(Rule * node) { this->node = node; }
+
       Rule* node;
       unsigned predecessorIndex = 0;
     };