diff --git a/lib/Transforms/Scalar/GVN.cpp b/lib/Transforms/Scalar/GVN.cpp
index 95137793f20..1e89ef7b22d 100644
--- a/lib/Transforms/Scalar/GVN.cpp
+++ b/lib/Transforms/Scalar/GVN.cpp
@@ -952,8 +952,14 @@ bool GVN::processNonLocalLoad(LoadInst *LI,
 
   // If we had a phi translation failure, we'll have a single entry which is a
   // clobber in the current block.  Reject this early.
-  if (Deps.size() == 1 && Deps[0].second.isClobber())
+  if (Deps.size() == 1 && Deps[0].second.isClobber()) {
+    DEBUG(
+      DOUT << "GVN: non-local load ";
+      WriteAsOperand(*DOUT.stream(), LI);
+      DOUT << " is clobbered by " << *Deps[0].second.getInst();
+    );
     return false;
+  }
   
   // Filter out useless results (non-locals, etc).  Keep track of the blocks
   // where we have a value available in repl, also keep track of whether we see