diff --git a/llvm/lib/Transforms/Scalar/LoopFlatten.cpp b/llvm/lib/Transforms/Scalar/LoopFlatten.cpp
--- a/llvm/lib/Transforms/Scalar/LoopFlatten.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopFlatten.cpp
@@ -412,7 +412,7 @@
   // increment variable.
   Increment =
       dyn_cast<BinaryOperator>(InductionPHI->getIncomingValueForBlock(Latch));
-  if (Increment->hasNUsesOrMore(3)) {
+  if (!Increment || Increment->hasNUsesOrMore(3)) {
     LLVM_DEBUG(dbgs() << "Could not find valid increment\n");
     return false;
   }