Index: lib/Transforms/Vectorize/VPlanVerifier.cpp
===================================================================
--- lib/Transforms/Vectorize/VPlanVerifier.cpp
+++ lib/Transforms/Vectorize/VPlanVerifier.cpp
@@ -24,10 +24,10 @@
                                         cl::Hidden,
                                         cl::desc("Verify VPlan H-CFG."));
 
+#ifndef NDEBUG
 /// Utility function that checks whether \p VPBlockVec has duplicate
 /// VPBlockBases.
-LLVM_ATTRIBUTE_USED static bool
-hasDuplicates(const SmallVectorImpl<VPBlockBase *> &VPBlockVec) {
+static bool hasDuplicates(const SmallVectorImpl<VPBlockBase *> &VPBlockVec) {
   SmallDenseSet<const VPBlockBase *, 8> VPBlockSet;
   for (const auto *Block : VPBlockVec) {
     if (VPBlockSet.count(Block))
@@ -36,6 +36,7 @@
   }
   return false;
 }
+#endif
 
 /// Helper function that verifies the CFG invariants of the VPBlockBases within
 /// \p Region. Checks in this function are generic for VPBlockBases. They are