diff --git a/mlir/lib/Transforms/Utils/DialectConversion.cpp b/mlir/lib/Transforms/Utils/DialectConversion.cpp
index df255cfcf3ec..80a696ff6233 100644
--- a/mlir/lib/Transforms/Utils/DialectConversion.cpp
+++ b/mlir/lib/Transforms/Utils/DialectConversion.cpp
@@ -1700,6 +1700,7 @@ void ConversionPatternRewriterImpl::notifyBlockInserted(
       });
   assert(!wasOpReplaced(newParentOp) &&
          "attempting to insert into a region within a replaced/erased op");
+  (void)newParentOp;
 
   patternInsertedBlocks.insert(block);