diff --git a/mlir/lib/Analysis/AffineStructures.cpp b/mlir/lib/Analysis/AffineStructures.cpp
--- a/mlir/lib/Analysis/AffineStructures.cpp
+++ b/mlir/lib/Analysis/AffineStructures.cpp
@@ -628,7 +628,7 @@
   int64_t step = forOp.getStep();
   if (step != 1) {
     if (!forOp.hasConstantLowerBound())
-      forOp.emitWarning("domain conservatively approximated");
+      LLVM_DEBUG(forOp.emitWarning("domain conservatively approximated"));
     else {
       // Add constraints for the stride.
       // (iv - lb) % step = 0 can be written as: