diff --git a/mlir/lib/Dialect/SCF/IR/SCF.cpp b/mlir/lib/Dialect/SCF/IR/SCF.cpp
--- a/mlir/lib/Dialect/SCF/IR/SCF.cpp
+++ b/mlir/lib/Dialect/SCF/IR/SCF.cpp
@@ -1475,9 +1475,14 @@
   if (regions.empty())
     return failure();
   Region *r = regions.front();
-  assert(!r->empty());
+  if (r->empty())
+    return failure();
   Block &b = r->front();
-  auto yieldOp = llvm::dyn_cast<YieldOp>(b.getTerminator());
+  if (b.empty())
+    return failure();
+  auto yieldOp = llvm::dyn_cast<YieldOp>(b.back());
+  if (!yieldOp)
+    return failure();
   TypeRange types = yieldOp.getOperandTypes();
   inferredReturnTypes.insert(inferredReturnTypes.end(), types.begin(),
                              types.end());