diff --git a/mlir/lib/Transforms/Inliner.cpp b/mlir/lib/Transforms/Inliner.cpp
--- a/mlir/lib/Transforms/Inliner.cpp
+++ b/mlir/lib/Transforms/Inliner.cpp
@@ -16,6 +16,7 @@
 #include "mlir/Transforms/Passes.h"
 
 #include "mlir/Analysis/CallGraph.h"
+#include "mlir/IR/FunctionInterfaces.h"
 #include "mlir/IR/Threading.h"
 #include "mlir/Interfaces/CallInterfaces.h"
 #include "mlir/Interfaces/SideEffectInterfaces.h"
@@ -451,8 +452,22 @@
 
   // Don't allow inlining if the target is an ancestor of the call. This
   // prevents inlining recursively.
-  if (resolvedCall.targetNode->getCallableRegion()->isAncestor(
-          resolvedCall.call->getParentRegion()))
+  Region *targetRegion = resolvedCall.targetNode->getCallableRegion();
+  if (targetRegion->isAncestor(resolvedCall.call->getParentRegion()))
+    return false;
+
+  // Don't allow inlining if the source has multiple blocks (unstructured
+  // control flow) but we cannot be sure that the target supports that.
+  bool sourceHasMultipleBlocks = targetRegion->getBlocks().size() > 1;
+  // Functions typically support multiple blocks. Furthermore, if both parent
+  // ops have the same type, it is safe to inline.
+  // TODO: This does not account for ops like scf.execute_region, into which
+  // multiple blocks could be inlined.
+  bool targetSupportsMultipleBlocks =
+      targetRegion->getParentOp()->getName() ==
+          resolvedCall.call->getParentOp()->getName() ||
+      isa<FunctionOpInterface>(resolvedCall.call->getParentOp());
+  if (sourceHasMultipleBlocks && !targetSupportsMultipleBlocks)
     return false;
 
   // Otherwise, inline.
diff --git a/mlir/test/Transforms/inlining.mlir b/mlir/test/Transforms/inlining.mlir
--- a/mlir/test/Transforms/inlining.mlir
+++ b/mlir/test/Transforms/inlining.mlir
@@ -227,6 +227,17 @@
   return
 }
 
+// CHECK-LABEL: func @func_with_block_args_location_callee3
+func.func @func_with_block_args_location_callee3(%arg0 : i32) {
+  "test.dummy_op"() ({
+    // Call cannot be inlined because "test.dummy" may not support unstructured
+    // control flow in its body.
+    // CHECK: call @func_with_block_args_location
+    call @func_with_block_args_location(%arg0) : (i32) -> ()
+  }) : () -> ()
+  return
+}
+
 // Check that we can handle argument and result attributes.
 test.conversion_func_op @handle_attr_callee_fn_multi_arg(%arg0 : i16, %arg1 : i16 {"test.handle_argument"}) -> (i16 {"test.handle_result"}, i16) {
   %0 = arith.addi %arg0, %arg1 : i16