Index: mlir/include/mlir/Interfaces/CallInterfaces.h
===================================================================
--- mlir/include/mlir/Interfaces/CallInterfaces.h
+++ mlir/include/mlir/Interfaces/CallInterfaces.h
@@ -28,4 +28,12 @@
 /// Include the generated interface declarations.
 #include "mlir/Interfaces/CallInterfaces.h.inc"
 
+namespace llvm {
+
+template <typename To>
+struct CastInfo<To, mlir::CallInterfaceCallable>
+    : public CastInfo<To, mlir::CallInterfaceCallable::PointerUnion> {};
+
+} // namespace llvm
+
 #endif // MLIR_INTERFACES_CALLINTERFACES_H