diff --git a/bootstrap b/bootstrap
index 03d9ef0..6964683 100755
--- a/bootstrap
+++ b/bootstrap
@@ -1168,7 +1168,7 @@
 }
 #endif
 
-#if (__cplusplus >= 201703L || defined(__INTEL_COMPILER) && defined(__cpp_if_constexpr))
+#if (__cplusplus >= 201703L || defined(__INTEL_COMPILER) && defined(__cpp_deduction_guides))
 #include <optional>
 template <typename T,
           typename std::invoke_result<decltype(&T::get), T>::type = nullptr>