diff --git a/include/CLI/Optional.hpp b/include/CLI/Optional.hpp
index 160f264..9e1315e 100644
--- a/include/CLI/Optional.hpp
+++ b/include/CLI/Optional.hpp
@@ -17,10 +17,8 @@
 #endif
 #if defined(CPP11_CPP14) && __has_include(<experimental/optional>)
 #include <experimental/optional>
-#ifdef __cpp_lib_experimental_optional
 #define CLI11_EXPERIMENTAL_OPTIONAL
 #endif
-#endif
 #if __has_include(<boost/optional>)
 #include <boost/optional.hpp>
 #define CLI11_BOOST_OPTIONAL
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 36acc9a..2fc47a6 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -63,3 +63,11 @@ set_property(TARGET informational PROPERTY
 file(WRITE "${PROJECT_BINARY_DIR}/CTestCustom.cmake"
     "set(CTEST_CUSTOM_PRE_TEST \"${CMAKE_BINARY_DIR}/informational\")"
     )
+
+# Add boost to test boost::optional if available
+find_package(Boost 1.35)
+if(Boost_FOUND)
+    target_link_libraries(informational PUBLIC Boost::boost)
+    target_link_libraries(OptionalTest PUBLIC Boost::boost)
+endif()
+
diff --git a/tests/informational.cpp b/tests/informational.cpp
index ef9448a..5c219ba 100644
--- a/tests/informational.cpp
+++ b/tests/informational.cpp
@@ -21,10 +21,18 @@ int main() {
 #endif
     std::cout << "\n";
 
+    std::cout << "  __has_include: ";
+#ifdef __has_include
+    std::cout << "yes\n";
+#else
+    std::cout << "no\n";
+#endif
+
 #ifdef CLI11_OPTIONAL
     std::cout << "  [Available as CLI::optional]";
 #else
-    std::cout << "  No optional library found\n";
+        std::cout
+              << "  No optional library found\n";
 #endif
 
 #ifdef CLI11_STD_OPTIONAL