Merge topic 'bootstrap-intel'

796466284b bootstrap: Fix support for Intel compiler with modern GNU system compiler

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !5057
diff --git a/bootstrap b/bootstrap
index 0134e0c..2ef0fbb 100755
--- a/bootstrap
+++ b/bootstrap
@@ -1188,7 +1188,7 @@
 }
 #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>