diff options
| -rw-r--r-- | libbutl/optional.mxx | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/libbutl/optional.mxx b/libbutl/optional.mxx index 33ee3d3..4f34a78 100644 --- a/libbutl/optional.mxx +++ b/libbutl/optional.mxx @@ -30,10 +30,12 @@ // the latter we will check for the presence of the <optional> header which // only appeared in GCC 7. Also assume both are only available in C++17. // + // Note that on Mac OS it can still be <experimental/optional>. + // # if __cplusplus >= 201703L # if __has_include(<__config>) # include <__config> // _LIBCPP_VERSION -# if _LIBCPP_VERSION >= 4000 +# if _LIBCPP_VERSION >= 4000 && __has_include(<optional>) # define LIBBUTL_STD_OPTIONAL # endif # elif __has_include(<optional>) |