diff options
Diffstat (limited to 'absl/base/config.h')
| -rw-r--r-- | absl/base/config.h | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/absl/base/config.h b/absl/base/config.h index 500bc8c8..3eb24abf 100644 --- a/absl/base/config.h +++ b/absl/base/config.h @@ -382,6 +382,19 @@ #endif #endif +// ABSL_HAVE_STD_VARIANT +// +// Checks whether C++17 std::optional is available. +#ifdef ABSL_HAVE_STD_VARIANT +#error "ABSL_HAVE_STD_VARIANT cannot be directly set." +#endif + +#ifdef __has_include +#if __has_include(<variant>) && __cplusplus >= 201703L +#define ABSL_HAVE_STD_VARIANT 1 +#endif +#endif + // ABSL_HAVE_STD_STRING_VIEW // // Checks whether C++17 std::string_view is available. @@ -396,17 +409,18 @@ #endif // For MSVC, `__has_include` is supported in VS 2017 15.3, which is later than -// the support for <optional>, <any>, <string_view>. So we use _MSC_VER to check -// whether we have VS 2017 RTM (when <optional>, <any>, <string_view> is -// implemented) or higher. -// Also, `__cplusplus` is not correctly set by MSVC, so we use `_MSVC_LANG` to -// check the language version. +// the support for <optional>, <any>, <string_view>, <variant>. So we use +// _MSC_VER to check whether we have VS 2017 RTM (when <optional>, <any>, +// <string_view>, <variant> is implemented) or higher. Also, `__cplusplus` is +// not correctly set by MSVC, so we use `_MSVC_LANG` to check the language +// version. // TODO(zhangxy): fix tests before enabling aliasing for `std::any`, // `std::string_view`. #if defined(_MSC_VER) && _MSC_VER >= 1910 && \ ((defined(_MSVC_LANG) && _MSVC_LANG > 201402) || __cplusplus > 201402) // #define ABSL_HAVE_STD_ANY 1 #define ABSL_HAVE_STD_OPTIONAL 1 +#define ABSL_HAVE_STD_VARIANT 1 // #define ABSL_HAVE_STD_STRING_VIEW 1 #endif |