From a31effc3bca2f0924752caeebfd6f61f7edf9a43 Mon Sep 17 00:00:00 2001 From: Antonio Sanchez Date: Wed, 17 Feb 2021 11:59:33 -0800 Subject: Add `invoke_result` and eliminate `result_of` warnings for C++17+. The `std::result_of` meta struct is deprecated in C++17 and removed in C++20. It was still slipping through due to a faulty definition of `EIGEN_HAS_STD_RESULT_OF`. Added a new macro `EIGEN_HAS_STD_INVOKE_RESULT` and `Eigen::internal::invoke_result` implementation with fallback for pre C++17. Replaces the `result_of` definition with one based on `std::invoke_result` for C++17 and higher. For completeness, added nullary op support for c++03. Fixes #1850. --- Eigen/src/Core/util/Macros.h | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'Eigen/src/Core/util/Macros.h') diff --git a/Eigen/src/Core/util/Macros.h b/Eigen/src/Core/util/Macros.h index 04e8e4d1e..b39c6ca43 100644 --- a/Eigen/src/Core/util/Macros.h +++ b/Eigen/src/Core/util/Macros.h @@ -660,8 +660,7 @@ // result_of was deprecated in c++17 and removed in c++ 20 #ifndef EIGEN_HAS_STD_RESULT_OF #if EIGEN_MAX_CPP_VER >= 11 && \ - ((defined(__cplusplus) && __cplusplus >= 201103L && __cplusplus < 201703L) || \ - __has_feature(cxx_lambdas)) + (defined(__cplusplus) && __cplusplus >= 201103L && __cplusplus < 201703L) #define EIGEN_HAS_STD_RESULT_OF 1 #else #define EIGEN_HAS_STD_RESULT_OF 0 @@ -679,6 +678,15 @@ #endif #endif // EIGEN_HAS_STD_HASH +#ifndef EIGEN_HAS_STD_INVOKE_RESULT +#if EIGEN_MAX_CPP_VER >= 17 && \ + (defined(__cplusplus) && __cplusplus >= 201703L) +#define EIGEN_HAS_STD_INVOKE_RESULT 1 +#else +#define EIGEN_HAS_STD_INVOKE_RESULT 0 +#endif +#endif + #ifndef EIGEN_HAS_ALIGNAS #if EIGEN_MAX_CPP_VER>=11 && EIGEN_HAS_CXX11 && \ ( __has_feature(cxx_alignas) \ -- cgit v1.2.3