https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115335
Bug ID: 115335 Summary: std::span at method is missing feature test macro __cpp_lib_span >= 202311L Product: gcc Version: 14.1.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: gcc at ebasoft dot com.pl Target Milestone: --- gcc (Gentoo 14.1.1_p20240518 p1) 14.1.1 20240516 In gcc stdlibc++ 14 there is method span<>::at added that should be visible only to standard c++26. https://en.cppreference.com/w/cpp/container/span/at But implementation is missing feature test macro __cpp_lib_span >= 202311L and this method is visible for all standards backward in c++20 and c++23. availability in backward standards makes difficult to refactor code for example from vector to span that will be still portable with older gcc like 13 when it is being done on platform with gcc libstdc++ 14 as there is no compiler error when method at is being used after refactoring vector to span.