https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106212
--- Comment #8 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jonathan Wakely <r...@gcc.gnu.org>: https://gcc.gnu.org/g:9616deb23a17ebe81ad89ede191d7f9f752abdec commit r15-6126-g9616deb23a17ebe81ad89ede191d7f9f752abdec Author: Jonathan Wakely <jwak...@redhat.com> Date: Tue Dec 10 10:56:41 2024 +0000 libstdc++: Disable __gnu_debug::__is_singular(T*) in constexpr [PR109517] Because of PR c++/85944 we have several bugs where _GLIBCXX_DEBUG causes errors for constexpr code. Although Bug 117966 could be fixed by avoiding redundant debug checks in std::span, and Bug 106212 could be fixed by avoiding redundant debug checks in std::array, there are many more cases where similar __glibcxx_requires_valid_range checks fail to compile and removing the checks everywhere isn't desirable. This just disables the __gnu_debug::__check_singular(T*) check during constant evaluation. Attempting to dereference a null pointer will certainly fail during constant evaluation (if it doesn't fail then it's a compiler bug and not the library's problem). Disabling this check during constant evaluation shouldn't do any harm. libstdc++-v3/ChangeLog: PR libstdc++/109517 PR libstdc++/109976 * include/debug/helper_functions.h (__valid_range_aux): Treat all input iterator ranges as valid during constant evaluation.
