https://gcc.gnu.org/g:f4932c59df387a505de69a5a1015a03caa4ccf08
commit r16-2314-gf4932c59df387a505de69a5a1015a03caa4ccf08 Author: Jonathan Wakely <jwak...@redhat.com> Date: Tue Jul 15 21:29:33 2025 +0100 libstdc++: Use __promote_3 for std::hypot [PR121097] The __promoted_t alias is only defined when __cpp_fold_expressions is defined, which might not be the case for some hypothetical C++17 compilers. Change the 3-arg std::hypot to just use __gnu_cxx::__promote_3 which is always available. libstdc++-v3/ChangeLog: PR libstdc++/121097 * include/c_global/cmath (hypot): Use __promote_3 instead of __promoted. Reviewed-by: Tomasz KamiĆski <tkami...@redhat.com> Diff: --- libstdc++-v3/include/c_global/cmath | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libstdc++-v3/include/c_global/cmath b/libstdc++-v3/include/c_global/cmath index 27c21ca19eb6..65a3b8144f35 100644 --- a/libstdc++-v3/include/c_global/cmath +++ b/libstdc++-v3/include/c_global/cmath @@ -3792,10 +3792,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { return std::__hypot3<long double>(__x, __y, __z); } template<typename _Tp, typename _Up, typename _Vp> - __gnu_cxx::__promoted_t<_Tp, _Up, _Vp> + typename __gnu_cxx::__promote_3<_Tp, _Up, _Vp>::__type hypot(_Tp __x, _Up __y, _Vp __z) { - using __type = __gnu_cxx::__promoted_t<_Tp, _Up, _Vp>; + using __type = typename __gnu_cxx::__promote_3<_Tp, _Up, _Vp>::__type; return std::__hypot3<__type>(__x, __y, __z); }