https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105915
--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Benda Xu from comment #0) > With a MWE of > > ```c++ > #include <experimental/filesystem> > > int main(){} > ``` > would produce > ``` > /usr/lib/gcc/x86_64-pc-linux-gnu/11.3.1/include/g++-v11/experimental/bits/ > fs_path.h:1209:9: error: 'begin' is missing exception specification > 'noexcept' > path::begin() const > ^ > /usr/lib/gcc/x86_64-pc-linux-gnu/11.3.1/include/g++-v11/experimental/bits/ > fs_path.h:428:14: note: previous declaration is here > iterator begin() const noexcept; > ^ > > ``` > on a Gentoo system. Only when compiling with clang, presumably.