namespace std { template struct atomic { int foo; int bar; }; namespace __1 { template struct atomic { int foo; int bar; }; } // namespace __1 } // namespace std int main() { std::atomic a{1, 2}; std::atomic b{3, 4}; std::__1::atomic c{5, 6}; std::__1::atomic d{7, 8}; return 0; // Set break point at this line. }