https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94199
--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-9 branch has been updated by Jonathan Wakely <r...@gcc.gnu.org>: https://gcc.gnu.org/g:31b204ace293b81fc51f76bf9faf459ab1cd7c50 commit r9-8381-g31b204ace293b81fc51f76bf9faf459ab1cd7c50 Author: Jonathan Wakely <jwak...@redhat.com> Date: Mon Mar 16 22:55:48 2020 +0000 libstdc++: Add default constructor to net::service_already_exists (PR 94199) The service_already_exists exception type specified in the TS doesn't have any constructors defined. Since its base class isn't default constructible, that means has no usable constructors. This may be a defect in the TS. This patch fixes it by adding a default constructor, but making it private. The make_service function is declared as a friend to be able to call that private constructor. Backport from mainline 2020-03-16 Jonathan Wakely <jwak...@redhat.com> PR libstdc++/94199 * include/experimental/executor (service_already_exists): Add default constructor. Declare make_service to be a friend. * testsuite/experimental/net/execution_context/make_service.cc: New test.