https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87872
--- Comment #3 from John Bytheway <jbytheway at gmail dot com> --- Created attachment 44955 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44955&action=edit Proposed patch Sure, here's a proposed patch. Tested in the sense that I have compiled and run a program against the changed code, but I have not run the libstdc++ test suite or similar. Should affect list::splice and forward_list::splice_after with _GLIBCXX_DEBUG set.