https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109717
--- Comment #9 from Paul Smith <psmith at gnu dot org> --- > Now they're issued even when the "problem" is in a system header. Oh interesting: I have been in the habit of including all my 3rdparty library headers using -isystem to avoid worrying about warnings/errors in them. Regarding this issue I understand the rock versus hard place situation. If there's an assert or something that can help, I can suggest it to the fmt folks; they have been receptive to adding compiler-specific tricks in the past. If I can find the time I'll try to test this by editing my copy. I still find it strange that I can't reproduce this failure using the GDB 13.1 / fmt 9.1.0 libraries available on godbolt: it works fine there. It would be great if this warning could be split into "this is a definite problem" versus "this might be a problem", as some others have been, but I understand that could be complex and a lot of work.
