These checks break programs compiled with _FORTIFY_SOURCE that allocate fd_sets on the heap. This has long been supported by Linux, all BSDs and many commercial Unix as a way to avoid FD_SETSIZE limits.
Please consider revising the checks to detect explicitly allocated fd_sets or add a preprocessor flag to disable the check.
These checks break programs compiled with _FORTIFY_SOURCE that allocate fd_sets on the heap. This has long been supported by Linux, all BSDs and many commercial Unix as a way to avoid FD_SETSIZE limits.
Please consider revising the checks to detect explicitly allocated fd_sets or add a preprocessor flag to disable the check.