https://gitlab.com/freepascal.org/fpc/source/-/blob/f7c919c2f8cca593e8d3316702dee8ab31a2207c/rtl/inc/readme It hadn't been updated since 2001 and currently mentions not all sources in that directory, while some of the files mentioned are no longer existing there (at least `ucomplex.pp` and `objects.pp`). Moreover, there are typos: - `astrings.pp` instead of `astrings.inc`; - `lstrings.pp` listed as an include file while it's a unit; - maybe others...