On Tue, May 19, 2020 at 10:23:18AM -0400, Wietse Venema wrote: > Rich Felker: > > The is fundamentally no build-time test possible for this. Even if we > > were willing to make flags for each bug (or missing feature) that was > > ever fixed indicating the change, that would only tell you whether the > > version present at build time had the property, not whether the > > version present at runtime does. With a distro, unless the distro > > If you can provide a libc-musl runtime __version variable, then > Postfix can at run time determine that the library supports the > necessary functionality, and enable/disable DANE accordingly.
We've been over this countless times from folks requesting version numbers. A version number does not tell you what you want to know. Distros will patch the functionality into whatever version they're shipping. A 1.1.25 (if it ever happens) will likely have the patch backported (just applied; no conflict). Querying features has to be done on a per-feature basis not based on version numbers. See the proposal on libc-coord.
