On Wed, 9 Jun 2010 10:12:54 -0700 Garrett Cooper <yaneurab...@gmail.com> wrote:
> On Jun 9, 2010, at 6:25 AM, Kostik Belousov wrote: > > > On Wed, Jun 09, 2010 at 09:13:56AM -0400, jhell wrote: > >> On 06/09/2010 04:14, Ilya Bakulin wrote: > >>> Hi hackers! > >>> > >>> While discussing my project's implementation details with my mentor, > >>> Alexander Leidinger, we've found that one of the ideas needs to be > >>> discussed with community, > >>> to find out possible use cases. > >>> That is, if it should be possible to spoof non-existing features. For > >>> example, if currently running kernel doesn't support FreeBSD 5.0 compat > >>> layer, "kern.features.compat_freebsd5" will be absent when querying > >>> features list. The question is -- are there any cases when we want > >>> "kern.features.compat_freebsd5" be present? If some feature is not in > >>> kernel, then presenting its existence to the userland is useless > >>> and may be even harmful, if, for example, some application relies on this > >>> feature. > >>> Or there are some scenarios where such cheat is useful? > >>> > >> > >> I can not think of any viable reason why one would want to "spoof" this > >> when it is not available. > > Many ports are doing wrong thing there, checking for run-time features at > > the build-time, turning on/off some functionality depending on its > > presence on the build host. > > It's present in the ports Makefiles as well as in many autoconf scripts. It's > bad because it causes problems with cross-build and other related scenarios, > where you can't assume that the host system is going to match the target > system. > I don't find one single file in the ports tree which uses kern.features. But I just checked what's in the tree, not what may be in the ports themselves, i.e., I didn't extract/configure any ports. -- Gary Jennejohn _______________________________________________ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "freebsd-hackers-unsubscr...@freebsd.org"
