build.rs: always use freebsd12 when rustc_dep_of_std is set #3723
Conversation
|
Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @JohnTitor (or someone else) some time within the next two weeks. Please see the contribution instructions for more information. Namely, in order to ensure the minimum review times lag, PR authors and assigned reviewers should ensure that the review label (
|
RalfJung
force-pushed
the
buildrs-freebsd
branch
2 times, most recently
from
8dabe1d
to
b3d5f22
Compare
build.rs
Outdated
| 15 => set_cfg("freebsd15"), | ||
| v => panic!("unsupported FreeBSD version: {}", v), |
There was a problem hiding this comment.
Some day there will be a FreeBSD 16, so let's be forwards compatible with that.
| 15 => set_cfg("freebsd15"), | |
| v => panic!("unsupported FreeBSD version: {}", v), | |
| _ => set_cfg("freebsd15"), |
There was a problem hiding this comment.
But isn't FreeBSD not-forward-compatible? It seems wrong to load the freebsd15 module on FreeBSD 16, no?
There was a problem hiding this comment.
Do you mean backwards-compatible? It is. It will always be safe to use a FreeBSD X ABI on a FreeBSD X+1 system. You may be thinking of OpenBSD, which does not provide that guarantee.
There was a problem hiding this comment.
Ah, yes I may be mixing things up. Sorry for that.
Currently, when rustc_dep_of_std is set, the freebsd version used depends on the return value of
which_freebsd():Some(12), it usesfreebsd12freebsd11That does not seem intended? It is certainly rather odd that when building on FreeBSD 13 we'd get the freebsd11 API, but when building on FreeBSD 12 we get freebsd12. This also causes some "fun" for Miri when cross-building the freebsd std on other targets:
which_freebsd()then returnsNone, so std uses different symbols than it does in the std that is shipped by rustup.I assume the intention of #3434 was to force std to use freebsd12 when rustc_dep_of_std is set (at least that's what the comments seem to say), so let's implement that.