Re: /lib/libc.so.7 vs. __libc_start1@FBSD_1.7 in main [so: 14] recently ?

On Sun, Apr 23, 2023 at 10:22 PM Mark Millard <marklmi@yahoo.com> wrote:

> [Warner answered my specific question separately. This is about
> something else.]
>
> On Apr 23, 2023, at 20:57, Warner Losh <imp@bsdimp.com> wrote:
>
> > On Sun, Apr 23, 2023 at 9:40 PM Simon J. Gerraty <sjg@juniper.net>
> wrote:
> >> Mark Millard <marklmi@yahoo.com> wrote:
> >> > I will not get into why, but I executed a git built for 1400082
> >> > in a 1400081 world context and got what was to me a surprise,
> >> > given that /lib/libc.so.7 is part of 13.2-RELEASE :
> >> >
> >> > ld-elf.so.1: /usr/local/bin/git: Undefined symbol
> "__libc_start1@FBSD_1.7"
> >>
> >> This is a symptom of trying to run a prog built for target on a host
> >> which is not the same.
> >>
> >> I hit this a lot recently while updating Makefile.depend files for
> >> userland.
> >>
> >> There are a number of makefiles (eg for sh, csh, awk) which need to run
> >> a tool on the host to generate something.
> >> When trying to build 14.0 on a 13.1 host each of those tools failed with
> >> the above issue until actually built for the host.
> >
> > Your path is messed up then. We always run (a copy of) the host's
> binaries
> > for these tools.
>
> For the kernel's vers.c generation, git is used but
> does not get a build of its own under buildworld or
> buildkernel as far as I know: not a bootstrap or
> staged tool.
>

Correct. The host's git is assumed to always be good and always executing
in a sane env.
And you can just remove / take git out of the path if you hit problems here.


> > If you were running the 14 binaries on 13 as part of the
> > build process, the path is messed up. I'm not surprised for dirdep
> > since it doesn't do all the staging activities that buildworld.
>
> git use is not covered by buildworld or kernel-toolchain
> staging activities as far as I know.
>
> Is git the only example of such for things used by buildworld
> or buildkernel ?
>

buildkernel is the only place I know that git is used to get the tip of git
branch for messages. I think that reproducible builds omit this.

Warner


> >> AFAIK the non-DIRDEPS_BUILD build does a separate pass through the tree
> >> to do the target build-tools to build these things.
> >
> > Yes and no... We copy the host's tools when we can, and build a matched
> set of
> > binary and libraries when the host one isn't good enough. I think it's a
> path
> > issue you are seeing...
> >
> > Also, "copy" isn't a physical copy because macos hates copied binaries
> due to security concerns.
> >
> >>
> >> The DIRDEPS_BUILD uses a pseudo MACHINE "host" to deal with such things,
> >> ideally those tools would be built in a subdirectory of sh, csh etc, so
> >> that one can choose to build only that tool if desired - sometimes you
> >> want to build the app (eg awk) for the host as well but usually not.
> >
> > Yea, buildworld deals with this by creating new binaries and installing
> them in
> > a special directory, which is somewhat similar (though we always build
> > them rather than on demand like dirdep hopes to do).
>
>
> ===
> Mark Millard
> marklmi at yahoo.com
>
>
>