svn commit: r365889 - head/share/mk

[Ian Lepore]

On Fri, 2020-09-18 at 15:44 -0400, Mark Johnston wrote:
> On Fri, Sep 18, 2020 at 01:27:23PM -0600, Ian Lepore wrote:
> > On Fri, 2020-09-18 at 19:03 +0000, Mark Johnston wrote:
> > > Author: markj
> > > Date: Fri Sep 18 19:03:34 2020
> > > New Revision: 365889
> > > URL: https://svnweb.freebsd.org/changeset/base/365889
> > > 
> > > Log:
> > >   Install library symlinks atomically.
> > >   
> > >   As we do for shared library binaries, pass -S to install(1) when
> > >   installing symlinks.  Doing so helps avoid transient failures when
> > >   libraries are being reinstalled, which seems to be the root cause
> > > of
> > >   spurious libgcc_s.so link failures during CI builds.
> > >   
> > 
> > Actually, I believe this will just paper over the real problem, which
> > is the fact that we're building and installing the same library
> > multiple times during early build steps.  Nobody has yet been able to
> > explain why we do that, and I haven't been able to figure out why by
> > analyzing any differences in the generated files, but I'm not done
> > trying.
> 
> Sorry, this deserved more commentary in the commit log.
> 
> Indeed, we install libgcc_s.so multiple times during buildworld.  As far
> as I can see, it's intentional insofar as libgcc_s.so is listed in
> multiple library targets: it's in both _prereq_libs and _startup_libs in
> Makefile.inc1.  In particular, from scanning the log from a recent
> instance of the failure, libgcc_s gets built once but installed multiple
> times.
> 
> Why that's the case, or whether it's still necessary, is not clear to
> me.  But adding -S seemed like a desirable change in general, so I went
> forward with it.

Yeah, it has been listed in both prereq and startup list since it was
first added by kan@ in 2007 or so.  I wonder if he remembers why (added
to cc list)?

-- Ian