Re: test-rwlock1 failing on latest Fedora Rawhide

[Richard W.M. Jones]

On Wed, Jan 23, 2019 at 09:01:19PM +0100, Bruno Haible wrote:
> Hi Rich,
> 
> > I cannot reproduce this locally, hence my bug report is rather devoid
> > of details.  However, it's 100% reproducible in Koji (the Fedora
> > Rawhide build system) on *all* architectures except armv7:
> > 
> > FAIL: test-rwlock1
> > ==================
> > Unexpected outcome 3
> > FAIL: test-thread_create
> 
> As written in [1]:
> "Unexpected outcome 3" means that the test program could not create a second
> thread (other than the main thread).
> 
> On glibc systems, this typically means that the 'test-rwlock1' program has not
> been linked with '-lpthread'.
> 
> > The full log is here:
> > 
> > https://kojipkgs.fedoraproject.org//work/tasks/4382/32214382/build.log
> 
> The configure command-line looks right.
> 
> I see
>   LDFLAGS='-Wl,-z,relro -Wl,--as-needed  -Wl,-z,now 
> -specs=/usr/lib/rpm/redhat/redhat-hardened-ld'
> 
> A global "-Wl,--as-needed" has the effect of removing libraries like
> -lpthread from the link. Which would explain the symptom.

Ahhhhhhh, that would also explain why I couldn't reproduce it.  I was
using the default flags when I was testing locally.  Using the Fedora
flags, I *can* reproduce it locally, thanks!

> What do the other elements of LDFLAGS do?

All the flags AFAIK come from Fedora and are needed for hardening or
other Fedora policy purposes.

I checked the history of the Fedora package which adds these flags, and
it seems like --as-needed was added for:

https://fedoraproject.org/wiki/Changes/RemoveExcessiveLinking

Removing -Wl,--as-needed fixes the problem.  However I'm still unclear
about this.  Is Fedora wrong?  Is hivex using gnulib wrongly?  Is
gnulib wrong?

Rich.

> Bruno
> 
> [1] http://lists.gnu.org/archive/html/coreutils/2018-02/msg00020.html

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