Re: Strange "UNRESOLVED" test results of GCC

[Jeff Law <law at redhat dot com>]

On 05/05/2017 09:09 AM, Martin Sebor wrote:
> On 05/05/2017 08:53 AM, Jeff Law wrote:
> > On 05/05/2017 08:03 AM, Xi Ruoyao wrote:
> > > Hi all,
> > >
> > > I'm testing GCC 7.1.0 and I've got some strange "UNRESOLVED" results.
> > > The corresponding fragment of gcc.sum:
> > >
> > > ... ...
> > > PASS: gcc.dg/tree-prof/wcoverage-mismatch.c compilation,  -g
> > > UNSUPPORTED:
> > > /home/xry111/gcc/gcc-svn-git/gcc/testsuite/gcc.dg/tree-prof/wcoverage-mismatch.c 
> > >
> > > -fauto-profile: cannot run
> > > create_gcov
> > > Running
> > > /home/xry111/gcc/gcc-svn-git/gcc/testsuite/gcc.dg/tree-ssa/tree-ssa.exp 
> > > ...
> > >
> > > PASS: gcc.dg/tree-ssa/20030530-2.c (test for excess errors)
> > > UNRESOLVED: gcc.dg/tree-prof/wcoverage-mismatch.c scan-tree-dump-times
> > > dom2 "first_gp_reg_save" 1
> > > UNRESOLVED: gcc.dg/tree-prof/wcoverage-mismatch.c scan-tree-dump-times
> > > dom2 "\\+" 1
> > > PASS: gcc.dg/tree-ssa/20030611-1.c (test for excess errors)
> > > ... ...
> > >
> > > It seems that some tests in tree-prof "leaked" into tree-ssa (I don't
> > > have
> > > the tool create_gcov).  Then tree-ssa.exp can't handle them and produce
> > > "UNRESOLVED" result.
> > >
> > > Is this a known issue or a bug?
> > >
> > > I'm using --enable-checking=release and LTO bootstrapping.  Could them
> > > be guilty?
> > I think there's something broken in the auto profiling dejagnu harness.
> > Test results have been unstable ever since that code was added to the
> > tree.  I remove gcc/config/i386/gcc-auto-profile to get consistent
> > results, but we really need to figure out what's wrong with the dejagnu
> > support.
>
> Many of the profiling tests routinely fail for me in parallel
> builds due to bug 77684.  A workaround (solution) in comment
> #1 makes them pass.
Given the level of pain this causes and the inability for a mere mortal 
user to change the value, I'd suggest somehow forcing the profiling 
tests to run serially would be wise.  Not sure how best to do that, 
particularly with the auto-adjusting parallel support we have in the 
testsuite these days.

jeff