Re: strange test failures

[Martin Sebor <msebor at gmail dot com>]

On 12/10/2016 11:03 AM, Martin Sebor wrote:
> On 12/10/2016 06:52 AM, Prathamesh Kulkarni wrote:
> > On 9 December 2016 at 05:17, Martin Sebor <msebor@gmail.com> wrote:
> > > I'm seeing failures in a few C tests that I'm not sure what to make
> > > out of.  The tests fail due to undefined symbols while linking even
> > > though they're not meant to link.  Among these are a number (but not
> > > all) of the gcc.dg/divmod-[1-6]{-simode}.c tests.
> > >
> > >   FAIL: gcc.dg/divmod-1.c (test for excess errors)
> > >
> > > The log shows that they are being built without the -S option:
> > Oops, I somehow missed adding dg-do compile to the divmod test-cases.
> > Sorry about that. The attached patch explicitly adds dg-do compile to
> > the test-cases.
> > I wonder though how I didn't see these failures. Is compile the default ?
> > Anyway I suppose explicitly marking the tests to be compile-only is
> > better.
> > Is the attached patch OK to commit ?
>
> Thanks Prathamesh!  I confess I don't know what the default is.
> But these tests pass in my other builds, either with other patches
> of mine or in a clean pull of the top of trunk. There are others
> besides the divmod where I see the same problem, including at least
> these:
>
>   pr38338.c
>   ipa/inlinehint-1.c
>   gcc.dg/params/blocksort-part.c
>   tree-ssa/ipa-split-3.c
>   Woverlength-strings-pedantic-c89.c
>   torture/pr32897.c
>
> There tend to be different sets in different builds.  Those above
> are also missing dg-do compile.  So something else must be going
> on here to cause these failures only under certain conditions.

I've narrowed the problem down to a bug in a torture/execute test
added in my patch.  It's caused by an invalid dg-warn directive:

/* { dg-warn "..." "int32plus" { target { int32plus } } */

It's "dg-warn" rather than "dg-warning" and it's missing the final
closing curly brace.

With this fixed all the other strange failures clear up.  So your
patch isn't necessary.  I guess since I run make check with a large
-jN to parallelize the tests a DejaGnu error in one of the tests
can cause cascading failures in tests run later on.

Martin

> > PS: In ChangeLog, is it acceptable to use regex ?
> > for eg:
> > testsuite/
> >     * gcc.dg/divmod-*.c: Add dg-do compile.
> > instead of listing each divmod test-case explicitly.
>
> The GNU ChangeLog style guide recommends against it:
> https://www.gnu.org/prep/standards/html_node/Style-of-Change-Logs.html
>
> Martin
>
> > Thanks,
> > Prathamesh
> > > spawn -ignore SIGHUP /opt/notnfs/msebor/build/gcc-78622/gcc/xgcc
> > > -B/opt/notnfs/msebor/build/gcc-78622/gcc/
> > > /opt/notnfs/msebor/src/gcc/gcc-78622/gcc/testsuite/gcc.dg/divmod-1.c
> > > -fno-diagnostics-show-caret -fdiagnostics-color=never -O2
> > > -fdump-tree-widening_mul-details -lm -o ./divmod-1.exe
> > > /lib/../lib64/crt1.o: In function `_start':
> > > (.text+0x20): undefined reference to `main'
> > > ...
> > >
> > > When I run make check-c I get these same failures in different tests.
> > >
> > > In successful builds the logs show that the tests are only assembled
> > > (i.e., compiled with -S), never linked.
> > >
> > > I can reproduce this on two different x86_64 machines but so far
> > > only with my patches to GCC (the middle end but none of these tests
> > > or the GCC .exp files).  Is it possible that somehow my changes cause
> > > this?  (The removal of the -S option.)  Am I missing something about
> > > how GCC tests are run?
> > >
> > > Thanks
> > > Martin
> > >
> > > PS I also see other strange errors like
> > >
> > > RROR: tcl error sourcing
> > > /opt/notnfs/msebor/src/gcc/gcc-78622/gcc/testsuite/gcc.c-torture/execute/execute.exp.
> > >
> > > ERROR: unmatched open brace in list
> > >
> > > ERROR: tcl error sourcing
> > > /opt/notnfs/msebor/src/gcc/gcc-78622/gcc/testsuite/gcc.c-torture/execute/ieee/ieee.exp.
> > >
> > > ERROR: torture-init: torture_without_loops is not empty as expected