gcc-2.95.3 April 12 incomplete C++ thunks patch breaks Linux/ia32
H . J . Lu
Mon May 22 23:43:00 GMT 2000
On Fri, May 19, 2000 at 09:30:04AM -0700, H . J . Lu wrote:
> On Fri, May 19, 2000 at 12:00:07PM +0200, Franz Sirl wrote:
> > At 23:04 18.05.00, Martin v. Loewis wrote:
> > > > Even with this patch applied there's still a regression on
> > > > powerpc-linux-gnu if you run the C++ testsuite with -O2. Does it really
> > > > work for you on x86?
> > >
> > >I'm quite certain that the behaviour of these patches should not
> > >change under optimization; so any problems you see are likely
> > >unrelated.
> > I certainly does change behaviour for me and patchwise this relates to
> > current CVS+HJ's patch, if I use the sources before this went into CVS, all
> > is fine with -O2. So, before going on a wild bug hunt in an compiler area
> > I'm not really familiar with, I would like to know if this is a platform
> > independent bug. It would be very kind if someone could run the C++
> > testsuite with -O2 and assure me that everything is OK on x86.
> There is the difference between without -O2 and with -O2 for the
> patched 2.95 branch. As you can see, there are more C failures also.
> I didn't check gcc 2.95.2. I agree with Martin. I don't think his
> patch introduces any new optimization bugs. But it may trigger some
> existing bugs.
Martin, I agree with Franz. Something seems wrong with the thunks
patch. If you run the script enclosed here under
you will find all those failures are related to MI and virtual base
class. To me, it indicates a real problem.
for f in g++.mike/dyncast5.C \
$CC $CFLAGS $f $LDFLAGS
if [ $? = 0 ]; then
echo $f: ok
echo $f: failed
rm -f a.out
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