Re: [PATCH 6/7] Convert file name to toolchain format when invoking $NM.

[Charles Wilson]

On 9/9/2010 11:33 AM, Peter Rosin wrote:
> Ok, I bisected the failure to e83da49a1faf9df1c7e351df9e9b175
> "[cygwin|mingw] fix dlpreopen with --disable-static"
> 
> You know, just fix the broken stuff...without        [couldn't resist]

Oh, I know.  This was *precisely* what that patch was supposed to fix,
and DID fix back in the depths of time when it was first created, and --
I thought -- continued to fix in modern libtool.  Only now, I *guess*
because of some additional intervening changes in other parts of
libtool, it no longer actually fixed it!  However, because it DID fix
the issue on cygwin -- or, rather, did not re-break it  -- AND the mingw
(re)failure was hidden behind a separate fault, I didn't realize the
patch no longer actually FIXED the problem it was intended to fix, on mingw.

So...the patch didn't break any new tests that weren't already failing
(for other reasons) on mingw -- but neither did it actually fix what it
claimed to.  At least on mingw.  <aarrggh.>

Now, it confuses me that you state that your bisection hit that commit;
I'm VERY surprised that mdemo actually worked on mingw, PRIOR to that
commit.

After all, the point of that patch was to correct the FAILURE of that
particular test!

So, somewhere between 2009-01 and e83da49a, some OTHER change to libtool
fixed (?) the mdemo test on mingw/msys.

Sigh.

I think this whole issue arose because of the delay in reviewing that
patch.  Something changed underneath it, and instead of fixing the
problem, the patch (re)broke it.  And I didn't notice because (a) stuff
continued to work on cygwin, and (b) there was another failure, in the
same test, on mingw, which hid the fact that the updated patch (re)broke
another aspect of that test.

> Maybe you knew that this patch was the cause of the regression, but
> I didn't understand that until I bisected the regression. Your comment
> a few message back:
> 
> Den 2010-09-09 00:14 skrev Charles Wilson:
>> (However, there is an unfixed bug here; apparently something has changed
>> in libtool between when this patch was created, and when it was
>> committed, such that the static lib part no longer works properly; this
>> is why on cygwin and mingw the mdemo-exec tests STILL fail.  Very
>> frustrating.  I plan to track this down in the next day or so).
> 
> came into new light. I mean, "this patch" probably refers to the
> above mentioned commit, right?

Yes, it does.

I'm no expert on git bisect; if it's not to much trouble, could you
attempt to determine when, after 2009-01, mdemo started to work on
mingw/msys?  (Actually, localizing that on cygwin might be good enough,
if you don't have msysgit installed)

P.S. In my defense, the patch in question fixed *multiple* issues with
the whole symbol extraction behavior when both static and shared libs
exist; some of which were just bad practice but wouldn't actually cause
mdemo to fail.  See the description here:
http://lists.gnu.org/archive/html/libtool-patches/2010-06/msg00163.html


--
Chuck