Hi Martin!

On 2025-06-21 13:37 +0300, Martin Storsjö wrote:
> > On 21. Jun 2025, at 12.20, Alexander Strasser via ffmpeg-devel <ffmpeg-devel@ffmpeg.org> wrote:
> > 
> > 
> > On 2025-06-21 00:03 +0200, Kacper Michajlow wrote:
> >> On Fri, 20 Jun 2025 at 22:26, Hendrik Leppkes
> >> <h.leppkes-at-gmail.com@ffmpeg.org> wrote:
> >>> 
> >>> On Fri, Jun 20, 2025 at 9:25 PM Timo Rothenpieler <timo@rothenpieler.org> wrote:
> >>>> 
> >>>> Likely this patch broke multiple fate runners in a silent way.
> >>>> On mine, configure simply never returns, and just sits there
> >>>> indefinitely, with no CPU usage or any activity whatsoever.
> >>>> 
> >>>> nevcairiel confirmed seeing the same behaviour on IRC.
> >>>> 
> >>>> The msys+clang builds from within the same environment work fine.
> >>>> 
> >>>> 
> >>>> Didn't verify completely if it's caused by this patch, but nothing else
> >>>> happened with configure since the last successful run.
> >>> 
> >>> I did some digging, and it happens when probe_cc probes link.exe
> >>> 
> >>> link.exe has an interactive help output (its paginated) - previously
> >>> piping stdout disabled the pagination automatically - but redirecting
> >>> it to devnull does not, and it gets stuck waiting for input.
> >>> Additionally, link.exe outputs the ident on stdout, so there is no
> >>> result on stderr (not super bad, as LD_IDENT is never used - yet)
> >> 
> >> Instead of redirecting to devnull, we could use the same condition as
> >> in if. We already look for specific ident line, so no need to head.
> >> _ident=$($_cc -nologo- 2>&1 | grep ^Microsoft | tr -d '\r')
> >> should work, no? I would be happy to see a better solution, though.
> > 
> > I think making sure to only use the first line that starts with
> > Microsoft is more robust; there could be (in the future) more lines
> > that start with Microsoft.
> > 
> >> btw. running cl.exe 3 times to just get its name is interesting :)
> > 
> > Yes, so that as well. Could be optimized, but is probably not so
> > relevant in total.
> > 
> > I propose the attached patch.
> > 
> > 
> >  Alexander
> > <0001-configure-Fix-a-regression-when-probing-link.exe.patch>
> 
> Thanks, this patch looks good to me, feel free to push! (And I can push it later today if nobody else does it before that.)
> 
> If you want to, one can also extend the commit message further to say more explicitly, that 45a30e03613a3c63d74a40f7ac86ce28dce14ff8 caused configure to hang in some configurations, which this fixes.

I have attached an updated version. Hope you like the commit message
better.

I can push it tomorrow or you can do earlier.


Thanks,
  Alexander