[FFmpeg-devel] [RFC] make sure $TMPE is executable

[Reimar Döffinger]

On Thu, Sep 10, 2009 at 02:29:56PM +0100, M?ns Rullg?rd wrote:
> Reimar D?ffinger <Reimar.Doeffinger at gmx.de> writes:
> 
> > Hello,
> > it seems that "GNU gold (GNU Binutils 2.19.1) 1.7" has a strange bug
> 
> What's that?

The "new", supposedly much better and faster (IIRC ELF-only?) linker...
Or to put it simpler, that's what you get when you do experiments and
set in Gentoo the "gold" use flag for binutils (and no Gentoo flaming,
I knew what I was getting myself into, allowing people to shoot
themselves in the foot is not generally a bit thing, if nothing else
it helps evolution along - though mostly I was hoping that maybe then
compiling C++ programs would no longer be about 10 times slower than
plain C).

> > Or like this:
> > Index: configure
> > ===================================================================
> > --- configure   (revision 19808)
> > +++ configure   (working copy)
> > @@ -1489,6 +1489,7 @@
> >
> >  tmpfile TMPC  .c
> >  tmpfile TMPE  $EXESUF
> > +chmod +x $TMPE
> >  tmpfile TMPH  .h
> >  tmpfile TMPO  .o
> >  tmpfile TMPS  .S
> 
> I prefer this, but with the chmod done after all the tmpfile calls.
> It looks nicer that way.

So, should I apply this even if it is a hack?
Index: configure
===================================================================
--- configure   (revision 19808)
+++ configure   (working copy)
@@ -1493,6 +1493,7 @@
 tmpfile TMPO  .o
 tmpfile TMPS  .S
 tmpfile TMPSH .sh
+chmod +x $TMPE
 
 unset -f mktemp

 
> On a related note, I find myself questioning the practice of executing
> test files in the first place.  This obviously doesn't work when
> cross-compiling, and we do support that.  Is there no other way to do
> those tests that doesn't require executing files?

Uh, that is the test that checks if we are cross-compiling/compiler
sanity check... :-)
The only other check_exec IIRC is because ICC silently generates broken code
when ebp clobber is used, I can't think of a good way to check that
differently, even though I admit this might cause a slight
performance degradation when cross-compiling for x86 with gcc.