Preprocessor problem on Cygwin

[Andreas Jaeger]

Alexandre Oliva <aoliva@redhat.com> writes:

> Every now and then, I try my (bad) luck on Cygwin.  This time, I fell
> prey of an apparent bug in the version of the Cygwin dll I had
> installed: it sets errno even when lstat() succeeds, which breaks
> cpp's pathname simplification code.
> 
> Even though I believe this is actually a bug in Cygwin, I thought I'd
> work around the problem, that might well be present in other OSs, with
> this simple patch in GCC.  Ok for mainline?  Ok for branch?

It's not a bug in Cygwin.  Errno is in general only defined when an
error occurs, the library might change it if no error occurs.  The
patch is therefore from a library perspective,

Andreas
-- 
 Andreas Jaeger
  SuSE Labs aj@suse.de
   private aj@arthur.inka.de
    http://www.suse.de/~aj