Re: patch to fileio.c

[Eli Zaretskii <eliz@gnu.org>]

> From: Chong Yidong <cyd@stupidchicken.com>
> Date: Thu, 13 Nov 2008 10:43:42 -0500
> 
> "Fabrice Popineau" <fabrice.popineau@free.fr> writes:
> 
> > [ I'm posting my answer here too.]
> >
> >> Thanks for the patch.  Your analysis sounds correct.
> >>
> >> However, I would like to test it first.  Do you have a recipe for
> >> demonstrating incorrect specpdl_ptr handling (e.g. a crash)?
> >
> > I compiled emacs with msvc, and it crashed all the time under the same
> > circumstance.  Visit a file, modify it outside emacs, and try to
> > re-visit it. Emacs will detect that it has been modified and will ask
> > about reloading it. The fd is closed twice because of the
> > unwind_protect.  With msvcrt.dll, the MS C library, this is a
> > crash. I'm not sure that glibc is that picky. Possibly you won't see
> > the problem. However, to make sure, and to test the patch, I added
> > printf() statements at both places where fd can be closed, to trace
> > what happened.
> 
> Does anyone else using Windows see this problem?

I don't see the crashes, but if I run Emacs under GDB and put a
breakpoint in w32.c:sys_close, I definitely see it being called twice
for the same file descriptor on which Emacs opened the file in
insert-file-contents.