wrong GCPRO in openp ()

wrong GCPRO in openp ()

[Kenichi Handa]

I've just got a bug report about wrong GCPRO in openp ().
The relevant code is this:

openp (path, str, suffixes, storeptr, predicate)
[...]
{
[...]
  string = filename = Qnil;
  GCPRO6 (str, string, filename, path, suffixes, encoded_fn);

As encoded_fn is not yet initialized here, there's a
possibility that it leads to crash in mark_object.  As a
simple fix is to initialized it to Qnil, I've just installed
such a change.

But, the variable encoded_fn is used as this:

[...]
	  else
	    {
	      const char *pfn;

	      encoded_fn = ENCODE_FILE (string);
	      pfn = SDATA (encoded_fn);
	      exists = (stat (pfn, &st) >= 0
			&& (st.st_mode & S_IFMT) != S_IFDIR);
	      if (exists)
		{
		  /* Check that we can access or open it.  */
		  if (NATNUMP (predicate))
		    fd = (access (pfn, XFASTINT (predicate)) == 0) ? 1 : -1;
		  else
		    fd = emacs_open (pfn, O_RDONLY, 0);
[...]

So, I think there's no need of GCPRO for encoded_fn.  Eli,
it seems that you are the last one who changed the code
around here.

2002-03-29  Eli Zaretskii  <eliz@is.elta.co.il>
[...]
	* lread.c (openp, Fload): Encode the file name before passing it
	to `stat', `access', and `emacs_open'.
	(openp): GCPRO the encoded file name.  Don't recompute Lisp
	strings unnecessarily.

Do you remember why you did this change?

---
Kenichi Handa
handa@m17n.org

Re: wrong GCPRO in openp ()

[Eli Zaretskii]

> From: Kenichi Handa <handa@m17n.org>
> Date: Mon, 06 Feb 2006 21:43:04 +0900
> 
> But, the variable encoded_fn is used as this:
> 
> [...]
> 	  else
> 	    {
> 	      const char *pfn;
> 
> 	      encoded_fn = ENCODE_FILE (string);
> 	      pfn = SDATA (encoded_fn);
> 	      exists = (stat (pfn, &st) >= 0
> 			&& (st.st_mode & S_IFMT) != S_IFDIR);
> 	      if (exists)
> 		{
> 		  /* Check that we can access or open it.  */
> 		  if (NATNUMP (predicate))
> 		    fd = (access (pfn, XFASTINT (predicate)) == 0) ? 1 : -1;
> 		  else
> 		    fd = emacs_open (pfn, O_RDONLY, 0);
> [...]
> 
> So, I think there's no need of GCPRO for encoded_fn.  Eli,
> it seems that you are the last one who changed the code
> around here.
> 
> 2002-03-29  Eli Zaretskii  <eliz@is.elta.co.il>
> [...]
> 	* lread.c (openp, Fload): Encode the file name before passing it
> 	to `stat', `access', and `emacs_open'.
> 	(openp): GCPRO the encoded file name.  Don't recompute Lisp
> 	strings unnecessarily.
> 
> Do you remember why you did this change?

Sorry, no.  Most probably because Richard (or someone else) asked me
to, but that's a guess.