patch: tree-walk.h: Warning fix

Code that is using libgit.a, and hence including GIT's headers, may get this warning:

""" ../tree-walk.h: In function 'tree_entry_len': ../tree-walk.h:25: warning: cast discards qualifiers from pointer target type ../tree-walk.h:25: warning: cast discards qualifiers from pointer target type """

This happens because the cast used in tree_entry_len() is discarding the const qualifier (thanks to Shawn Pearce by noticing this).

Signed-off-by: Luiz Fernando N. Capitulino <lcapitulino@gmail.com>

"Luiz Fernando N. Capitulino" <lcapitulino@mandriva.com.br> writes:

Grumble. Incoming "name" is already (const char*), isn't it? I'd cast only the sha1 side and apply.

However, I think -Wcast-qual is a pretty useless option.  

The nastiest one, if you care, is exec_cmd.c::execv_git_cmd() where we never muck with "const char **argv" ourselves, but we have to call execve(), which takes (char**) as its second parameter. We cast away constness for that call; otherwise you would then get prototype mismatch.

Em Fri, 22 Jun 2007 23:19:55 -0700 Junio C Hamano <gitster@pobox.com> escreveu:

| "Luiz Fernando N. Capitulino" <lcapitulino@mandriva.com.br>
| writes:
| 
| > diff --git a/tree-walk.h b/tree-walk.h
| > index ee747ab..625198f 100644
| > --- a/tree-walk.h
| > +++ b/tree-walk.h
| > @@ -22,7 +22,7 @@ static inline const unsigned char *tree_entry_extract(struct tree_desc *desc, co
| >  
| >  static inline int tree_entry_len(const char *name, const unsigned char *sha1)
| >  {
| > -	return (char *)sha1 - (char *)name - 1;
| > +	return (const char *)sha1 - (const char *)name - 1;
| >  }
| >  
| >  void update_tree_entry(struct tree_desc *);
| 
| Grumble.  Incoming "name" is already (const char*), isn't it?
| I'd cast only the sha1 side and apply.

 Yes, you're right. I'll fix it and apply again.

 Thanks a lot for the feedback.