[rfc] Use substitute-path for filename portion too

[Joel Brobecker]

> 2008-02-07  Doug Evans  <dje@google.com>
> 
> 	* source.c (find_and_open_source): Always rewrite absolute filenames.

No problem from my end.

> +
> +  if (IS_ABSOLUTE_PATH (filename))
>      {
> -      /* If dirname is NULL, chances are the path is embedded in
> -         the filename.  Try the source path substitution on it.  */
> +      /* If filename is absolute path, try the source path
> +	 substitution on it.  */

Do we want to restrict this to filenames that are absolute paths?
Imagine the filename was codesourcery/bar/bar.h and the rewrite was
s/codesourcery/adacore/, do we want to attempt the rewrite then?
I suppose we should wait to see a real example of such a situation
before trying to support it...

-- 
Joel