Re: About Debain Bug #532541

[Paolo Bonzini]

On 10/23/2010 09:49 AM, Kai YU wrote:
> Hi, recently I noticed the Debain Bug #532541(
> http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=532541). The problem
> reported still exists in grep-2.7. I debugged the program, and found it was
> introduce by the change of grep-2.5.3(
> http://git.savannah.gnu.org/cgit/grep.git/commit/?id=143f885e02eb98ab88a1f18e0aa8d069781bc813).
> The failure-inducing change is:
>
> - if (only_matching)
> +}
> +
> +static void
> +prline (char const *beg, char const *lim, int sep)
> +{
> + if (!only_matching)
> + print_line_head(beg, lim, sep);
> + else
>
> Notice that the predicate if (only_matching) is changed to if
> (!only_matching).

The patch is correct in adding the "!".  The code previously was doing

  static void prline(...)
  {
     /* do something */
     if (only_matching)
       /* do something else */
  }

now it is

  static void print_line_head(...)
  {
     /* do something */
  }

  static void prline(...)
  {
     if (!only_matching)
       print_line_head(...)
     else
       /* do something else */
  }

So the condition for "/* do something else */" hasn't changed.

Still, I agree there is a bug there and I'm looking into it.

Paolo