Re: issue with `diff -D`

[Bob Proulx]

Igor wrote:
>    #ifndef __x86_64___
>    /* some comment
>    #else /* __x86_64__ */
>    /* some DIFFERENT comment
>    #endif /* __x86_64__ */
>     */
> ...
> I don't know if this is a bug or if stuff was made simple since diff is  
> not a C parser, however, reported.

As you say, stuff was made simple.  The diff program doesn't parse the
C code.  It simply creates a diff based upon the differences in the
file.  If you had used diff -u you would have seen a more normal diff
output and the differences would have shown:

  -/* some comment
  +/* some DIFFERENT comment
    */
   int somefunc();

The -D option wraps the diff in cpp ifdef constructs.  It is a textual
convenience.  But it isn't going to perfectly handle pathological
constructs.

Thanks for the report just the same!

Bob