Re: fixinc regression for <math.h> with C++ on Solaris 9

[Nathanael Nerode <neroden at twcny dot rr dot com>]

Gerald Pfeifer wrote:
> On Mon, 19 Jan 2004, Bruce Korb wrote:
>
> > I don't have CVS access here.  It might be interesting to do a ``cvs log''
> > on gcc/fixinc/tests/base/math.h and see what happened to the same code.
>
>
> It seems the code is still there. The only relevant changes I found were
> the following, which seems harmless,
>
>   date: 2003/01/04 21:14:54;  author: korbb;  state: Exp;  lines: +6 -6
>   branches:  1.11.4;
>   When wrapping files, guard with both the fix name and the file name
>
> and
>
>   revision 1.13
>   date: 2003/08/01 22:48:24;  author: neroden;  state: Exp;  lines: +1 -0
>         * fixinc/inclhack.def (broken_cabs): Make matching more generous.
>         * fixinc/fixincl.x: Regenerate.
>         * fixinc/tests/base/math.h: Regenerate to match test_text change.
>
> which lead me to the following:
>
>   revision 1.160
>   date: 2003/07/09 21:00:01;  author: neroden;  state: Exp;  lines: +3 -2
>         * fixinc/inclhack.def (math_exception):  Improve bypass and comment.
>         * fixinc/fixincl.x: Rebuild.
>
> Index: inclhack.def
> ===================================================================
> RCS file: /cvs/gcc/gcc/gcc/fixinc/inclhack.def,v
> retrieving revision 1.159
> retrieving revision 1.160
> diff -u -3 -p -r1.159 -r1.160
> --- inclhack.def        8 Jul 2003 20:42:19 -0000       1.159
> +++ inclhack.def        9 Jul 2003 21:00:01 -0000       1.160
> @@ -1680,7 +1680,8 @@ fix = {
>
>
>  /*
> - *  Some math.h files define struct exception, which conflicts with
> + *  Some math.h files define struct exception (it's in the System V
> + *  Interface Definition), which conflicts with
>   *  the class exception defined in the C++ file std/stdexcept.h.  We
>   *  redefine it to __math_exception.  This is not a great fix, but I
>   *  haven't been able to think of anything better.
> @@ -1692,7 +1693,7 @@ fix = {
>      hackname  = math_exception;
>      files     = math.h;
>      select    = "struct exception";
> -    bypass    = 'We have a problem when using C\+\+';
> +    bypass    = '__cplusplus';
>      c_fix     = wrap;
>
>      c_fix_arg = "#ifdef __cplusplus\n"
>
>
> > If it is still there, then either the fix does not trigger on the real
> > header but does on the test,
This seems likely, actually -- I made the bypass more generous so that 
it will be bypassed on more systems.  It's quite possible that the 
Solaris header claims to be c++-aware but doesn't do it correctly; I 
seem to remember something to that effect elsewhere.

* What was the original failure when using math.h with C++ on Solaris 9?
* Is Solaris 9's math.h properly guarded with #ifdef __cplusplus?
* Does it contain the text "__cplusplus"?
If it contains the text and isn't properly guarded, we have a winner.  :-(

 or else someone committed an inclhack
> > change without running the fixinc ``make check'' on the result.
>
>
> > From my results above, it seems that Nathanel indeed only ran the
> test weeks after making the patch.  fixinc is black magic to me, but
> might that be the culprit?
>
>
> > Just from inspection, there are *two* patches related to exceptions:
> >
> >  sunos_matherr_decl and math_exception
> >
> > but I do not see how they could interact on the header in question.
> > They should be re-ordered, though.  It looks like the second fix would
> > put a ``struct exception;'' in before the ``#ifdef __cplusplus'' thing.
> > (The bypass clause should prevent the application of the fix on the
> > header in question:
>
>
> Hmm, that one's definitely a bit too steep for me. :-)
>
> If there's any patch you'd like me to test, or any (header) file you'd
> like me to send, I'll happily do that, though.
>
> Gerald