[Bug bootstrap/61315] wide-int.cc cannot be built by darwin system compiler

["manu at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61315

--- Comment #14 from Manuel López-Ibáñez <manu at gcc dot gnu.org> ---
(In reply to Dominique d'Humieres from comment #13)
> In my paranoid days I have the feeling that I don't exist on the gcc
> lists!-(although I am only interested by gfortran and optimization, I do
> what I can to keep the test suite as clean as possible for darwin: bug
> reports, debugging when I can, ...). Iain Sandoe may have a similar feeling
> too, even if he has a significant contribution in fixing darwin problem.

Why is that so? Do you mean your patches aren't reviewed fast enough?

There are three darwin maintainers. If you are unsatisfied with their work, I
would suggest to try to approach them in private. Perhaps they will be happy to
delegate some maintainership duties or suggest some way to improve
communication.

Patches going unreviewed is a general problem in GCC not restricted to Darwin.
Nobody has found a good solution to this problem yet.

> I also acknowledge that most of the GCC developers are quite helpful and
> that some of them consider their duty to fix their bugs even on darwin.
> However I consider that comments such that "darwin is broken by design",
> "darwin sucks", ... are unprofessional.

So ignore those comments. Even smart people say stupid things from time to
time. Many people that write in the GCC lists (or bug reports) don't even
contribute to GCC. When I started working on GCC diagnostics, many GCC devs
told me that there will never be native color diagnostics. Now we have colors
and the Apocalypse hasn't arrived. See also points 1 and 9 at
https://gcc.gnu.org/wiki/GCC_Research about negative feedback.

I think the approach of FX was exactly right: Expose your case and send a
patch. If you cannot convince someone, then convince others.

> Last thing I want to say, I have seen several bugs blamed to drawing that
> were gcc bugs and also several "unfixable on darwin" features that got fixed
> by gcc improvements.

Sure. I personally think that GCC is better off supporting Darwin than not, but
I wouldn't personally work on Darwin since I only care about Linux. It is only
logical that people using Darwin are the ones working on it. The quality of
Darwin support in GCC is only a function of the number of people working on it,
not a hidden agenda, design or philosophy. 

(The same is true for every other language or port or part of the compiler. The
only reason why Clang has better diagnostics than GCC is that there were 191
contributors to Clang last year, while I would be surprised if more than 20
people contributed to the C/C++ FEs during the same time.)
>From gcc-bugs-return-452710-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Wed May 28 11:25:53 2014
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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug other/61300] powerpc64le miscompile with K&R-style function definition at -O0
Date: Wed, 28 May 2014 11:25:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?ida300

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Alan Modra from comment #1)
> So, the "writes way past this" is writing into the parameter save area.
>
> compare_kr is assuming that it was called with a parameter save area because
> it isn't prototyped, but that is quite wrong because when compiling the
> function body we don't know how the function was called.  A call may well
> have a prototype in scope, and thus not set up a parameter save area.
>
> It's a bug in rs6000_function_parms_need_stack.  This function can't blindly
> test !prototype_p (fun).

So you can simply drop that check instead as it seems to be an optimization
only?  Thus

Index: gcc/config/rs6000/rs6000.c
==================================================================--- gcc/config/rs6000/rs6000.c  (revision 211011)
+++ gcc/config/rs6000/rs6000.c  (working copy)
@@ -10492,7 +10492,7 @@ rs6000_function_parms_need_stack (tree f
     fun = TREE_TYPE (fun);

   /* Varargs functions need the parameter save area.  */
-  if (!prototype_p (fun) || stdarg_p (fun))
+  if (stdarg_p (fun))
     return true;

   INIT_CUMULATIVE_INCOMING_ARGS (args_so_far_v, fun, NULL_RTX);

?