[PATCH] kbuild: Remove gcc 4.1.0 quirk from init/main.c

Ingo Molnar
2009-01-02T15:22:19Z

* Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> wrote:

> On Friday 02 January 2009, Ingo Molnar wrote:
> >
> > * David Miller <davem@davemloft.net> wrote:
> >
> > > From: Linus Torvalds <torvalds@linux-foundation.org>
> > > Date: Wed, 31 Dec 2008 13:22:53 -0800 (PST)
> > >
> > > > On Wed, 31 Dec 2008, Andrew Morton wrote:
> > > > >
> > > > > Adrian claimed that it was gcc-4.1.0 and 4.1.1 only. He proposed
> > > > > banning them: http://lkml.org/lkml/2008/8/5/444
> > > >
> > > > If it really is just those releases, then yes, considering the number
> > > > of cases we apparently have, and considering how ugly it is in some
> > > > cases to move the weak function anywhere else, maybe banning those
> > > > versions is the proper thing to do.
> > > >
> > > > It probably won't hurt very many people - yeah, some people will be
> > > > forced to upgrade, but I have this memory of early 4.1 having had
> > > > other bugs anyway, so it's probably a good idea.
> > >
> > > I think this is probably the best way to handle this.
> >
> > okay - to move this matter from the discussion-space to the
> > solution-space, how about the patch below? (tested on x86 with a
> > non-affected compiler version.)
>
> ...or we can just merge Adrian's patch from June 2008 which also fixes
> the issue nicely.

didnt know about that patch, but yeah, sure.

> OTOH your patch has an advantage of addressing the problem in the more
> appropriate place (include/linux/compiler.h) and from what I see allows
> us to remove previous gcc 4.1.0 check from init/main.c?

Good spotting - find followup cleanup patch below.

Ingo

------------------->
>From d23cbaaa342e5555a919a543095d656415a55950 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Fri, 2 Jan 2009 16:16:16 +0100
Subject: [PATCH] kbuild: Remove gcc 4.1.0 quirk from init/main.c

Impact: cleanup

We now have a cleaner check for gcc 4.1.0/4.1.1 trouble in
include/linux/compiler.h, so remove the 4.1.0 quirk from
init/main.c.

Reported-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
init/main.c | 9 ---------
1 files changed, 0 insertions(+), 9 deletions(-)

diff --git a/init/main.c b/init/main.c
index 2a7ce0f..5ced153 100644
--- a/init/main.c
+++ b/init/main.c
@@ -75,15 +75,6 @@
#include <asm/smp.h>
#endif

-/*
- * This is one of the first .c files built. Error out early if we have compiler
- * trouble.
- */
-
-#if __GNUC__ == 4 && __GNUC_MINOR__ == 1 && __GNUC_PATCHLEVEL__ == 0
-#warning gcc-4.1.0 is known to miscompile the kernel. A different compiler version is recommended.
-#endif
-
static int kernel_init(void *);

extern void init_IRQ(void);