Re: [PATCH 6/6] perf_counter: tools: Makefile tweaks for 64-bit powerpc

From: Ingo Molnar <mingo@elte.hu>
To: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@ozlabs.org, Peter Zijlstra <a.p.zijlstra@chello.nl>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 6/6] perf_counter: tools: Makefile tweaks for 64-bit powerpc
Date: Thu, 18 Jun 2009 11:13:34 +0200	[thread overview]
Message-ID: <20090618091334.GB21191@elte.hu> (raw)
In-Reply-To: <19000.55666.866148.559620@cargo.ozlabs.ibm.com>

* Paul Mackerras <paulus@samba.org> wrote:

> This also removes the -Werror flag when building on a 64-bit powerpc
> machine.  The userspace definition of u64 is unsigned long rather
> than unsigned long long, meaning that gcc warns every time a u64
> is printed with %Lx or %llx (though that does work properly).
> In future we may use PRI64 etc. for printing 64-bit quantities,
> which would eliminate these warnings.

> +# Don't use -Werror on ppc64; we get warnings due to using
> +# %Lx formats on __u64, which is unsigned long.
> +Werror := -Werror
> +ifeq ($(uname_M),ppc64)
> +  Werror :=
> +endif

Note, i left out this bit from the commit - we need to find a better 
solution than to allow ugly warnings on PowerPC.

Could we use the kernel's u64 type directly perhaps? That would 
allow us to change all __u64 to u64 in all of tools/perf/ which is a 
nice clean-up in any case.

	Ingo