Re: 2.6.22-rc4-mm2: kvm compile breakage with X86_CMPXCHG64=n

From: Dave Jones
Date: Mon Jun 11 2007 - 23:23:51 EST

On Tue, Jun 12, 2007 at 02:07:18AM +0200, Adrian Bunk wrote:

> I'm getting the following compile error with CONFIG_X86_CMPXCHG64=n
> (with -Werror-implicit-function-declaration - otherwise it would be a
> link error):

We really should just get that flag into mainline so that it breaks
for people before they submit patches. We run into this constantly.

Add -Werror-implicit-function-declaration
This makes builds fail sooner if something is implicitly defined instead
of having to wait half an hour for it to fail at the linking stage.

Signed-off-by: Dave Jones <davej@xxxxxxxxxx>

--- linux-2.6/Makefile~ 2007-06-04 16:46:24.000000000 -0400
+++ linux-2.6/Makefile 2007-06-04 16:46:53.000000000 -0400
@@ -313,7 +313,8 @@ LINUXINCLUDE := -Iinclude \

CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
- -fno-strict-aliasing -fno-common
+ -fno-strict-aliasing -fno-common \
+ -Werror-implicit-function-declaration

# Read KERNELRELEASE from include/config/kernel.release (if it exists)

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