Messages in this thread | | | Date | Tue, 28 Feb 2012 16:51:24 +0100 | From | Sam Ravnborg <> | Subject | Re: [PATCH] kernel.h: Include <linux/bug.h> to avoid build breakage with ARRAY_SIZE() |
| |
On Tue, Feb 28, 2012 at 10:41:39AM -0300, Fabio Estevam wrote: > Building imx_v6_v7_defconfig generated the following build error: > > arch/arm/mach-imx/cpu_op-mx51.c: In function 'mx51_get_cpu_op': > arch/arm/mach-imx/cpu_op-mx51.c:27: error: implicit declaration of function 'BUILD_BUG_ON_ZERO' > > commit 6f863554 (kernel.h: doesn't explicitly use bug.h, so don't include it.) > has removed asm/debug.h from linux/kernel.h. > > Quoting Russell King (http://www.spinics.net/lists/arm-kernel/msg161916.html) > > "linux/kernel.h _does_ use bug stuff - in ARRAY_SIZE(). > > ARRAY_SIZE() uses __must_be_array(), which is defined in linux/compiler-gcc.h, > which is obtained via linux/compiler.h and linux/linkage.h. > > linux/compiler-gcc.h defines __must_be_array() to be: > #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))
In which case linux/compiler-gcc.h uses bug.h - so this is where you should add the include. Not in kernel.h that just happens to use __must_be_array() We do not want to add "#include bug.h" to all header files that happens to use __must_be_array.
Sam
| |