> Hi Kevin, > > typeof is (still) a GNU extension, which means that it cannot be > > used when building ISO C (e.g. -std=c99). It should therefore be > > avoided in uapi headers in favour of the ISO-friendly __typeof__. > IMHO UAPI are built with -std=c90 -Wall -Werror=implicit-function-declaration > (see usr/include/Makefile). > But one or the other, you're right both require __typeof__. > "If you are writing a header file that must work when included in ISO C > programs, write __typeof__ instead of typeof." > https://gcc.gnu.org/onlinedocs/gcc-12.2.0/gcc/Typeof.html > Reviewed-by: Petr Vorel <pvorel@xxxxxxx> > Tested-by: Petr Vorel <pvorel@xxxxxxx> IMHO problem was introduced when -std=c90 was added (back then the code was in include/uapi/linux/kernel.h). Fixes: d6fc9fcbaa65 ("kbuild: compile-test exported headers to ensure they are self-contained") Kind regards, Petr > Kind regards, > Petr > > Unfortunately this issue could not be detected by > > CONFIG_UAPI_HEADER_TEST=y as the __ALIGN_KERNEL() macro is not > > expanded in any uapi header. > > Reported-by: Ruben Ayrapetyan <ruben.ayrapetyan@xxxxxxx> > > Tested-by: Ruben Ayrapetyan <ruben.ayrapetyan@xxxxxxx> > > Signed-off-by: Kevin Brodsky <kevin.brodsky@xxxxxxx> > > --- > > include/uapi/linux/const.h | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/uapi/linux/const.h b/include/uapi/linux/const.h > > index af2a44c08683..a429381e7ca5 100644 > > --- a/include/uapi/linux/const.h > > +++ b/include/uapi/linux/const.h > > @@ -28,7 +28,7 @@ > > #define _BITUL(x) (_UL(1) << (x)) > > #define _BITULL(x) (_ULL(1) << (x)) > > -#define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1) > > +#define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (__typeof__(x))(a) - 1) > > #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask)) > > #define __KERNEL_DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
