From mboxrd@z Thu Jan 1 00:00:00 1970 From: Geert Uytterhoeven Subject: [PATCH] bitfield: Use __ffs64(x) to fix missing __ffsdi2() Date: Mon, 9 Oct 2017 10:40:49 +0200 Message-ID: <1507538449-22775-1-git-send-email-geert+renesas@glider.be> Return-path: Received: from andre.telenet-ops.be ([195.130.132.53]:47512 "EHLO andre.telenet-ops.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751598AbdJIIkx (ORCPT ); Mon, 9 Oct 2017 04:40:53 -0400 Sender: linux-arch-owner@vger.kernel.org List-ID: To: Jakub Kicinski , Arnd Bergmann , Andrew Morton Cc: kbuild test robot , linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven On most architectures[*], gcc turns __builtin_ffsll() into a call to __ffsdi2(), which is not provided by any architecture, leading to failures like: rcar-gen3-cpg.c:(.text+0x289): undefined reference to `__ffsdi2' To fix this, use __ffs64() instead, which is available on all architectures. [*] Known exceptions are some 64-bit architectures like amd64, arm64, ia64, powerpc64, and tilegx. Reported-by: kbuild test robot Fixes: 3e9b3112ec74f192 ("add basic register-field manipulation macros") Signed-off-by: Geert Uytterhoeven --- include/linux/bitfield.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/linux/bitfield.h b/include/linux/bitfield.h index 8b9d6fff002db113..0a827677372756fa 100644 --- a/include/linux/bitfield.h +++ b/include/linux/bitfield.h @@ -15,6 +15,7 @@ #ifndef _LINUX_BITFIELD_H #define _LINUX_BITFIELD_H +#include #include /* @@ -46,7 +47,7 @@ * reg |= FIELD_PREP(REG_FIELD_C, c); */ -#define __bf_shf(x) (__builtin_ffsll(x) - 1) +#define __bf_shf(x) __ffs64(x) #define __BF_FIELD_CHECK(_mask, _reg, _val, _pfx) \ ({ \ -- 2.7.4