From: Zhenzhong Duan <zhenzhong.duan@xxxxxxxxxx> commit 8c5477e8046ca139bac250386c08453da37ec1ae upstream. Kernel build warns: 'sanitize_boot_params' defined but not used [-Wunused-function] at below files: arch/x86/boot/compressed/cmdline.c arch/x86/boot/compressed/error.c arch/x86/boot/compressed/early_serial_console.c arch/x86/boot/compressed/acpi.c That's becausethey each include misc.h which includes a definition of sanitize_boot_params() via bootparam_utils.h. Remove the inclusion from misc.h and have the c file including bootparam_utils.h directly. Signed-off-by: Zhenzhong Duan <zhenzhong.duan@xxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Link: https://lkml.kernel.org/r/1563283092-1189-1-git-send-email-zhenzhong.duan@xxxxxxxxxx [nc: Fixed conflict around lack of 67b6662559f7f] Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx> --- Hi Greg and Sasha, Please consider applying this to 4.4 as it resolves a compilation error with clang on 4.4 and it has already been applied to 4.9 and newer: https://travis-ci.com/ClangBuiltLinux/continuous-integration/jobs/232287034 https://github.com/ClangBuiltLinux/linux/issues/654 Thanks to Ilie Halip for debugging this; TL;DR: clang pretends that it is GCC 4.2.1 for glibc compatibility and this trips up a definition of memcpy for GCC < 4.3. This is not an issue on mainline because GCC 4.6 is the earliest supported GCC version so that code was removed and this patch resolves it because string.h redefines memcpy to a proper version. arch/x86/boot/compressed/misc.c | 1 + arch/x86/boot/compressed/misc.h | 1 - 2 files changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index 16df89c30c20..1e5b68228aff 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -11,6 +11,7 @@ #include "misc.h" #include "../string.h" +#include <asm/bootparam_utils.h> /* WARNING!! * This code is compiled with -fPIC and it is relocated dynamically diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 4abb284a5b9c..bce182708814 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -19,7 +19,6 @@ #include <asm/page.h> #include <asm/boot.h> #include <asm/bootparam.h> -#include <asm/bootparam_utils.h> #define BOOT_BOOT_H #include "../ctype.h" -- 2.23.0