The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From c9029ef9c95765e7b63c4d9aa780674447db1ec0 Mon Sep 17 00:00:00 2001 From: Nathan Chancellor <natechancellor@xxxxxxxxx> Date: Mon, 18 Nov 2019 21:57:11 -0700 Subject: [PATCH] powerpc: Avoid clang warnings around setjmp and longjmp Commit aea447141c7e ("powerpc: Disable -Wbuiltin-requires-header when setjmp is used") disabled -Wbuiltin-requires-header because of a warning about the setjmp and longjmp declarations. r367387 in clang added another diagnostic around this, complaining that there is no jmp_buf declaration. In file included from ../arch/powerpc/xmon/xmon.c:47: ../arch/powerpc/include/asm/setjmp.h:10:13: error: declaration of built-in function 'setjmp' requires the declaration of the 'jmp_buf' type, commonly provided in the header <setjmp.h>. [-Werror,-Wincomplete-setjmp-declaration] extern long setjmp(long *); ^ ../arch/powerpc/include/asm/setjmp.h:11:13: error: declaration of built-in function 'longjmp' requires the declaration of the 'jmp_buf' type, commonly provided in the header <setjmp.h>. [-Werror,-Wincomplete-setjmp-declaration] extern void longjmp(long *, long); ^ 2 errors generated. We are not using the standard library's longjmp/setjmp implementations for obvious reasons; make this clear to clang by using -ffreestanding on these files. Cc: stable@xxxxxxxxxxxxxxx # 4.14+ Suggested-by: Segher Boessenkool <segher@xxxxxxxxxxxxxxxxxxx> Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20191119045712.39633-3-natechancellor@xxxxxxxxx diff --git a/arch/powerpc/kexec/Makefile b/arch/powerpc/kexec/Makefile index 16c1c5a19519..378f6108a414 100644 --- a/arch/powerpc/kexec/Makefile +++ b/arch/powerpc/kexec/Makefile @@ -3,8 +3,8 @@ # Makefile for the linux kernel. # -# Disable clang warning for using setjmp without setjmp.h header -CFLAGS_crash.o += $(call cc-disable-warning, builtin-requires-header) +# Avoid clang warnings around longjmp/setjmp declarations +CFLAGS_crash.o += -ffreestanding obj-y += core.o crash.o core_$(BITS).o diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile index f142570ad860..c3842dbeb1b7 100644 --- a/arch/powerpc/xmon/Makefile +++ b/arch/powerpc/xmon/Makefile @@ -1,8 +1,8 @@ # SPDX-License-Identifier: GPL-2.0 # Makefile for xmon -# Disable clang warning for using setjmp without setjmp.h header -subdir-ccflags-y := $(call cc-disable-warning, builtin-requires-header) +# Avoid clang warnings around longjmp/setjmp declarations +subdir-ccflags-y := -ffreestanding GCOV_PROFILE := n KCOV_INSTRUMENT := n