Declaring setjmp()/longjmp() as taking longs makes the signature non-standard, and makes clang complain. In the past, this has been worked around by adding -ffreestanding to the compile flags.
The implementation looks like it only ever propagates the value (in longjmp) or sets it to 1 (in setjmp), and we only call longjmp with integer parameters.
This allows removing -ffreestanding from the compilation flags.
Context: https://lore.kernel.org/patchwork/patch/1214060 https://lore.kernel.org/patchwork/patch/1216174
Signed-off-by: Clement Courbet courbet@google.com Reviewed-by: Nathan Chancellor natechancellor@gmail.com Tested-by: Nathan Chancellor natechancellor@gmail.com
---
v2: Use and array type as suggested by Segher Boessenkool Cc: stable@vger.kernel.org # v4.14+ Fixes: c9029ef9c957 ("powerpc: Avoid clang warnings around setjmp and longjmp") --- arch/powerpc/include/asm/setjmp.h | 6 ++++-- arch/powerpc/kexec/Makefile | 3 --- arch/powerpc/xmon/Makefile | 3 --- 3 files changed, 4 insertions(+), 8 deletions(-)
diff --git a/arch/powerpc/include/asm/setjmp.h b/arch/powerpc/include/asm/setjmp.h index e9f81bb3f83b..f798e80e4106 100644 --- a/arch/powerpc/include/asm/setjmp.h +++ b/arch/powerpc/include/asm/setjmp.h @@ -7,7 +7,9 @@
#define JMP_BUF_LEN 23
-extern long setjmp(long *) __attribute__((returns_twice)); -extern void longjmp(long *, long) __attribute__((noreturn)); +typedef long jmp_buf[JMP_BUF_LEN]; + +extern int setjmp(jmp_buf env) __attribute__((returns_twice)); +extern void longjmp(jmp_buf env, int val) __attribute__((noreturn));
#endif /* _ASM_POWERPC_SETJMP_H */ diff --git a/arch/powerpc/kexec/Makefile b/arch/powerpc/kexec/Makefile index 378f6108a414..86380c69f5ce 100644 --- a/arch/powerpc/kexec/Makefile +++ b/arch/powerpc/kexec/Makefile @@ -3,9 +3,6 @@ # Makefile for the linux kernel. #
-# Avoid clang warnings around longjmp/setjmp declarations -CFLAGS_crash.o += -ffreestanding - obj-y += core.o crash.o core_$(BITS).o
obj-$(CONFIG_PPC32) += relocate_32.o diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile index c3842dbeb1b7..6f9cccea54f3 100644 --- a/arch/powerpc/xmon/Makefile +++ b/arch/powerpc/xmon/Makefile @@ -1,9 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 # Makefile for xmon
-# Avoid clang warnings around longjmp/setjmp declarations -subdir-ccflags-y := -ffreestanding - GCOV_PROFILE := n KCOV_INSTRUMENT := n UBSAN_SANITIZE := n
On Mon, Mar 30, 2020 at 08:43:19AM +0200, Clement Courbet wrote:
Declaring setjmp()/longjmp() as taking longs makes the signature non-standard, and makes clang complain. In the past, this has been worked around by adding -ffreestanding to the compile flags.
The implementation looks like it only ever propagates the value (in longjmp) or sets it to 1 (in setjmp), and we only call longjmp with integer parameters.
This allows removing -ffreestanding from the compilation flags.
Context: https://lore.kernel.org/patchwork/patch/1214060 https://lore.kernel.org/patchwork/patch/1216174
Signed-off-by: Clement Courbet courbet@google.com Reviewed-by: Nathan Chancellor natechancellor@gmail.com Tested-by: Nathan Chancellor natechancellor@gmail.com
v2: Use and array type as suggested by Segher Boessenkool Cc: stable@vger.kernel.org # v4.14+ Fixes: c9029ef9c957 ("powerpc: Avoid clang warnings around setjmp and longjmp")
Actual diff itself looks good but these two tags need to be above your signoff to be included in the final changelog. Not sure if Michael will want a v3 with that or if it can manually be done when applying.
Cheers, Nathan
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