Re: [PATCH v3] powerpc: Make setjmp/longjmp signature standard
From: Nick Desaulniers <hidden>
Date: 2020-03-30 16:21:03
Also in:
lkml, stable
On Mon, Mar 30, 2020 at 1:04 AM Clement Courbet [off-list ref] 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 <redacted> Reviewed-by: Nathan Chancellor <redacted> Tested-by: Nathan Chancellor <redacted> Cc: stable@vger.kernel.org # v4.14+ Fixes: c9029ef9c957 ("powerpc: Avoid clang warnings around setjmp and longjmp")
Third time's a charm (for patches that tackle this warning). Thanks for following up on this cleanup! Reviewed-by: Nick Desaulniers <redacted> Tested-by: Nick Desaulniers <redacted> The extent of my testing was compile testing with Clang.
quoted hunk ↗ jump to hunk
--- v2: Use and array type as suggested by Segher Boessenkool Add fix tags. v3: Properly place tags. --- 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.odiff --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 --2.26.0.rc2.310.g2932bb562d-goog
-- Thanks, ~Nick Desaulniers