powerpc: Make setjmp/longjmp signature standard

commit c17eb4dca5a353a9dbbb8ad6934fe57af7165e91 upstream.

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.

Fixes: c9029ef9c957 ("powerpc: Avoid clang warnings around setjmp and longjmp")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Clement Courbet <courbet@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200330080400.124803-1-courbet@google.com
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/powerpc/include/asm/setjmp.h b/arch/powerpc/include/asm/setjmp.h
index d930f5607ef251b6af3723bd3dd95fab4d6f8f1e..6941fe202bc822b57ef115d2e51d97c8ed83e576 100644 (file)
--- a/arch/powerpc/include/asm/setjmp.h
+++ b/arch/powerpc/include/asm/setjmp.h
@@ -12,7 +12,9 @@
 
 #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/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 5607ce67d178b14c055f8918a18cae97ea19fbf8..681f966b7211d0bd8af7c750ddaf7bc527e37898 100644 (file)
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -5,9 +5,6 @@
 
 CFLAGS_ptrace.o                += -DUTS_MACHINE='"$(UTS_MACHINE)"'
 
-# Avoid clang warnings around longjmp/setjmp declarations
-CFLAGS_crash.o += -ffreestanding
-
 subdir-ccflags-$(CONFIG_PPC_WERROR) := -Werror
 
 ifeq ($(CONFIG_PPC64),y)

diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile
index a60c44b4a3e502c63b5c4e70042169f2b3246887..93974b0a5a99ef714c00774f1f8a50650b829a0d 100644 (file)
--- 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
-
 subdir-ccflags-$(CONFIG_PPC_WERROR) += -Werror
 
 GCOV_PROFILE := n