From aa497d4352414aad22e792b35d0aaaa12bbc37c5 Mon Sep 17 00:00:00 2001
From: Segher Boessenkool <segher@kernel.crashing.org>
Date: Wed, 4 Sep 2019 14:11:07 +0000
Subject: [PATCH] powerpc: Add attributes for setjmp/longjmp

References: bsc#1065729
Patch-mainline: v5.4-rc1
Git-commit: aa497d4352414aad22e792b35d0aaaa12bbc37c5

The setjmp function should be declared as "returns_twice", or bad
things can happen[1]. This does not actually change generated code in
my testing.

The longjmp function should be declared as "noreturn", so that the
compiler can optimise calls to it better. This makes the generated
code a little shorter.

1: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-returns_005ftwice-function-attribute

Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c02ce4a573f3bac907e2c70957a2d1275f910013.1567605586.git.segher@kernel.crashing.org
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
 arch/powerpc/include/asm/setjmp.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/include/asm/setjmp.h b/arch/powerpc/include/asm/setjmp.h
index d995061f5f86..e9f81bb3f83b 100644
--- a/arch/powerpc/include/asm/setjmp.h
+++ b/arch/powerpc/include/asm/setjmp.h
@@ -7,7 +7,7 @@
 
 #define JMP_BUF_LEN    23
 
-extern long setjmp(long *);
-extern void longjmp(long *, long);
+extern long setjmp(long *) __attribute__((returns_twice));
+extern void longjmp(long *, long) __attribute__((noreturn));
 
 #endif /* _ASM_POWERPC_SETJMP_H */
-- 
2.26.2