From: Segher Boessenkool <segher@xxxxxxxxxxxxxxxxxxx> commit aa497d4352414aad22e792b35d0aaaa12bbc37c5 upstream. 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@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/c02ce4a573f3bac907e2c70957a2d1275f910013.1567605586.git.segher@xxxxxxxxxxxxxxxxxxx Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/powerpc/include/asm/setjmp.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/arch/powerpc/include/asm/setjmp.h +++ b/arch/powerpc/include/asm/setjmp.h @@ -12,7 +12,7 @@ #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 */
