[PATCH 01/10] loader: Use long instead of int for syscall return type in i386 code.

[Chip Davis]

December 29, 2021 12:06 PM, "Jinoh Kang" <jinoh.kang.kr at gmail.com> wrote:

> diff --git a/loader/preloader.c b/loader/preloader.c
> index 585be50624f..cb20afd4d5a 100644
> --- a/loader/preloader.c
> +++ b/loader/preloader.c
> @@ -236,7 +236,7 @@ __ASM_GLOBAL_FUNC(_start,
> 
> /* wrappers for Linux system calls */
> 
> -#define SYSCALL_RET(ret) (((ret) < 0 && (ret) > -4096) ? -1 : (ret))
> +#define SYSCALL_RET(ret) (((unsigned long)(ret) > -4096UL) ? -1 : (ret))

This seems wrong. It actually happens to be correct according to the rules of 2's-complement arithmetic (-4096 == 0xFFFFF000, -1 == 0xFFFFFFFF), but that's not obvious looking at the code. I had to work that out to verify this. That doesn't sit well with me, and I suspect it won't sit well with Alexandre, either.

> 
> static inline __attribute__((noreturn)) void wld_exit( int code )
> {


Chip