[PATCH] linux: Change syscall return value to long int

[XingLi <lixing@loongson.cn>]

From: Xing Li <lixing@loongson.cn>

The kernel syscall return is long value.
The generic syscall interface return value
is int, which may lead to incorrect return value.

The following test is syscall with mmap executed on LoongArch,
only 32bits and sign extension value returned leading to mmap failure,
which should be with 47bits address returned.

Testcase:

 #include <sys/syscall.h>
 #include <sys/mman.h>
 #include <stdio.h>

void main()
{
        long int ret;
        ret = syscall(SYS_mmap, NULL, 0x801000, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
        printf("map address is %lx\n",ret);
}

Result:
[lixing@Sunhaiyong test]$ ./mmap
map address is fffffffff008c000
---
 sysdeps/unix/sysv/linux/syscall.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sysdeps/unix/sysv/linux/syscall.c b/sysdeps/unix/sysv/linux/syscall.c
index 7303ba7188..8cb0b66b1c 100644
--- a/sysdeps/unix/sysv/linux/syscall.c
+++ b/sysdeps/unix/sysv/linux/syscall.c
@@ -33,7 +33,7 @@ syscall (long int number, ...)
   long int a5 = va_arg (args, long int);
   va_end (args);
 
-  int r = INTERNAL_SYSCALL_NCS_CALL (number, a0, a1, a2, a3, a4, a5);
+  long int r = INTERNAL_SYSCALL_NCS_CALL (number, a0, a1, a2, a3, a4, a5);
   if (__glibc_unlikely (INTERNAL_SYSCALL_ERROR_P (r)))
     {
       __set_errno (-r);
-- 
2.31.1