Opting out of libc on Apple Silicon about hellosilicon HOT 7 OPEN

System call numbers on macOS are not stable, so Apple would like you to go through libc. Go used to create static binaries on macOS but they would constantly break whenever an update came out, so they've starting linking against the system libraries. The only reason you should be making system calls yourself is curiosity or if you have an extremely good reason that you cannot link against libSystem ;)

from hellosilicon.

Oh, no, Mach-O totally does static binaries. In fact, here's how to make one you can run on your Intel machine:

$ clang -x assembler-with-cpp -static -nostdlib -
.intel_syntax noprefix

#include <sys/syscall.h>

#define UNIX_SYSCALL 0x2000000

.globl start
start:
	mov rax, UNIX_SYSCALL | SYS_write
	mov rdi, 1
	lea rsi, text[rip]
	lea rdx, length
	syscall
	mov rax, UNIX_SYSCALL | SYS_exit
	xor rdi, rdi
	syscall

text:
.asciz "Hello, world!\n"
.equ length, . - text
$ ./a.out
Hello, world!

from hellosilicon.

Oh, no, Mach-O totally does static binaries. In fact, here's how to make one you can run on your Intel machine:

…

While you can create static binaries, the macOS kernel (XNU) allows the execution of static binaries on x86_64 only (or with debug kernels, which probably nobody outside Apple is using). On all other platforms (ARM64), the kernel enforces that an executable must use the dynamic linker (this was already linked to in the issue above). It's a restriction that cannot be bypassed. However, you can create a dynamically linked executable and simply not link to any library/framework.

from hellosilicon.

I lied, that code is likely outdated/not complete. I know of at least one statically linked binary running.

from hellosilicon.

That's cool to know! Although now that I have solved the issue of in the makefile, I will continue to work on that!

from hellosilicon.

I lied, that code is likely outdated/not complete. I know of at least one statically linked binary running.

Most interesting, the documentation I could find is also that Mach-O doesn't do static binaries.

That said, currently I am happy as long as I can easily build and deploy assembler source from the command line, and I might come back to the issue of building a Mach-O binary later ;)

from hellosilicon.

Most interesting! Any idea why the documentation would claim such a thing?

from hellosilicon.