The other answers don't tell me how to compile, I'm stuck
I have a simple hello world in assembly
.global start
.align 2
start: mov X0, #1
adr X1, hello
mov X2, #13
mov X16, #4
svc 0
mov X0, #0
mov X16, #1
svc 0
hello: .ascii "Hello\n"
I compiled it using clang hello.s -nostdlib -static
File says
% file ./a.out
./a.out: Mach-O 64-bit executable arm64
obj dump shows this and perhaps UNKNOWN_ARCHITECTURE is the problem?
./a.out: file format mach-o-arm64
Disassembly of section .text:
0000000100003fd8 <start>:
100003fd8: d2800020 mov x0, #0x1 // #1
100003fdc: 100000e1 adr x1, 100003ff8 <hello>
100003fe0: d28001a2 mov x2, #0xd // #13
100003fe4: d2800090 mov x16, #0x4 // #4
100003fe8: d4000001 svc #0x0
100003fec: d2800000 mov x0, #0x0 // #0
100003ff0: d2800030 mov x16, #0x1 // #1
100003ff4: d4000001 svc #0x0
0000000100003ff8 <hello>:
100003ff8: 6c6c6548 ldnp d8, d25, [x10, #-320]
100003ffc: Address 0x0000000100003ffc is out of bounds.
Disassembly of section LC_THREAD.UNKNOWN_ARCHITECTURE.0:
0000000000000000 <LC_THREAD.UNKNOWN_ARCHITECTURE.0>:
...
100: 00003fd8 udf #16344
104: 00000001 udf #1
...
Running in zsh says "killed" with error code 137.
This is what dtruss says
% sudo dtruss ./a.out
dtrace: system integrity protection is on, some features will not be available
dtrace: failed to execute ./a.out: Bad executable (or shared library)
Where did I go wrong? I'm on a M2
The kernel on arm64 macOS does not allow static binaries. It's as simple as that, see Why does macOS kill static executables created by clang?
But you don't need your binary to be static. Just rename start to _main and compile with clang hello.s and it will work.