error: undefined symbol: __chkstk in compiling UEFI application on ARM64

[snoword]

Hi,

I'm creating a UEFI application on ARM64. My target .json file is as follows and it works well for a simple hello_world application.

{
  "llvm-target": "aarch64-pc-windows-msvc",
  "target-endian": "little",
  "target-pointer-width": "64",
  "target-c-int-width": "32",
  "os": "uefi",
  "arch": "aarch64",
  "data-layout": "e-m:e-i64:64-f80:128-n8:16:32:64-S128",
  "linker": "rust-lld",
  "linker-flavor": "lld-link",
  "pre-link-args": {
    "lld-link": [
        "/Subsystem:EFI_Application",
	"/Entry:wenqiu_entry",
	"/Machine:arm64"
    ]
  },
  "panic-strategy": "abort",
  "default-hidden-visibility": true,
  "executables": true,
  "exe-suffix": ".efi",
  "is-like-windows": true,
  "emit-debug-gdb-scripts": false,
}

However, when I create a static Once object
pub static MY_OBJECT: Once<MutexIrqSafe<MyStruct>> = Once::new();
and initialize it with
MY_OBJECT.call_once(|| {MutexIrqSafe::new( myobj ) });,
an error occurs

note: rust-lld: error: undefined symbol: __chkstk

I found this link #56913 and it says this error is caused by a large local variable. According to the corresponding commitment 0b00db, I add

"stack_probes": true,

in the target.json file, but the problem is still there. The toolchain I use is nightly-2019-01-02.

Does anyone know how to solve the problem?

[snoword]

@tirr-c

[tirr-c]

I understand stack_probes as configuration that makes compiler to use __rust_probestack from compiler-builtins for __chkstk. I'm guessing the build fails because __rust_probestack is not defined for ARM64 target.

Maybe a call to __chkstk is added since UEFI target is based on Windows target. MSVC runtime has __chkstk, so while the compiler is running for Windows that's not a problem.

[snoword]

I understand stack_probes as configuration that makes compiler to use __rust_probestack from compiler-builtins for __chkstk. I'm guessing the build fails because __rust_probestack is not defined for ARM64 target.

Maybe a call to __chkstk is added since UEFI target is based on Windows target. MSVC runtime has __chkstk, so while the compiler is running for Windows that's not a problem.

Thank you for your reply! I'll check if ARM64 support it.

[3Shain]

any update?

[songzhi]

I understand stack_probes as configuration that makes compiler to use __rust_probestack from compiler-builtins for __chkstk. I'm guessing the build fails because __rust_probestack is not defined for ARM64 target.

Maybe a call to __chkstk is added since UEFI target is based on Windows target. MSVC runtime has __chkstk, so while the compiler is running for Windows that's not a problem.

It's still not working now when I run it in Windows.

[Jamesbarford]

Triage: Cannot recreate using the following rust toolchain;

rustc 1.91.0-nightly (51ff89506 2025-09-02)
binary: rustc
commit-hash: 51ff895062ba60a7cba53f57af928c3fb7b0f2f4
commit-date: 2025-09-02
host: aarch64-unknown-linux-gnu
release: 1.91.0-nightly
LLVM version: 21.1.0

And trying to compile;

#![no_std]
#![no_main]
#[panic_handler]
fn panic_handler(_info: &core::panic::PanicInfo) -> ! {
    loop {}
}
#[export_name = "efi_main"]
fn main() {
    let b = [0; 1024];
}

with; rustc --target=aarch64-unknown-uefi -C panic=abort ./main.rs @davidtwco think we can close