Very weird error when compiling a very basic program: __addsf3 multiple defenitions

[itamarsch]

#![no_std]
#![no_main]
use arduino_hal::clock::MHz16;
use arduino_hal::hal::delay::Delay;
use arduino_hal::{delay_ms, i2c};
use arduino_hal::{I2c, Peripherals};
use lcd_lcm1602_i2c::Lcd;
use numtoa::NumToA;
use panic_serial;
const PHI: f64 = 1.61803398;

type LCD<'a> = Lcd<'a, I2c, Delay<MHz16>>;
const LCD_ADDRESS: u8 = 0x3f;
//
panic_serial::impl_panic_handler!(
  arduino_hal::usart::Usart<
    arduino_hal::pac::USART0,
    arduino_hal::port::Pin<arduino_hal::port::mode::Input, arduino_hal::hal::port::PD0>,
    arduino_hal::port::Pin<arduino_hal::port::mode::Output, arduino_hal::hal::port::PD1>
  >
);

fn lcd_init<'a>(i2c: &'a mut I2c, delay: &'a mut Delay<MHz16>) -> Result<LCD<'a>, i2c::Error> {
    let mut lcd = lcd_lcm1602_i2c::Lcd::new(i2c, delay)
        .address(LCD_ADDRESS)
        .rows(2) // two rows
        .init()?;

    lcd.backlight(lcd_lcm1602_i2c::Backlight::On)?;
    lcd.clear()?;
    lcd.set_cursor(0, 0)?;
    Ok(lcd)
}

#[arduino_hal::entry]
fn main() -> ! {
    let dp = Peripherals::take().unwrap();
    let pins = arduino_hal::pins!(dp);
    let serial = arduino_hal::default_serial!(dp, pins, 57600);
    let serial = share_serial_port_with_panic(serial);

    let mut i2c = arduino_hal::I2c::new(
        dp.TWI,
        pins.a4.into_pull_up_input(),
        pins.a5.into_pull_up_input(),
        50000,
    );

    let mut delay = arduino_hal::Delay::new();

    let mut lcd = lcd_init(&mut i2c, &mut delay).unwrap();

    let mut i: f64 = 1.0;
    let mut buf = [0u8; 100];

    loop {
        i = libm::round(i * PHI);
        let u32v = i as u32;
        delay_ms(10);
        lcd.clear().unwrap();
        lcd.set_cursor(0, 0).unwrap();
        lcd.write_str(u32v.numtoa_str(10, &mut buf)).unwrap();
    }
}

[stappersg]

I think:

• There should a git repository with the above main.rs PLUS Cargo.toml and such files for reproducablity
• This should be in a discussion

[Rahix]

First of all, you really should be avoiding the use of f64 on AVR microcontrollers. This will eat up tons and tons of memory because all floating point operations need to be implemented in software. If you really need floats, f32 is at least not quite as bloaty...

That said, the error still shouldn't happen. It is most likely a compiler issue of some sorts, though. Ping @Patryk27 maybe you know something?

[Patryk27]

It looks like I've accidentally forgotten to #[avr_skip] this intrinsic way back in 2023 👀

(tl;dr this function gets provided both by GCC's standard library and Rust's compiler-builtins, which creates a linking conflict)

I've created https://github.com/rust-lang/compiler-builtins/pull/601 to fix this; after it gets merged, I'll bump compiler-builtins within rustc and ping back, as always 🙂

[itamarsch]

It looks like I've accidentally forgotten to #[avr_skip] this intrinsic way back in 2023 👀

(tl;dr this function gets provided both by GCC's standard library and Rust's compiler-builtins, which creates a linking conflict)

I've created https://github.com/rust-lang/compiler-builtins/pull/601 to fix this; after it gets merged, I'll bump compiler-builtins within rustc and ping back, as always 🙂

In rustc where is the version of compiler-builtins defined? I'm not really familiar with the rustc codebase

[Patryk27]

Right here :-)

[itamarsch]

It looks like I've accidentally forgotten to #[avr_skip] this intrinsic way back in 2023 👀

(tl;dr this function gets provided both by GCC's standard library and Rust's compiler-builtins, which creates a linking conflict)

I've created https://github.com/rust-lang/compiler-builtins/pull/601 to fix this; after it gets merged, I'll bump compiler-builtins within rustc and ping back, as always 🙂

@Patryk27 Have you bumped up compiler-builtins?

[Patryk27]

I'm on it, but there are some (AVR-unrelated) crashes that I need to investigate.

[Patryk27]

Status: together with my AVR fix, bumping compiler-builtins brought some extra (non-AVR-related) f16 & f128 changes which need special handling in the compiler, so it's not as easy of a merge as usual - the current pull request is:

https://github.com/rust-lang/rust/pull/125016

[Patryk27]

Status: same as https://github.com/Rahix/avr-hal/issues/566#issuecomment-2276373883.

[Patryk27]

Okie, it should work on the newest toolchain 🙂