Crash on Linux, X11, in Calculator example

[pzmarzly]

Video on YouTube - I'm clicking the multiply button, yet nothing happens.

Then, as seen in the video, it crashes:

An unexpected panic ocurred, the program has to exit.
Please report this error and attach the log file found in the directory of the executable.

The error ocurred in: examples/calculator.rs at line 108 in thread main

Error information:
attempt to subtract with overflow

Backtrace:

backtrace::backtrace::libunwind::trace @ libunwind.rs:53
backtrace::backtrace::trace @ mod.rs:42
backtrace::capture::Backtrace::new_unresolved @ capture.rs:88
backtrace::capture::Backtrace::new @ capture.rs:63
azul::logging::set_up_panic_hooks::panic_fn @ logging.rs:87
core::ops::function::Fn::call @ function.rs:73
std::panicking::rust_panic_with_hook @ panicking.rs:479
std::panicking::continue_panic_fmt @ panicking.rs:390
 @ panicking.rs:325
core::panicking::panic_fmt @ panicking.rs:77
core::panicking::panic @ panicking.rs:52
calculator::OperandStack::get_number @ calculator.rs:108
calculator::handle_mouseclick_numpad::{{closure}} @ calculator.rs:231
<alloc::sync::Arc<std::sync::mutex::Mutex<T>> as azul::traits::Modify<T>>::modify @ traits.rs:45
calculator::handle_mouseclick_numpad @ calculator.rs:229
azul::app::do_hit_test_and_call_callbacks::{{closure}} @ app.rs:770
azul::app::do_hit_test_and_call_callbacks @ app.rs:782
<azul::app::App<T>>::run_inner @ app.rs:255
<azul::app::App<T>>::run @ app.rs:209
calculator::main @ calculator.rs:260
std::rt::lang_start::{{closure}} @ rt.rs:74
std::rt::lang_start_internal::{{closure}} @ rt.rs:59
std::panicking::try::do_call @ panicking.rs:310
 @ lib.rs:105
std::panicking::try @ panicking.rs:289
std::panic::catch_unwind @ panic.rs:392
std::rt::lang_start_internal @ rt.rs:58
std::rt::lang_start @ rt.rs:74
unresolved function

[pzmarzly]

I tested it on i3wm and Cinnamon, crashed on both.

[fschutt]

Yes, it doesn't have to do anything with the graphics, it has to do with the application logic. It'll probably also crash on Windows.

https://github.com/maps4print/azul/blob/679af60d6bda4f999eb7518c870dac4d2f8c1a65/examples/calculator.rs#L108

It crashes at the "-1", because "0 - 1" underflows the bounds of a usize.

[pzmarzly]

Is the calculator supposed to be functional? If so, how should I use it? I expected pressing 2->X->2->= would result in 4, but it results in 22, then 0. I managed to do this calculation by pressing 2->=->2->X (display shows 2, 0, 2, then 4). It is so unintuitive that I thought UI has some kind of race condition or broken click handler.

[Yatekii]

No, the logic is broken. It is just good in terms of layouting/styling.

[fschutt]

This was probably fixed by #85, reopen if you still have issues.