I expected this code to return "error" but instead it panics: #[wasm_bindgen] pub fn foo() -> String { let res = std::panic::catch_unwind(|| panic!()); match res { Ok(_) => "success".to_string(), Err(_) => "error".to_string(), } } So it seems like std::panic::catch_unwi…

In short, wasm32-unknown-unknown is panic="abort" by default: Related issue C unwind proposal

Thanks for the links! At least I just figured out that I can catch the abort at the javascript side with normal try catch.

Note that when you catch an exception on the javascript side, it is not safe to call any method on that specific wasm instance anymore. You need to recreate the wasm instance from scratch. Because of panic=abort, no cleanup code gets run, which may mean that unsafe code has left values in an inconsi…

Catch panic in Wasm

help

camden-smallwood March 29, 2021, 3:43am 2

In short, wasm32-unknown-unknown is panic="abort" by default:

Related issue
C unwind proposal

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Catch panic in Wasm

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