wast's formatting bug on parsing failure leading to rustc panic #2262
Description
Stack trace:
Failed to parse WAT code:
thread 'main' panicked at .cargo/registry/src/index.crates.io-1949cf8c6b5b557f/wast-235.0.0/src/error.rs:150:9:
Formatting argument out of range
stack backtrace:
0: __rustc::rust_begin_unwind
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/panicking.rs:697:5
1: core::panicking::panic_fmt
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/panicking.rs:75:14
2: core::fmt::rt::Argument::from_usize
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/fmt/rt.rs:161:13
3: <wast::error::Error as core::fmt::Display>::fmt
at .cargo/registry/src/index.crates.io-1949cf8c6b5b557f/wast-235.0.0/src/error.rs:150:9
4: core::fmt::rt::Argument::fmt
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/fmt/rt.rs:181:76
5: core::fmt::write
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/fmt/mod.rs:1446:25
6: std::io::default_write_fmt
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/io/mod.rs:639:11
7: std::io::Write::write_fmt
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/io/mod.rs:1914:13
8: <&std::io::stdio::Stderr as std::io::Write>::write_fmt
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/io/stdio.rs:1066:9
9: <std::io::stdio::Stderr as std::io::Write>::write_fmt
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/io/stdio.rs:1040:9
10: std::io::stdio::print_to
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/io/stdio.rs:1164:21
11: std::io::stdio::_eprint
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/io/stdio.rs:1286:5
Debug print shows the following before the panic:
Failed to parse WAT code: Error { inner: ErrorInner { text: Some(Text { line: 5, col: 192586, snippet: " (local i64 i64 i64 i64 i64 i64 i64 i64 i64 i64 i64 i64 i64 i64 ... ... ... i64 i64" }), file: None, span: Span { offset: 192729 }, kind: Custom("expected `)`") } }
Test case:
wasm file: 5da873c7eff9ddd4769471706dbfb11bc10cb1d1378c728ea57ed6228fb3a292.wasm.txt
wat file: 5da873c7eff9ddd4769471706dbfb11bc10cb1d1378c728ea57ed6228fb3a292.wat.txt
I used wasm-tools print to convert the wasm file to a wat file and later used the wast crate to parse the generated wat file. wasm-tools print generates incomplete wat code while showing the following error:
error: function exceeds the maximum number of locals that can be printed