rust-lldb fails to load on LLDB 8.0.0

[zmitchell]

When I run rust-lldb I get the following error:

$ rust-lldb target/debug/myprogram
(lldb) command script import "/Users/zmitchell/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/etc/lldb_rust_formatters.py"
error: module importing failed: loading unimplemented

I'm not sure where to begin debugging this issue. Is it a problem with the Python version used by lldb? Is it an error in the lldb_rust_formatters.py script?

This is on macOS 10.15, though I had the problem on 10.14 as well. I have rustup 1.19.0, lldb 8.0.0, and the 1.38.0 stable toolchain.

Is there anything you'd recommend looking at or do you have any other guidance?

[Mark-Simulacrum]

Just to check, that file exists, right?

Other than that not sure really how to debug this. Which version of python are you using?

[zmitchell]

That file does exist. I'm using Python 3.7.2 installed via pyenv.

[pnkfelix]

Visiting for wg-debugging triage

Our best guess (see conversation here) is that this has to do with a change in LLDB 8.

First step would probably be for one of the local developers to replicate the problem locally (or check if it has been resolved, somehow).

[pnkfelix]

This thread for crystal-lang ran into same issue ("(lldb) command script import /Users/xxx/Work/crystal/etc/lldb/crystal_formatters.py error: module importing failed: loading unimplemented.")

and its filled with lots of ideas of things to investigate

https://forum.crystal-lang.org/t/debugger-support/1325/162

[pnkfelix]

@rustbot label: P-medium

[zmitchell]

As followup I no longer see an issue. This is my system configuration now:
macOS 12.3.1 on M1 Max

$ rust-lldb --version
lldb-1316.0.9.41
Apple Swift version 5.6 (swiftlang-5.6.0.323.62 clang-1316.0.20.8)
$ rustc -V
rustc 1.65.0 (897e37553 2022-11-02)

Loading a brand new binary crate works just fine:

$ cargo new --bin lldb_test
$ cd lldb_test; cargo build
$ rust-lldb target/debug/lldb_test
(lldb) command script import "/Users/zmitchell/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/etc/lldb_lookup.py"
(lldb) command source -s 0 '/Users/zmitchell/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/etc/lldb_commands'
Executing commands in '/Users/zmitchell/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/etc/lldb_commands'.
(lldb) type synthetic add -l lldb_lookup.synthetic_lookup -x ".*" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^(alloc::([a-z_]+::)+)String$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^&(mut )?str$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^&(mut )?\\[.+\\]$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^(std::ffi::([a-z_]+::)+)OsString$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^(alloc::([a-z_]+::)+)Vec<.+>$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^(alloc::([a-z_]+::)+)VecDeque<.+>$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^(alloc::([a-z_]+::)+)BTreeSet<.+>$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^(alloc::([a-z_]+::)+)BTreeMap<.+>$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^(std::collections::([a-z_]+::)+)HashMap<.+>$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^(std::collections::([a-z_]+::)+)HashSet<.+>$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^(alloc::([a-z_]+::)+)Rc<.+>$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^(alloc::([a-z_]+::)+)Arc<.+>$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^(core::([a-z_]+::)+)Cell<.+>$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^(core::([a-z_]+::)+)Ref<.+>$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^(core::([a-z_]+::)+)RefMut<.+>$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^(core::([a-z_]+::)+)RefCell<.+>$" --category Rust
(lldb) type summary add -F lldb_lookup.summary_lookup  -e -x -h "^core::num::([a-z_]+::)*NonZero.+$" --category Rust
(lldb) type category enable Rust
(lldb) target create "target/debug/lldb_test"
Current executable set to '/Users/zmitchell/code/lldb_test/target/debug/lldb_test' (arm64).