thread 'rustc' panicked at rust-nightly/compiler/rustc_errors/src/diagnostic.rs:1006:9

wxie7 commented 4 days ago

I tried this code:

use rand::{thread_rng, Rng};
use std::env;
use std::fs::{self, File};
use std::io::{self, Read, Write};
use std::process::{Command, Stdio};
use std::sync::{Arc, Mutex};
use std::thread;
use std::time::{Duration, Instant};
fn main() {
    let args: Vec<String> = env::args().collect();
    let now = Instant::now();
    let data = fs::read_to_string(&args[1].replace("v2", "")).expect("Unable to open the file");
    let mut v = data;
    for _i in 0..10 {
        v = v
            .chars()
            .filter(|x| !x.is_whitespace())
            .map(|x| {
                println!("Child spawned with the size: {}", x);
            })
            .collect::<String>();
    }
    fs::write(&args[1].replace(".txt", "v3"), v).expect("Unable to write");
    println!("{}s to complete", now.elapsed().as_secs_f32());
}

I expected to see this happen: explanation

Instead, this happened: explanation

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rustc --version --verbose:


commit-date: unknown
host: x86_64-unknown-linux-gnu
release: 1.85.0-dev
LLVM version: 19.1.4

Backtrace

``` thread 'rustc' panicked at /data/xieym/workspace/rust/rust-nightly/compiler/rustc_errors/src/diagnostic.rs:1006:9: Span must not be empty and have no suggestion stack backtrace: 0: 0x7fbedf28dead - ::fmt::h51e5276f25f67b8a 1: 0x7fbedf347ea3 - core::fmt::write::h0a73bee6158cdbf1 2: 0x7fbedf2b4309 - std::io::Write::write_fmt::h206d582822858877 3: 0x7fbedf28dd53 - std::sys::backtrace::BacktraceLock::print::h84a9a4c750ade733 4: 0x7fbedf2c46fc - std::panicking::default_hook::{{closure}}::h216e29259e3d5cff 5: 0x7fbedf2c44c5 - std::panicking::default_hook::h03ce982d60640bc4 6: 0x7fbedab6be42 - as core[dcda4f281d996093]::ops::function::Fn<(&dyn for<'a, 'b> core[dcda4f281d996093]::ops::function::Fn<(&'a std[31742bae037c253]::panic::PanicHookInfo<'b>,), Output = ()> + core[dcda4f281d996093]::marker::Send + core[dcda4f281d996093]::marker::Sync, &std[31742bae037c253]::panic::PanicHookInfo)>>::call 7: 0x7fbedf2c4e68 - std::panicking::rust_panic_with_hook::h88b680004200a63a 8: 0x7fbedf28e33a - std::panicking::begin_panic_handler::{{closure}}::ha56090df9488ab86 9: 0x7fbedf28e169 - std::sys::backtrace::__rust_end_short_backtrace::h8833a10924a5c2d2 10: 0x7fbedf2c47ed - rust_begin_unwind 11: 0x7fbedf352a40 - core::panicking::panic_fmt::h57d6d212ea0ce749 12: 0x7fbeddea5575 - ::span_suggestion_with_style::<&str, alloc[7c2d8435141f8e1e]::string::String> 13: 0x7fbeddba70ef - ::point_at_chain:: 14: 0x7fbeddba5f96 - ::note_function_argument_obligation:: 15: 0x7fbeddb9fa32 - ::note_obligation_cause_code:: 16: 0x7fbeddb86125 - ::note_obligation_cause 17: 0x7fbeddb7af45 - ::report_selection_error 18: 0x7fbeddbc2394 - ::report_fulfillment_error 19: 0x7fbeddbacb07 - ::report_fulfillment_errors 20: 0x7fbedb244ff9 - ::check_argument_types 21: 0x7fbedb244372 - ::check_method_argument_types 22: 0x7fbedb2bb5eb - ::check_expr_kind 23: 0x7fbedb21ebdf - ::check_expr_with_expectation_and_args 24: 0x7fbedb2afdc5 - ::check_expr_with_expectation 25: 0x7fbedb2b487f - ::check_expr_kind 26: 0x7fbedb21ebdf - ::check_expr_with_expectation_and_args 27: 0x7fbedb2afdc5 - ::check_expr_with_expectation 28: 0x7fbedb251056 - ::check_expr_block 29: 0x7fbedb2b1982 - ::check_expr_kind 30: 0x7fbedb21ebdf - ::check_expr_with_expectation_and_args 31: 0x7fbedb2afdc5 - ::check_expr_with_expectation 32: 0x7fbedb2b70e1 - ::check_expr_kind 33: 0x7fbedb21ebdf - ::check_expr_with_expectation_and_args 34: 0x7fbedb2afdc5 - ::check_expr_with_expectation 35: 0x7fbedb250f2c - ::check_expr_block 36: 0x7fbedb2b502c - ::check_expr_kind 37: 0x7fbedb21ebdf - ::check_expr_with_expectation_and_args 38: 0x7fbedb2afdc5 - ::check_expr_with_expectation 39: 0x7fbedb2b70e1 - ::check_expr_kind 40: 0x7fbedb21ebdf - ::check_expr_with_expectation_and_args 41: 0x7fbedb2afdc5 - ::check_expr_with_expectation 42: 0x7fbedb2b0726 - ::check_expr_kind 43: 0x7fbedb21ebdf - ::check_expr_with_expectation_and_args 44: 0x7fbedb2afdc5 - ::check_expr_with_expectation 45: 0x7fbedb250f2c - ::check_expr_block 46: 0x7fbedb2b1982 - ::check_expr_kind 47: 0x7fbedb21ebdf - ::check_expr_with_expectation_and_args 48: 0x7fbedb2afdc5 - ::check_expr_with_expectation 49: 0x7fbedb2201bf - ::check_return_or_body_tail 50: 0x7fbedb54b17b - rustc_hir_typeck[c5136c63f534b988]::check::check_fn 51: 0x7fbedb543e2f - rustc_hir_typeck[c5136c63f534b988]::typeck 52: 0x7fbedd347a35 - rustc_query_impl[bec2af351405b693]::plumbing::__rust_begin_short_backtrace::> 53: 0x7fbedd2b7115 - >::call_once 54: 0x7fbedd214d34 - rustc_query_system[1b6cbf762e62559d]::query::plumbing::try_execute_query::, rustc_query_system[1b6cbf762e62559d]::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl[bec2af351405b693]::plumbing::QueryCtxt, false> 55: 0x7fbedd4369fb - rustc_query_impl[bec2af351405b693]::query_impl::typeck::get_query_non_incr::__rust_end_short_backtrace 56: 0x7fbedb7a3e04 - ::par_body_owners::::{closure#0} 57: 0x7fbedb79355d - ::run::<(), rustc_data_structures[8c79ebd7d363ac43]::sync::parallel::par_for_each_in<&rustc_span[37f46e797e36bb53]::def_id::LocalDefId, &[rustc_span[37f46e797e36bb53]::def_id::LocalDefId], ::par_body_owners::{closure#0}>::{closure#0}::{closure#1}::{closure#0}> 58: 0x7fbedb80b8be - rustc_hir_analysis[beef3382d6061d7f]::check_crate 59: 0x7fbedae4d3b1 - rustc_interface[3a875bb8a3a01a82]::passes::analysis 60: 0x7fbedd348053 - rustc_query_impl[bec2af351405b693]::plumbing::__rust_begin_short_backtrace::> 61: 0x7fbedd2b7c41 - >::call_once 62: 0x7fbedd1628fc - rustc_query_system[1b6cbf762e62559d]::query::plumbing::try_execute_query::>, false, false, false>, rustc_query_impl[bec2af351405b693]::plumbing::QueryCtxt, false> 63: 0x7fbedd545338 - rustc_query_impl[bec2af351405b693]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace 64: 0x7fbedab418bb - ::enter::, rustc_span[37f46e797e36bb53]::ErrorGuaranteed>> 65: 0x7fbedaaf665a - >::enter::, rustc_span[37f46e797e36bb53]::ErrorGuaranteed>, rustc_driver_impl[d7b86d9e63f9aaed]::run_compiler::{closure#0}::{closure#1}::{closure#4}> 66: 0x7fbedab0237c - ::enter::, rustc_span[37f46e797e36bb53]::ErrorGuaranteed>> 67: 0x7fbedab321de - >::set::, rustc_driver_impl[d7b86d9e63f9aaed]::run_compiler::{closure#0}>::{closure#1}, core[dcda4f281d996093]::result::Result<(), rustc_span[37f46e797e36bb53]::ErrorGuaranteed>>::{closure#0}, core[dcda4f281d996093]::result::Result<(), rustc_span[37f46e797e36bb53]::ErrorGuaranteed>>::{closure#0}::{closure#0}::{closure#0}, core[dcda4f281d996093]::result::Result<(), rustc_span[37f46e797e36bb53]::ErrorGuaranteed>> 68: 0x7fbedaae44dc - rustc_span[37f46e797e36bb53]::create_session_globals_then::, rustc_interface[3a875bb8a3a01a82]::util::run_in_thread_with_globals, rustc_driver_impl[d7b86d9e63f9aaed]::run_compiler::{closure#0}>::{closure#1}, core[dcda4f281d996093]::result::Result<(), rustc_span[37f46e797e36bb53]::ErrorGuaranteed>>::{closure#0}, core[dcda4f281d996093]::result::Result<(), rustc_span[37f46e797e36bb53]::ErrorGuaranteed>>::{closure#0}::{closure#0}::{closure#0}> 69: 0x7fbedab6f232 - std[31742bae037c253]::sys::backtrace::__rust_begin_short_backtrace::, rustc_driver_impl[d7b86d9e63f9aaed]::run_compiler::{closure#0}>::{closure#1}, core[dcda4f281d996093]::result::Result<(), rustc_span[37f46e797e36bb53]::ErrorGuaranteed>>::{closure#0}, core[dcda4f281d996093]::result::Result<(), rustc_span[37f46e797e36bb53]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[dcda4f281d996093]::result::Result<(), rustc_span[37f46e797e36bb53]::ErrorGuaranteed>> 70: 0x7fbedaaf0574 - <::spawn_unchecked_, rustc_driver_impl[d7b86d9e63f9aaed]::run_compiler::{closure#0}>::{closure#1}, core[dcda4f281d996093]::result::Result<(), rustc_span[37f46e797e36bb53]::ErrorGuaranteed>>::{closure#0}, core[dcda4f281d996093]::result::Result<(), rustc_span[37f46e797e36bb53]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[dcda4f281d996093]::result::Result<(), rustc_span[37f46e797e36bb53]::ErrorGuaranteed>>::{closure#1} as core[dcda4f281d996093]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0} 71: 0x7fbedf30319d - as core::ops::function::FnOnce>::call_once::hc538cfe9cf5a97c8 72: 0x7fbedf2923ab - std::sys::pal::unix::thread::Thread::new::thread_start::h7a196e16c036c2e2 73: 0x7fbed8a3eac3 - start_thread at ./nptl/pthread_create.c:442:8 74: 0x7fbed8ad0850 - __GI___clone3 at ./misc/../sysdeps/unix/sysv/linux/x86_64/clone3.S:81 75: 0x0 - ```

jieyouxu commented 3 days ago

@wxie7 with these fuzzed examples, can you try to trim out the unused dependencies? E.g. in this case this example imports use rand::{thread_rng, Rng}; but it's not actually used, and I can repro the ICE without that. The external deps make it more annoying when it's unrelated errors.

jieyouxu commented 3 days ago

Minimized:

fn main() {
    String::new()
        .chars()
        .map(|x| {
            println!("{}", x);
        })
        .collect::<String>();
}

jieyouxu commented 3 days ago

This is a pain to bisect because it needs debug assertions. Based on looking at code changes, this iter chain type mismatch suggestion introduced in #116717 probably was always reachable by empty spans (due to "inner" type errors or something). cc @estebank for FYI

estebank commented 3 days ago

It can probably be sidestep by adding to

https://github.com/rust-lang/rust/pull/116717/files#diff-aef5d12ac7ec2060165cf1db78128f941c789bb2fc90c7ed351049b0be4d435eR3643

the condition && expr.span.hi() != stmt.span.hi(). I'll check to see what the underlying issue is (the expr.span really shouldn't cover the ;, should it?)

Edit: great. The stmt.span doesn't include the ;. Wonder if that's changed since I added the suggestion, or if the inclusion of the macro call changes things...

jieyouxu commented 3 days ago

Edit: great. The stmt.span doesn't include the ;. Wonder if that's changed since I added the suggestion, or if the inclusion of the macro call changes things...

~~I think that's a long-standing problem IIRC~~. EDIT: nvm a different problem

rust-lang / rust

thread 'rustc' panicked at rust-nightly/compiler/rustc_errors/src/diagnostic.rs:1006:9 #133833

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