thread 'main' panicked at 'assertion failed: !require_bitcode', src/tools/cargo/src/cargo/core/compiler/lto.rs:49:9

[matthiaskrgr]

Problem
Cargo crashed while running cargo test --verbose --release --all -- --nocapture

Steps

1. git clone https://github.com/matthiaskrgr/cargo-cache
2. cd cargo-cache
3. cargo test --verbose --release --all -- --nocapture

thread 'main' panicked at 'assertion failed: !require_bitcode', src/tools/cargo/src/cargo/core/compiler/lto.rs:49:9
stack backtrace:
   0:     0x5576ca9d9414 - backtrace::backtrace::libunwind::trace::hfcd33194db0151d4
                               at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.46/src/backtrace/libunwind.rs:86
   1:     0x5576ca9d9414 - backtrace::backtrace::trace_unsynchronized::hfd1904bbbd5335b5
                               at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.46/src/backtrace/mod.rs:66
   2:     0x5576ca9d9414 - std::sys_common::backtrace::_print_fmt::h8476c57b177b254e
                               at src/libstd/sys_common/backtrace.rs:78
   3:     0x5576ca9d9414 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h73acbc5f6d4b1044
                               at src/libstd/sys_common/backtrace.rs:59
   4:     0x5576caa0a01c - core::fmt::write::hdf236390fbd68d3d
                               at src/libcore/fmt/mod.rs:1069
   5:     0x5576ca9d0263 - std::io::Write::write_fmt::h5722fa40bb2afafd
                               at src/libstd/io/mod.rs:1532
   6:     0x5576ca9dd855 - std::sys_common::backtrace::_print::ha468e873aada7c78
                               at src/libstd/sys_common/backtrace.rs:62
   7:     0x5576ca9dd855 - std::sys_common::backtrace::print::h149365a2f029de62
                               at src/libstd/sys_common/backtrace.rs:49
   8:     0x5576ca9dd855 - std::panicking::default_hook::{{closure}}::hb4a33f9e05934a52
                               at src/libstd/panicking.rs:198
   9:     0x5576ca9dd592 - std::panicking::default_hook::hc4535d7b0c743abd
                               at src/libstd/panicking.rs:218
  10:     0x5576ca9dde98 - std::panicking::rust_panic_with_hook::haa34a96a6dbd5a2e
                               at src/libstd/panicking.rs:477
  11:     0x5576ca1c795e - std::panicking::begin_panic::h54777bf21989e629
  12:     0x5576ca3fd96d - cargo::core::compiler::lto::calculate::h2c312886d32a1e71
  13:     0x5576ca3fd655 - cargo::core::compiler::lto::calculate::h2c312886d32a1e71
  14:     0x5576ca3fd400 - cargo::core::compiler::lto::generate::hcdd45fe57c462183
  15:     0x5576ca167ced - cargo::core::compiler::context::Context::compile::hf7238f9b1b494d22
  16:     0x5576ca17aacb - cargo::ops::cargo_compile::compile_ws::hdf6433bf0283fe69
  17:     0x5576ca17a829 - cargo::ops::cargo_compile::compile::h97828d679d0d8fb3
  18:     0x5576ca42259d - cargo::ops::cargo_test::run_tests::hc9fee41bd4cdba5f
  19:     0x5576ca0e9f8a - cargo::commands::test::exec::hcb9e98bd91b0a043
  20:     0x5576ca0a3fa9 - cargo::cli::main::h4be78871f8deb501
  21:     0x5576ca1004b9 - cargo::main::h9724f8a40f7eb19e
  22:     0x5576ca0dd813 - std::rt::lang_start::{{closure}}::h8a8f11796b55167b
  23:     0x5576ca9de338 - std::rt::lang_start_internal::{{closure}}::h8ee41efd8ae7ff76
                               at src/libstd/rt.rs:52
  24:     0x5576ca9de338 - std::panicking::try::do_call::h0a4c4514ee6ebbfc
                               at src/libstd/panicking.rs:297
  25:     0x5576ca9de338 - std::panicking::try::h7c2f3858e42d7516
                               at src/libstd/panicking.rs:274
  26:     0x5576ca9de338 - std::panic::catch_unwind::h76c4030fa5655c1e
                               at src/libstd/panic.rs:394
  27:     0x5576ca9de338 - std::rt::lang_start_internal::h1c1398259f72ace6
                               at src/libstd/rt.rs:51
  28:     0x5576ca102a02 - main
  29:     0x7ff6a3efb023 - __libc_start_main
  30:     0x5576ca093029 - <unknown>

Possible Solution(s)

Notes

Output of cargo version:
cargo 1.45.0-nightly (f534844c2 2020-05-06)

[matthiaskrgr]

The assertion was added in #8192

[matthiaskrgr]

Cargo no longer panics if I remove the lto = field from my Cargo.toml

[hbina]

I cannot reproduce this on my end.

[matthiaskrgr]

Did you make sure that you are on latest nightly (rustc 1.45.0-nightly (a08c47310 2020-05-07))?

This happens on my GHA setup as well.

[hbina]

ah yes, cargo +nightly test --verbose --release --all -- --nocapture immediately fails that assertion.

[alexcrichton]

Thanks for the bug report and reproduction steps! This shoudl be fixed in #8226.