internal error: relating different kinds: jni::objects::JObject<'?14> '?1

[koutheir]

Code

Compiling the following function causes an internal compiler error:

fn empty_string_array(env: jni::JNIEnv) {
    env.new_object_array(
        0,
        jni::objects::JObject::null(),
        jni::objects::JObject::null()
    );
}

Notice that the code above does not make sense as is, but it is a minimal example that still causes the compiler error.

Meta

rustc --version --verbose:

rustc 1.78.0 (9b00956e5 2024-04-29)
binary: rustc
commit-hash: 9b00956e56009bab2aa15d7bff10916599e3d6d6
commit-date: 2024-04-29
host: x86_64-unknown-linux-gnu
release: 1.78.0
LLVM version: 18.1.2

Error output

error: internal compiler error: compiler/rustc_infer/src/infer/at.rs:400:21: relating different kinds: jni::objects::JObject<'?14> '?1

Backtrace

error: internal compiler error: compiler/rustc_infer/src/infer/at.rs:400:21: relating different kinds: jni::objects::JObject<'?14> '?1

thread 'rustc' panicked at compiler/rustc_middle/src/util/bug.rs:35:44:
Box<dyn Any>
stack backtrace:
   0: std::panicking::begin_panic::<rustc_errors::ExplicitBug>
   1: <rustc_errors::diagnostic::BugAbort as rustc_errors::diagnostic::EmissionGuarantee>::emit_producing_guarantee
   2: rustc_middle::util::bug::opt_span_bug_fmt::<rustc_span::span_encoding::Span>::{closure#0}
   3: rustc_middle::ty::context::tls::with_opt::<rustc_middle::util::bug::opt_span_bug_fmt<rustc_span::span_encoding::Span>::{closure#0}, !>::{closure#0}
   4: rustc_middle::ty::context::tls::with_context_opt::<rustc_middle::ty::context::tls::with_opt<rustc_middle::util::bug::opt_span_bug_fmt<rustc_span::span_encoding::Span>::{closure#0}, !>::{closure#0}, !>
   5: rustc_middle::util::bug::bug_fmt
   6: <rustc_middle::ty::generic_args::GenericArg as rustc_infer::infer::at::ToTrace>::to_trace
   7: <rustc_infer::infer::at::At>::eq::<rustc_middle::ty::generic_args::GenericArg>
   8: <rustc_infer::infer::error_reporting::TypeErrCtxt as rustc_trait_selection::traits::error_reporting::type_err_ctxt_ext::InferCtxtPrivExt>::report_similar_impl_candidates
   9: <rustc_infer::infer::error_reporting::TypeErrCtxt as rustc_trait_selection::traits::error_reporting::type_err_ctxt_ext::InferCtxtPrivExt>::try_to_add_help_message
  10: <rustc_infer::infer::error_reporting::TypeErrCtxt as rustc_trait_selection::traits::error_reporting::type_err_ctxt_ext::TypeErrCtxtExt>::report_selection_error
  11: <rustc_infer::infer::error_reporting::TypeErrCtxt as rustc_trait_selection::traits::error_reporting::type_err_ctxt_ext::InferCtxtPrivExt>::report_fulfillment_error
  12: <rustc_infer::infer::error_reporting::TypeErrCtxt as rustc_trait_selection::traits::error_reporting::type_err_ctxt_ext::TypeErrCtxtExt>::report_fulfillment_errors
  13: <rustc_hir_typeck::fn_ctxt::FnCtxt>::check_call
  14: <rustc_hir_typeck::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
  15: <rustc_hir_typeck::fn_ctxt::FnCtxt>::check_method_argument_types
  16: <rustc_hir_typeck::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
  17: <rustc_hir_typeck::fn_ctxt::FnCtxt>::check_block_with_expected
  18: <rustc_hir_typeck::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
  19: rustc_hir_typeck::check::check_fn
  20: rustc_hir_typeck::typeck
      [... omitted 1 frame ...]
  21: rustc_hir_analysis::check_crate
  22: rustc_interface::passes::analysis
      [... omitted 1 frame ...]
  23: rustc_interface::interface::run_compiler::<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}
   Compiling toml v0.8.12
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

note: we would appreciate a bug report: https://github.com/rust-lang/rust/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md

note: rustc 1.78.0 (9b00956e5 2024-04-29) running on x86_64-unknown-linux-gnu

note: compiler flags: --crate-type lib -C embed-bitcode=no -C codegen-units=17 -C debuginfo=2 -C incremental=[REDACTED] -C linker-plugin-lto -C linker=clang-18 -C link-arg=-fuse-ld=lld-18

note: some of the compiler flags provided by cargo are hidden

query stack during panic:
#0 [typeck] type-checking `empty_string_array`
#1 [analysis] running analysis passes on this crate
end of query stack
warning: `proc-macro-support` (lib) generated 2 warnings (run `cargo fix --lib -p proc-macro-support` to apply 2 suggestions)
error: could not compile `proc-macro-support` (lib); 2 warnings emitted

[lqd]

Is that using duchess, jni-rs or another jni crate? Do you have a complete example we could look at?

[matthiaskrgr]

#121134 has a reproducer

[workingjubilee]

closing as duplicate.