Tried to take element size of non-array type Field

[jfecher]

Aim

Tried to run the following code:

fn main(x: bool) {
    let alloc = &mut 0;
    let mut array = [alloc];
    *array[0] = 2;
}

Expected Behavior

Expected the code to compile

Bug

Nargo panics with

The application panicked (crashed).
Message:  Uncaught type error: tried to take element size of non-array type Field
Location: crates/noirc_evaluator/src/ssa_refactor/ssa_gen/context.rs:589

This is a bug. We may have already fixed this in newer versions of Nargo so try searching for similar issues at https://github.com/noir-lang/noir/issues/.
If there isn't an open issue for this bug, consider opening one at https://github.com/noir-lang/noir/issues/new?labels=bug&template=bug_report.yml

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                                ⋮ 13 frames hidden ⋮                              
  14: noirc_evaluator::ssa_refactor::ssa_gen::context::FunctionContext::element_size::hbfbc6aa14f1205d4
      at /.../noir/crates/noirc_evaluator/src/ssa_refactor/ssa_gen/context.rs:589
  15: noirc_evaluator::ssa_refactor::ssa_gen::context::FunctionContext::assign_new_value::ha0e10abe0dabe327
      at /.../noir/crates/noirc_evaluator/src/ssa_refactor/ssa_gen/context.rs:562
  16: noirc_evaluator::ssa_refactor::ssa_gen::<impl noirc_evaluator::ssa_refactor::ssa_gen::context::FunctionContext>::codegen_assign::h586d83df2f6900cf
      at /.../noir/crates/noirc_evaluator/src/ssa_refactor/ssa_gen/mod.rs:405
  17: noirc_evaluator::ssa_refactor::ssa_gen::<impl noirc_evaluator::ssa_refactor::ssa_gen::context::FunctionContext>::codegen_expression::hc6ba5540ea9c2fa3
      at /.../noir/crates/noirc_evaluator/src/ssa_refactor/ssa_gen/mod.rs:88
  18: noirc_evaluator::ssa_refactor::ssa_gen::<impl noirc_evaluator::ssa_refactor::ssa_gen::context::FunctionContext>::codegen_block::h259d073623f1ca75
      at /.../noir/crates/noirc_evaluator/src/ssa_refactor/ssa_gen/mod.rs:162
  19: noirc_evaluator::ssa_refactor::ssa_gen::<impl noirc_evaluator::ssa_refactor::ssa_gen::context::FunctionContext>::codegen_expression::hc6ba5540ea9c2fa3
      at /.../noir/crates/noirc_evaluator/src/ssa_refactor/ssa_gen/mod.rs:72
  20: noirc_evaluator::ssa_refactor::ssa_gen::<impl noirc_evaluator::ssa_refactor::ssa_gen::context::FunctionContext>::codegen_function_body::h9821399ac8bcac74
      at /.../noir/crates/noirc_evaluator/src/ssa_refactor/ssa_gen/mod.rs:63
  21: noirc_evaluator::ssa_refactor::ssa_gen::generate_ssa::hd8d0bff39973686d
      at /.../noir/crates/noirc_evaluator/src/ssa_refactor/ssa_gen/mod.rs:44
  22: noirc_evaluator::ssa_refactor::optimize_into_acir::h12639e2bf02acae3
      at /.../noir/crates/noirc_evaluator/src/ssa_refactor.rs:38
  23: noirc_evaluator::ssa_refactor::experimental_create_circuit::h0ba1f0deee1e6458
      at /.../noir/crates/noirc_evaluator/src/ssa_refactor.rs:80
  24: noirc_driver::compile_no_check::h533738fd7760537b
      at /.../noir/crates/noirc_driver/src/lib.rs:313
  25: noirc_driver::compile_main::h949a98290a2050f7
      at /.../noir/crates/noirc_driver/src/lib.rs:202
  26: nargo_cli::cli::compile_cmd::compile_circuit::hdea40452f16a43eb
      at /.../noir/crates/nargo_cli/src/cli/compile_cmd.rs:128
  27: nargo_cli::cli::prove_cmd::prove_with_path::h438ea682d49fe1d7
      at /.../noir/crates/nargo_cli/src/cli/prove_cmd.rs:112
  28: nargo_cli::cli::prove_cmd::run::hf530d941a1673c8b
      at /.../noir/crates/nargo_cli/src/cli/prove_cmd.rs:68
  29: nargo_cli::cli::start_cli::h43751d4bccc346c7
      at /.../noir/crates/nargo_cli/src/cli/mod.rs:80
  30: nargo::main::h6191217e448fb3f7
      at /.../noir/crates/nargo_cli/src/main.rs:14
  31: core::ops::function::FnOnce::call_once::ha1dae44d13ecbe00
      at /rustc/69f9c33d71c871fc16ac445211281c6e7a340943/library/core/src/ops/function.rs:251
                                ⋮ 13 frames hidden ⋮                              
exit 101

To Reproduce

Installation Method

None

Nargo Version

No response

Additional Context

No response

Would you like to submit a PR for this Issue?

No

Support Needs

No response

[jfecher]

This is partly caused by *array[0] = 2; being parsed as (*array)[0] = 2 rather than *(array[0]) = 2;. Although I would think the type checker should flag a dereference of an array as invalid in that case.