Can't assert() two arrays when contract compiled via aztec-cli compile

[michaelelliot]

When compiling a simple contract that does an assert(a == b) on two arrays the wasm compiler complains:

$ aztec-cli compile .
Compiling . with wasm backend...
panicked at 'internal error: entered unreachable code: Arrays are invalid in binary operations', compiler/noirc_evaluator/src/brillig/brillig_gen/brillig_block.rs:1340:13

Stack:

Error
    at module.exports.__wbg_new_abda76e883ba8a5f (/usr/src/noir/packages/noir_wasm/nodejs/noir_wasm.js:308:17)
    at console_error_panic_hook::hook::h0dc62071592e511d (wasm://wasm/0250a666:wasm-function[2915]:0x684633)
    at core::ops::function::Fn::call::ha4bfd2d1114566d9 (wasm://wasm/0250a666:wasm-function[7449]:0x74ec17)
    at wasm://wasm/0250a666:wasm-function[4741]:0x717375
    at wasm://wasm/0250a666:wasm-function[5151]:0x72a5ba
    at wasm://wasm/0250a666:wasm-function[7443]:0x74ebe4
    at wasm://wasm/0250a666:wasm-function[5859]:0x73f0f2
    at wasm://wasm/0250a666:wasm-function[6266]:0x746aa9
    at noirc_evaluator::brillig::brillig_gen::brillig_block::BrilligBlock::convert_ssa_binary::h6340c18ff460e390 (wasm://wasm/0250a666:wasm-function[1304]:0x545126)
    at noirc_evaluator::brillig::brillig_gen::brillig_block::BrilligBlock::convert_block::h59d45d2728348b39 (wasm://wasm/0250a666:wasm-function[28]:0x6dacf)

Error in command execution
RuntimeError: unreachable
    at wasm://wasm/0250a666:wasm-function[7570]:0x74efcd
    at wasm://wasm/0250a666:wasm-function[7038]:0x74d87b
    at wasm://wasm/0250a666:wasm-function[4741]:0x7173a5
    at wasm://wasm/0250a666:wasm-function[5151]:0x72a5ba
    at wasm://wasm/0250a666:wasm-function[7443]:0x74ebe4
    at wasm://wasm/0250a666:wasm-function[5859]:0x73f0f2
    at wasm://wasm/0250a666:wasm-function[6266]:0x746aa9
    at noirc_evaluator::brillig::brillig_gen::brillig_block::BrilligBlock::convert_ssa_binary::h6340c18ff460e390 (wasm://wasm/0250a666:wasm-function[1304]:0x545126)
    at noirc_evaluator::brillig::brillig_gen::brillig_block::BrilligBlock::convert_block::h59d45d2728348b39 (wasm://wasm/0250a666:wasm-function[28]:0x6dacf)
    at noirc_evaluator::brillig::brillig_gen::brillig_block::BrilligBlock::compile::h198848e02911a014 (wasm://wasm/0250a666:wasm-function[1150]:0x50d228)

Contract:

contract TestingArrayAssert {
    #[aztec(public)]
    fn test_array_assert(a: [u8; 2], b: [u8; 2]) {
        assert(a == b);
    }
}

Using the latest sandbox and CLI images:

aztecprotocol/cli:latest	    sha256:67325eebfb212404b2660e6d81e79958a08ae1e9f99404574450610f89093e98
aztecprotocol/aztec-sandbox:latest  sha256:7603842a4a3bf1b53bb5e439f754353cc6134fd15bdd5bc35af6c07a928af0a7

$ aztec-cli -V
0.16.9

[rahul-kothari]

Thanks for flagging this - it is a bug which is fixed in noir-lang/noir#3916

This can be worked around using

let predicate = a == b;
assert(predicate)

until the fix is included in a release!