0x prefix inconsistent in object

[r1cs]

Component

Forge

Have you ensured that all of these are up to date?

• Foundry
• Foundryup

What version of Foundry are you on?

forge 0.1.0 (ff4ec0f 2022-02-15T00:28:49.003614+00:00)

What command(s) is the bug in?

forge build

Operating System

macOS (M1)

Describe the bug

when I build contract, some object filed in bytecode&deployed_bytecode missing 0x prefix.making strict check for hex string failed.
Here is different object filed prefix with same command:
A contract:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

//import "../console.sol";
import "./MachineState.sol";
contract MemoryTest {
\\\
\\\
\\\
}

and out in bytecode filed:

"bytecode": {
 "object": "6080604052..."
  "sourceMap": "114:1488:18:-:0;;;;;;;;;;;;;;;;;;;",
"linkReferences": {
      "/Users/w/w/r/r/cs/r/Register.sol": {
        "Register": [
          {
            "start": 3692,
            "length": 20
          },
          {
            "start": 3885,
            "length": 20
          }
        ]
      }


}

but in contract B:

// SPDX-License-Identifier: GPL-v3
pragma solidity ^0.8.0;

import "../interfaces/IMemory.sol";
library MemoryLayout {
///
///
}

the output in bytecode fild is:

"bytecode": {
"object": "0x610196..."
"sourceMap": "97:1376:1..."
"linkReferences": {}
}

It seems that compiler treat library and contract differently, making object output format not consistent.

[mattsse]

thanks for the repro!
will take a look if that's due some serde settings in ethers-rs

[mattsse]

this happens because the MemoryTest has links and serialized as Bytecode::Unlinked
and string serialisation does not add 0x prefix,
I wonder what the consistent format should we, always 0x prefixed or never, like hardhat @gakonst?