Compilation error exit code {compile_result.exit_code} {comp

Error message

Compilation error exit code {compile_result.exit_code}
{compile_result.stderr}

What it means

_compile_code runs ./compile inside the MorphCloud VM workspace and raises RuntimeError with the exit code and stderr when compilation fails. This is the VM-side build of the submission (plus task graders), so a failure means the submitted source does not compile in the sandbox toolchain.

Source

Thrown at src/open_r1/utils/competitive_programming/morph_client.py:182

        return True

    async def _compile_code(self, instance: Instance) -> InstanceExecResponse:
        """
        Compile the code on the instance.

        Args:
            instance: The MorphCloud instance

        Returns:
            InstanceExecResponse: Result of compilation

        Raises:
            RuntimeError: If compilation fails
        """
        compile_result = await instance.aexec("cd /workspace && ./compile")

        if compile_result.exit_code != 0:
            raise RuntimeError(f"Compilation error exit code {compile_result.exit_code}\n{compile_result.stderr}")

        return compile_result

    async def _run_tests(self, instance: Instance, data: Dict[str, Any]) -> Tuple[str, str]:
        """
        Run tests and evaluate results.

        Args:
            instance: The MorphCloud instance
            data: Dictionary containing runtime parameters

        Returns:
            tuple: (score, feedback)

        Raises:
            TimeoutError: If test execution times out
        """
        hard_timeout = data["run_timeout"] / 1000 + 3

View on GitHub (pinned to 1416fa0cf2)

Solutions

Read stderr in the error message — it contains the compiler diagnostics; fix the offending lines in the submission.
Compile the same source locally with the same compiler/standard the IOI package uses to reproduce and fix errors quickly.
Verify all required files (solution + graders) were uploaded to /workspace with the layout ./compile expects.
If you control the sandbox, ensure the compile script and toolchain version match the expected IOI environment.

Example fix

// before: fails on older sandbox gcc
for (auto x : views::iota(0, n)) { ... }
// after: C++17-compatible loop
for (int i = 0; i < n; ++i) { ... }

Defensive patterns

Strategy: validation

Validate before calling

import subprocess
res = subprocess.run(['g++', '-std=c++17', '-fsyntax-only', solution_path], capture_output=True, text=True)
if res.returncode != 0:
    raise RuntimeError(f'Pre-submission compile check failed:\n{res.stderr}')

Type guard

def compile_ok(result) -> bool:
    return getattr(result, 'exit_code', 1) == 0

Try / catch

try:
    score, feedback = await morph_client.execute(data)
except RuntimeError as e:
    if 'Compilation error' in str(e):
        logger.error('Submission failed to compile in sandbox:\n%s', e)
        return '0', 'Compilation error'
    raise

Prevention

Compile locally with the sandbox's compiler standard before batch submission
Avoid bleeding-edge language features not guaranteed on the worker image
Ensure grader sources are uploaded with the correct paths
Run a smoke submission per problem before full evaluation

When it happens

Trigger: instance.aexec('cd /workspace && ./compile') returns exit_code != 0 — submitted C++/C source has compile errors, uses unsupported flags/standard, or the task's grader sources are missing/incompatible so the compile script aborts.

Common situations: Solution uses C++20 features while the sandbox compiler defaults to an older standard; missing #include for functions used; grader files not uploaded to /workspace; compile script failing because problem files were placed in the wrong paths.

Related errors

AI-assisted analysis of huggingface/open-r1@1416fa0cf2 (2026-08-30). Data as JSON: /api/errors/abed27562922efc0. Report an issue: GitHub.