jax-ml/jax · error · RuntimeError

{err_msg} (set JAX_PLATFORMS='' to automatically choose an a

Error message

{err_msg} (set JAX_PLATFORMS='' to automatically choose an available backend)

What it means

Error "{err_msg} (set JAX_PLATFORMS='' to automatically choose an available backend)" thrown in jax-ml/jax.

Source

Thrown at jax/_src/xla_bridge.py:842

          continue

        backend = _init_backend(platform)
        _backends[platform] = backend

        if priority > default_priority:
          _default_backend = backend
          default_priority = priority
      except Exception as err:
        err_msg = f"Unable to initialize backend '{platform}': {err}"
        if fail_quietly:
          _backend_errors[platform] = str(err)
          logger.info(err_msg)
        else:
          if config.jax_platforms.value:
            err_msg += " (set JAX_PLATFORMS='' to automatically choose an available backend)"
          else:
            err_msg += " (you may need to uninstall the failing plugin package, or set JAX_PLATFORMS=cpu to skip this backend.)"
          raise RuntimeError(err_msg)

    assert _default_backend is not None
    if not config.jax_platforms.value:
      _suggest_missing_backends()
    return _backends

# Code to suggest plugins that should be installed.
#
# Plugin vendors are welcome to add code to this list, assuming there's a
# lightweight way to determine if hardware is present without requiring
# the relevant plugin be installed.

def _suggest_missing_backends():
  if py_platform.system() != "Linux":
    # If you're not using Linux (or WSL2), we don't have any suggestions at the
    # moment.
    return

View on GitHub (pinned to 1e1c6a8fc0)

When it happens

Trigger: Thrown at jax/_src/xla_bridge.py:842 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of jax-ml/jax@1e1c6a8fc0 (2026-08-27). Data as JSON: /api/errors/bad8a78fbfa2b202. Report an issue: GitHub.