dotnet/runtime · error · RuntimeError

Tiering options have no effect for pmi or crossgen2 collecti

Error message

Tiering options have no effect for pmi or crossgen2 collections.

What it means

Thrown by SuperPMICollect.__init__() when the user requests a PMI or crossgen2 collection mode (--pmi or --crossgen2) and simultaneously passes --tiered_compilation or --tiered_pgo. Tiered compilation and tiered PGO are runtime JIT behaviors that only apply when the JIT is invoked through the normal runtime path; PMI and crossgen2 invoke the JIT directly at compile time (AOT-style), making tiering options meaningless and potentially misleading.

Source

Thrown at src/coreclr/scripts/superpmi.py:717

        self.superpmi_path = determine_superpmi_tool_path(coreclr_args)
        self.mcs_path = determine_mcs_tool_path(coreclr_args)

        self.collection_command = coreclr_args.collection_command
        self.collection_args = coreclr_args.collection_args

        if coreclr_args.pmi:
            self.pmi_location = determine_pmi_location(coreclr_args)
            self.corerun = os.path.join(self.core_root, self.corerun_tool_name)

        if coreclr_args.crossgen2:
            self.corerun = os.path.join(self.core_root, self.corerun_tool_name)

        if coreclr_args.pmi or coreclr_args.crossgen2:
            self.assemblies = coreclr_args.assemblies
            self.exclude = coreclr_args.exclude
            if coreclr_args.tiered_compilation or coreclr_args.tiered_pgo:
               raise RuntimeError("Tiering options have no effect for pmi or crossgen2 collections.")

        if coreclr_args.nativeaot:
            self.ilc_rsps = coreclr_args.ilc_rsps
            self.exclude = coreclr_args.exclude
            if coreclr_args.tiered_compilation or coreclr_args.tiered_pgo:
                raise RuntimeError("Tiering options have no effect for nativeaot collections.")

        if coreclr_args.tiered_compilation and coreclr_args.tiered_pgo:
            raise RuntimeError("Pass only one tiering option.")

        self.coreclr_args = coreclr_args

        self.temp_location = None

        # Pathname for a temporary .MCL file used for noticing SuperPMI replay failures against base MCH.
        self.base_fail_mcl_file = None

        # The base .MCH file path

View on GitHub (pinned to 290d5ab72c)

Solutions

1. Remove --tiered_compilation and --tiered_pgo flags when using --pmi or --crossgen2 with superpmi.py collect.
2. If you need tiered compilation data, use the default collection mode (a collection command) instead of --pmi or --crossgen2.
3. Understand that PMI and crossgen2 produce deterministic single-tier output; tiering cannot be applied to these collection types.

Example fix

# before: incompatible flags
python superpmi.py collect --pmi -assemblies ./libs --tiered_pgo

# after: remove tiering flags for pmi/crossgen2
python superpmi.py collect --pmi -assemblies ./libs

# Validate argument compatibility before calling SuperPMICollect
if (coreclr_args.pmi or coreclr_args.crossgen2):
    if coreclr_args.tiered_compilation or coreclr_args.tiered_pgo:
        raise ValueError('Tiering options (--tiered_compilation, --tiered_pgo) are incompatible with --pmi or --crossgen2')

def is_valid_collection_mode_combo(pmi: bool, crossgen2: bool, tiered_compilation: bool, tiered_pgo: bool) -> bool:
    if pmi or crossgen2:
        return not (tiered_compilation or tiered_pgo)
    return True

try:
    collector = SuperPMICollect(coreclr_args)
except RuntimeError as e:
    if 'Tiering options have no effect for pmi or crossgen2' in str(e):
        logging.error('Remove --tiered_compilation and --tiered_pgo when using --pmi or --crossgen2')
        sys.exit(1)
    raise

When it happens

Trigger: At lines 713-717: if coreclr_args.pmi or coreclr_args.crossgen2, and (coreclr_args.tiered_compilation or coreclr_args.tiered_pgo), line 717 raises. The combination is explicitly rejected because tiering has no effect on PMI/crossgen2 compilation.

Common situations: A developer copies flags from a runtime benchmarking command and adds them to a SuperPMI collect command without realizing PMI and crossgen2 don't support tiering. Misunderstanding that SuperPMI PMI collections capture single-tier JIT output for deterministic replay, and tiering would introduce non-determinism.

Related errors

• Tiering options have no effect for nativeaot collections.
• Unsupported OS.
• Pass only one tiering option.
• PMI not found at {}
• Collection 'smoke_tests' is only available for 'nativeaot' c

AI-assisted analysis of dotnet/runtime@290d5ab72c (2026-08-06). Data as JSON: /api/errors/f1359c493218d4de. Report an issue: GitHub.