oven-sh/bun · error · Error

Duplicate private name "${name}" in BunBuiltinNames.h

Error message

Duplicate private name "${name}" in BunBuiltinNames.h

What it means

Error "Duplicate private name "${name}" in BunBuiltinNames.h" thrown in oven-sh/bun.

Source

Thrown at src/codegen/bundle-functions.ts:808

      "#define BUN_COMMON_PRIVATE_IDENTIFIERS_EACH_PROPERTY_NAME",
    );
    let definedBuiltinNamesMacroEndI = BunBuiltinNamesHeader.indexOf(
      "--- END of BUN_COMMON_PRIVATE_IDENTIFIERS_EACH_PROPERTY_NAME ---",
    );
    const definedBuiltinNames = BunBuiltinNamesHeader.slice(definedBuiltinNamesStartI, definedBuiltinNamesMacroEndI)
      .split("\n")
      .map(x => x.trim())
      .filter(x => x.startsWith("macro("))
      .map(x => x.slice(x.indexOf("(") + 1, x.indexOf(")")))
      .map(x => x.trim())
      .sort();

    const uniqueDefinedBuiltinNames = new Set();
    for (let name of definedBuiltinNames) {
      const prevSize = uniqueDefinedBuiltinNames.size;
      uniqueDefinedBuiltinNames.add(name);
      if (uniqueDefinedBuiltinNames.size === prevSize) {
        throw new Error(`Duplicate private name "${name}" in BunBuiltinNames.h`);
      }
    }
    for (let additionalPrivateName of additionalPrivateNames) {
      if (uniqueDefinedBuiltinNames.has(additionalPrivateName)) {
        additionalPrivateNames.delete(additionalPrivateName);
      }
    }

    let additionalPrivateNamesHeader = `// Generated by ${import.meta.path}
#pragma once

#ifndef BUN_ADDITIONAL_BUILTIN_NAMES
#define BUN_ADDITIONAL_BUILTIN_NAMES(macro) \\
  ${Array.from(additionalPrivateNames)
    .map(x => `macro(${x})`)
    .join(" \\\n  ")}
#endif
`;

View on GitHub (pinned to 8c5296ac45)

When it happens

Trigger: Thrown at src/codegen/bundle-functions.ts:808 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of oven-sh/bun@8c5296ac45 (2026-08-16). Data as JSON: /api/errors/c2988f579585e819. Report an issue: GitHub.