nodejs/node · error · Exception

--depfile requires --stamp and vice versa

Error message

--depfile requires --stamp and vice versa

What it means

concatenate_protocols.py merges several .pdl protocol files into one and, like code_generator.py, requires --depfile and --stamp as a pair. The guard is the same XOR check `bool(depfile) != bool(stamp)`; passing only one aborts before any concatenation happens.

Source

Thrown at deps/inspector_protocol/concatenate_protocols.py:25

import sys
import argparse

try:
  import json
except ImportError:
  import simplejson as json

import pdl

def main(argv):
  cmdline_parser = argparse.ArgumentParser()
  cmdline_parser.add_argument('filename', nargs='*')
  cmdline_parser.add_argument("--depfile", required=False)
  cmdline_parser.add_argument("--stamp", required=False)
  arg_options = cmdline_parser.parse_args()

  if bool(arg_options.depfile) != bool(arg_options.stamp):
    raise Exception("--depfile requires --stamp and vice versa")

  if len(arg_options.filename) < 1:
    sys.stderr.write(
        "Usage: %s <protocol-1> [<protocol-2> [, <protocol-3>...]] "
        "<output-file>\n" % sys.argv[0])
    return 1

  filenames = arg_options.filename
  deps_filename = arg_options.depfile
  stamp_filename = arg_options.stamp
  domains = []
  source_set = set()
  version = None
  for protocol in filenames[:-1]:
    file_name = os.path.normpath(protocol)
    if not os.path.isfile(file_name):
      sys.stderr.write("Cannot find %s\n" % file_name)
      return 1

View on GitHub (pinned to 1b2de5e052)

Solutions

1. Pass both --depfile and --stamp, or neither.
2. Mirror the arguments you pass to code_generator.py when chaining the two scripts.
3. Audit the gn/gyp template for concatenate_protocols and ensure both flags are templated together.

Example fix

# before
python concatenate_protocols.py js_protocol.json out.pdl --depfile d.d
# after
python concatenate_protocols.py js_protocol.json out.pdl --depfile d.d --stamp out.stamp

if bool(args.depfile) != bool(args.stamp):
    raise SystemExit('--depfile and --stamp must be supplied together or both omitted')

When it happens

Trigger: Raised in main() when exactly one of the optional --depfile / --stamp argparse arguments is provided, before the required positional <output-file> is even read.

Common situations: Build rule refactors that propagated --depfile from the code_generator step but dropped --stamp here; CI that injects depfile flags globally; hand-running the script during protocol development.

Related errors

• --depfile requires --stamp and vice versa
• Dictionary key is not a string.
• Dictionary key is not a valid GN identifier.
• Unsupported type when printing to GN.
• --enable-v8windbg is incompatible with --without-bundled-v8.

AI-assisted analysis of nodejs/node@1b2de5e052 (2026-08-13). Data as JSON: /api/errors/4f0176961a2f17d8. Report an issue: GitHub.