nodejs/node · error · Exception

Missing input files: %s

Error message

Missing input files:
%s

What it means

When generator_flags['msvs_error_on_missing_sources'] is set, gyp checks that every regular source file (those without a '$' special marker) exists on disk relative to the build dir. Missing files would cause unnecessary recompilation and confusing VS failures; this opt-in check surfaces them early with a normalized path list.

Source

Thrown at tools/gyp/pylib/gyp/msvs_emulation.py:1234

        cl_paths[arch] = _ExtractCLPath(output)
    return cl_paths


def VerifyMissingSources(sources, build_dir, generator_flags, gyp_to_ninja):
    """Emulate behavior of msvs_error_on_missing_sources present in the msvs
    generator: Check that all regular source files, i.e. not created at run time,
    exist on disk. Missing files cause needless recompilation when building via
    VS, and we want this check to match for people/bots that build using ninja,
    so they're not surprised when the VS build fails."""
    if int(generator_flags.get("msvs_error_on_missing_sources", 0)):
        no_specials = filter(lambda x: "$" not in x, sources)
        relative = [os.path.join(build_dir, gyp_to_ninja(s)) for s in no_specials]
        missing = [x for x in relative if not os.path.exists(x)]
        if missing:
            # They'll look like out\Release\..\..\stuff\things.cc, so normalize the
            # path for a slightly less crazy looking output.
            cleaned_up = [os.path.normpath(x) for x in missing]
            raise Exception("Missing input files:\n%s" % "\n".join(cleaned_up))


# Sets some values in default_variables, which are required for many
# generators, run on Windows.
def CalculateCommonVariables(default_variables, params):
    generator_flags = params.get("generator_flags", {})

    # Set a variable so conditions can be based on msvs_version.
    msvs_version = gyp.msvs_emulation.GetVSVersion(generator_flags)
    default_variables["MSVS_VERSION"] = msvs_version.ShortName()

    # To determine processor word size on Windows, in addition to checking
    # PROCESSOR_ARCHITECTURE (which reflects the word size of the current
    # process), it is also necessary to check PROCESSOR_ARCHITEW6432 (which
    # contains the actual word size of the system when running thru WOW64).
    if "64" in os.environ.get("PROCESSOR_ARCHITECTURE", "") or "64" in os.environ.get(
        "PROCESSOR_ARCHITEW6432", ""
    ):

View on GitHub (pinned to 1b2de5e052)

Solutions

1. For each path in the error, verify whether the file should exist at that location.
2. If it was removed/moved, delete or fix the entry in the .gyp 'sources' list.
3. If it is a generated file, ensure the generator step runs before this check, or remove the flag for that build.
4. If paths are relative, correct them so they resolve under the build directory.

Example fix

// before
'sources': ['src/removed.cc', 'src/main.cc']
// after
'sources': ['src/main.cc']

import os
build_dir = '.'
for s in target_dict.get('sources', []):
    if '$' in s:
        continue
    if not os.path.exists(os.path.normpath(os.path.join(build_dir, s))):
        raise FileNotFoundError(f'missing source referenced by {target_dict.get("target_name")}: {s}')

def all_regular_sources_exist(target_dict: dict, build_dir: str) -> bool:
    import os
    for s in target_dict.get('sources', []):
        if '$' in s:
            continue
        if not os.path.exists(os.path.normpath(os.path.join(build_dir, s))):
            return False
    return True

When it happens

Trigger: msvs_error_on_missing_sources is truthy in generator_flags and at least one entry in the target's sources resolves (after gyp_to_ninja and build_dir join) to a path that os.path.exists reports as missing.

Common situations: A source file was deleted or moved but not removed from the .gyp file; a generated source listed as a regular source but not yet produced; wrong relative path in sources; building before running a codegen step that creates the file.

Related errors

• AddFileConfig: file "%s" not in project.
• expected string; got %r
• expected string list; got %r
• expected bool; got %r
• index value (%d) not in expected range [0, %d)

AI-assisted analysis of nodejs/node@1b2de5e052 (2026-08-13). Data as JSON: /api/errors/33dae54d85edee5e. Report an issue: GitHub.