VM crash: stdin.hasTerminal on closed stdin on Windows

[davidmorgan]

VM crash: stdin.hasTerminal on closed stdin on Windows.

Repros on 3.9.3 and on 3.10.0-227.0.dev.

// parent.dart
import 'dart:io';
import 'dart:convert';

void main() async {
  final process = await Process.start('dart', ['child.dart']);
  process.stdin.close();
  process.stderr.transform(utf8.decoder).listen((string) {
    stderr.write(string);
  });
}

// child.dart
import 'dart:io';

void main() async {
  await stdin.drain();
  print(stdin.hasTerminal);
}

> dart --version
Dart SDK version: 3.9.3 (stable) (Tue Sep 9 12:02:51 2025 -0700) on "windows_x64"
> dart parent.dart

===== CRASH =====
ExceptionCode=-1073741819, ExceptionFlags=0, ExceptionAddress=00007FF6065113C4
version=3.9.3 (stable) (Tue Sep 9 12:02:51 2025 -0700) on "windows_x64"
pid=43244, thread=14908, isolate_group=main(000002E46494BC80), isolate=main(000002E464965250)
os=windows, arch=x64, comp=no, sim=no
isolate_instructions=7ff6064f9ae0, vm_instructions=7ff6064f9b00
fp=f64affe2d0, sp=f64affe180, pc=7ff6065113c4
  pc 0x00007ff6065113c4 fp 0x000000f64affe2d0 Dart_DetectNullSafety+0xf354
  pc 0x000002e466330fb1 fp 0x000000f64affe308 Unknown symbol
  pc 0x000002e466330e4b fp 0x000000f64affe348 Unknown symbol
  pc 0x000002e466349b53 fp 0x000000f64affe380 Unknown symbol
  pc 0x000002e466349679 fp 0x000000f64affe3e8 Unknown symbol
  pc 0x000002e466348e56 fp 0x000000f64affe440 Unknown symbol
  pc 0x000002e46632c531 fp 0x000000f64affe478 Unknown symbol
  pc 0x000002e466348c99 fp 0x000000f64affe4c8 Unknown symbol
  pc 0x000002e466348b5c fp 0x000000f64affe520 Unknown symbol
  pc 0x000002e46634884d fp 0x000000f64affe570 Unknown symbol
  pc 0x000002e466348535 fp 0x000000f64affe5d0 Unknown symbol
  pc 0x000002e46634763d fp 0x000000f64affe650 Unknown symbol
  pc 0x000002e4663461eb fp 0x000000f64affe6a0 Unknown symbol
  pc 0x000002e466345e67 fp 0x000000f64affe6e8 Unknown symbol
  pc 0x000002e466345c9d fp 0x000000f64affe750 Unknown symbol
  pc 0x000002e466345888 fp 0x000000f64affe790 Unknown symbol
  pc 0x000002e466343bc4 fp 0x000000f64affe7e0 Unknown symbol
  pc 0x000002e466343812 fp 0x000000f64affe818 Unknown symbol
  pc 0x000002e46634360d fp 0x000000f64affe850 Unknown symbol
  pc 0x000002e466343416 fp 0x000000f64affe888 Unknown symbol
  pc 0x000002e466343124 fp 0x000000f64affe8c0 Unknown symbol
  pc 0x000002e466342dfb fp 0x000000f64affe908 Unknown symbol
  pc 0x000002e466342993 fp 0x000000f64affe948 Unknown symbol
  pc 0x000002e4663427de fp 0x000000f64affe9c8 Unknown symbol
  pc 0x000002e466342403 fp 0x000000f64affea20 Unknown symbol
  pc 0x000002e466341f94 fp 0x000000f64affea60 Unknown symbol
  pc 0x000002e466341d1c fp 0x000000f64affeaa0 Unknown symbol
  pc 0x000002e466341a1b fp 0x000000f64affeae0 Unknown symbol
  pc 0x000002e4663416aa fp 0x000000f64affeb20 Unknown symbol
  pc 0x000002e466341475 fp 0x000000f64affeb60 Unknown symbol
  pc 0x000002e46633ebe0 fp 0x000000f64affebb8 Unknown symbol
  pc 0x000002e46633e3b8 fp 0x000000f64affec00 Unknown symbol
  pc 0x000002e46633dfcf fp 0x000000f64affec40 Unknown symbol
  pc 0x000002e46633dee3 fp 0x000000f64affec68 Unknown symbol
  pc 0x000002e46633de05 fp 0x000000f64affeca8 Unknown symbol
  pc 0x000002e466329ab3 fp 0x000000f64affece8 Unknown symbol
  pc 0x000002e464f830df fp 0x000000f64affee10 Unknown symbol
-- End of DumpStackTrace
  pc 0x0000000000000000 fp 0x000000f64affe2d0 sp 0x0000000000000000 [Stub] CallAutoScopeNative
  pc 0x000002e466330fb1 fp 0x000000f64affe308 sp 0x000000f64affe2e0 [Unoptimized] _getSocketType@15069316
  pc 0x000002e466330e4b fp 0x000000f64affe348 sp 0x000000f64affe318 [Unoptimized] _StdIOUtils@15069316._nativeSocketType@15069316
  pc 0x000002e466349b53 fp 0x000000f64affe380 sp 0x000000f64affe358 [Unoptimized] _StdIOUtils@15069316._socketType@15069316
  pc 0x000002e466349679 fp 0x000000f64affe3e8 sp 0x000000f64affe390 [Unoptimized] stdioType
  pc 0x000002e466348e56 fp 0x000000f64affe440 sp 0x000000f64affe3f8 [Unoptimized] Stdin.get:hasTerminal
  pc 0x000002e46632c531 fp 0x000000f64affe478 sp 0x000000f64affe450 [Unoptimized] main
  pc 0x000002e466348c99 fp 0x000000f64affe4c8 sp 0x000000f64affe488 [Unoptimized] _SuspendState@5048458._createAsyncCallbacks@5048458.thenCallback
  pc 0x000002e466348b5c fp 0x000000f64affe520 sp 0x000000f64affe4d8 [Unoptimized] _RootZone@5048458.runUnary
  pc 0x000002e46634884d fp 0x000000f64affe570 sp 0x000000f64affe530 [Unoptimized] _FutureListener@5048458.handleValue
  pc 0x000002e466348535 fp 0x000000f64affe5d0 sp 0x000000f64affe580 [Unoptimized] _Future@5048458._propagateToListeners@5048458.handleValueCallback
  pc 0x000002e46634763d fp 0x000000f64affe650 sp 0x000000f64affe5e0 [Unoptimized] _Future@5048458._propagateToListeners@5048458
  pc 0x000002e4663461eb fp 0x000000f64affe6a0 sp 0x000000f64affe660 [Unoptimized] _Future@5048458._complete@5048458
  pc 0x000002e466345e67 fp 0x000000f64affe6e8 sp 0x000000f64affe6b0 [Unoptimized] _BufferingStreamSubscription@5048458.asFuture.<anonymous closure>
  pc 0x000002e466345c9d fp 0x000000f64affe750 sp 0x000000f64affe6f8 [Unoptimized] _RootZone@5048458.runGuarded
  pc 0x000002e466345888 fp 0x000000f64affe790 sp 0x000000f64affe760 [Unoptimized] _BufferingStreamSubscription@5048458._sendDone@5048458.sendDone
  pc 0x000002e466343bc4 fp 0x000000f64affe7e0 sp 0x000000f64affe7a0 [Unoptimized] _BufferingStreamSubscription@5048458._sendDone@5048458
  pc 0x000002e466343812 fp 0x000000f64affe818 sp 0x000000f64affe7f0 [Unoptimized] _BufferingStreamSubscription@5048458._close@5048458
  pc 0x000002e46634360d fp 0x000000f64affe850 sp 0x000000f64affe828 [Unoptimized] _SyncStreamController@5048458._sendDone@5048458
  pc 0x000002e466343416 fp 0x000000f64affe888 sp 0x000000f64affe860 [Unoptimized] _StreamController@5048458._closeUnchecked@5048458
  pc 0x000002e466343124 fp 0x000000f64affe8c0 sp 0x000000f64affe898 [Unoptimized] _StreamController@5048458.close
  pc 0x000002e466342dfb fp 0x000000f64affe908 sp 0x000000f64affe8d0 [Unoptimized] _Socket@15069316._onData@15069316
  pc 0x000002e466342993 fp 0x000000f64affe948 sp 0x000000f64affe918 [Unoptimized] _Socket@15069316._onData@15069316
  pc 0x000002e4663427de fp 0x000000f64affe9c8 sp 0x000000f64affe958 [Unoptimized] _RootZone@5048458.runUnaryGuarded
  pc 0x000002e466342403 fp 0x000000f64affea20 sp 0x000000f64affe9d8 [Unoptimized] _BufferingStreamSubscription@5048458._sendData@5048458
  pc 0x000002e466341f94 fp 0x000000f64affea60 sp 0x000000f64affea30 [Unoptimized] _BufferingStreamSubscription@5048458._add@5048458
  pc 0x000002e466341d1c fp 0x000000f64affeaa0 sp 0x000000f64affea70 [Unoptimized] _SyncStreamController@5048458._sendData@5048458
  pc 0x000002e466341a1b fp 0x000000f64affeae0 sp 0x000000f64affeab0 [Unoptimized] _StreamController@5048458._add@5048458
  pc 0x000002e4663416aa fp 0x000000f64affeb20 sp 0x000000f64affeaf0 [Unoptimized] _StreamController@5048458.add
  pc 0x000002e466341475 fp 0x000000f64affeb60 sp 0x000000f64affeb30 [Unoptimized] new _RawSocket@15069316..<anonymous closure>
  pc 0x000002e46633ebe0 fp 0x000000f64affebb8 sp 0x000000f64affeb70 [Unoptimized] _NativeSocket@15069316.issueReadEvent.issue
  pc 0x000002e46633e3b8 fp 0x000000f64affec00 sp 0x000000f64affebc8 [Unoptimized] _microtaskLoop@5048458
  pc 0x000002e46633dfcf fp 0x000000f64affec40 sp 0x000000f64affec10 [Unoptimized] _startMicrotaskLoop@5048458
  pc 0x000002e46633dee3 fp 0x000000f64affec68 sp 0x000000f64affec50 [Unoptimized] _startMicrotaskLoop@5048458
  pc 0x000002e46633de05 fp 0x000000f64affeca8 sp 0x000000f64affec78 [Unoptimized] _runPendingImmediateCallback@1026248
  pc 0x000002e466329ab3 fp 0x000000f64affece8 sp 0x000000f64affecb8 [Unoptimized] _RawReceivePort@1026248._handleMessage@1026248
  pc 0x000002e464f830df fp 0x000000f64affee10 sp 0x000000f64affecf8 [Stub] InvokeDartCode

[davidmorgan]

Found a simpler repro: it's about the stdin subscription in the child being closed, not the close from the parent.

So it can be done in one script.

// crash.dart
import 'dart:io';

void main() async {
  stdin.listen((_) {}).cancel();
  stdin.hasTerminal;
}

[ykmnkmi]

Same error without closing:

import 'dart:io';

void main() async {
  stdin.listen((_) {}).cancel();
  print(stdioType(stdin));
}

Dart SDK version: 3.9.2 (stable) (Wed Aug 27 03:49:40 2025 -0700) on "windows_x64"

[davidmorgan]

Thanks :)