[ffi] Async sample crashes on Windows precompiled

[dcharkes]

Test crashes on Windows in precompiled mode, but runs fine in JIT mode.

https://dart-review.googlesource.com/c/sdk/+/134704

C:\src\dart-sdk\sdk>python tools/test.py -n dartk-win-debug-x64 samples/ffi/async/async_test -v -k
Test configuration:
    dartk-win-debug-x64(architecture: x64, compiler: dartk, mode: debug, runtime: vm, system: win)
Suites tested: samples
Running "vm" command: set DART_CONFIGURATION=DebugX64 & set DART_SUPPRESS_WER=1 & out\DebugX64\dart.exe --ignore-unrecognized-flags --packages=C:\src\dart-sdk\sdk\.packages C:\src\dart-sdk\sdk\samples\ffi\async\async_test.dart
Done dartk-vm debug_x64 samples/ffi/async/async_test: pass
C:\src\dart-sdk\sdk>python tools/test.py -n dartkp-win-debug-x64 samples/ffi/async/async_test -v -k
Test configuration:
    dartkp-win-debug-x64(architecture: x64, compiler: dartkp, mode: debug, runtime: dart_precompiled, system: win, vm-options: [--no-enable-malloc-hooks])
Suites tested: samples
Running "vm_compile_to_kernel []" command: set DART_CONFIGURATION=DebugX64 & set DART_SUPPRESS_WER=1 & C:\src\dart-sdk\sdk\pkg\vm\tool\gen_kernel.bat --aot --platform=out/DebugX64/vm_platform_strong.dill -o C:\src\dart-sdk\sdk\out\DebugX64\generated_compilations\dartkp\samples_ffi_async_async_test\out.dill C:\src\dart-sdk\sdk\samples\ffi\async\async_test.dart --packages=C:\src\dart-sdk\sdk\.packages -Ddart.developer.causal_async_stacks=true
Running "precompiler" command: set DART_CONFIGURATION=DebugX64 & set DART_SUPPRESS_WER=1 & out\DebugX64\gen_snapshot --snapshot-kind=app-aot-elf --elf=C:/src/dart-sdk/sdk/out/DebugX64/generated_compilations/dartkp/samples_ffi_async_async_test/out.aotsnapshot --no-enable-malloc-hooks --ignore-unrecognized-flags --packages=C:\src\dart-sdk\sdk\.packages C:\src\dart-sdk\sdk\out\DebugX64\generated_compilations\dartkp\samples_ffi_async_async_test\out.dill
Running "vm" command: set DART_CONFIGURATION=DebugX64 & set DART_SUPPRESS_WER=1 & out\DebugX64\dart_precompiled_runtime.exe --no-enable-malloc-hooks --ignore-unrecognized-flags --packages=C:\src\dart-sdk\sdk\.packages C:/src/dart-sdk/sdk/out/DebugX64/generated_compilations/dartkp/samples_ffi_async_async_test/out.aotsnapshot

FAILED: dartkp-dart_precompiled debug_x64 samples/ffi/async/async_test
Expected: Pass
Actual: Crash

--- Command "vm_compile_to_kernel []" (took 14.000224s):
set DART_CONFIGURATION=DebugX64 & set DART_SUPPRESS_WER=1 & C:\src\dart-sdk\sdk\pkg\vm\tool\gen_kernel.bat --aot --platform=out/DebugX64/vm_platform_strong.dill -o C:\src\dart-sdk\sdk\out\DebugX64\generated_compilations\dartkp\samples_ffi_async_async_test\out.dill C:\src\dart-sdk\sdk\samples\ffi\async\async_test.dart --packages=C:\src\dart-sdk\sdk\.packages -Ddart.developer.causal_async_stacks=true

exit code:
0

--- Command "precompiler" (took 11.000273s):
set DART_CONFIGURATION=DebugX64 & set DART_SUPPRESS_WER=1 & out\DebugX64\gen_snapshot --snapshot-kind=app-aot-elf --elf=C:/src/dart-sdk/sdk/out/DebugX64/generated_compilations/dartkp/samples_ffi_async_async_test/out.aotsnapshot --no-enable-malloc-hooks --ignore-unrecognized-flags --packages=C:\src\dart-sdk\sdk\.packages C:\src\dart-sdk\sdk\out\DebugX64\generated_compilations\dartkp\samples_ffi_async_async_test\out.dill

exit code:
0

--- Command "vm" (took 307ms):
set DART_CONFIGURATION=DebugX64 & set DART_SUPPRESS_WER=1 & out\DebugX64\dart_precompiled_runtime.exe --no-enable-malloc-hooks --ignore-unrecognized-flags --packages=C:\src\dart-sdk\sdk\.packages C:/src/dart-sdk/sdk/out/DebugX64/generated_compilations/dartkp/samples_ffi_async_async_test/out.aotsnapshot

exit code:
3

stdout:
a
b
yielding
Starting SimulateWork.
Starting worker threads.
Work1 Start.
Work2 Start.
Posting message (send_port: e9adb7343b907, work_address: 30efa60).
Started SimulateWork.

stderr:
===== CRASH =====
ExceptionCode=-1073741819, ExceptionFlags=0, ExceptionAddress=00000000015510F6
version=2.8.0-edge.76e7065ad5aaa2fe3010e9d767b964c0e86793d5 (Mon Feb 10 16:04:55 2020 +0100) on "windows_x64"
thread=14320, isolate=(null)(0000000000000000)
isolate_instructions=0, vm_instructions=21f2000
Stack dump aborted because InitialRegisterCheck failed.

From VS debugger:

Exception thrown at 0x00000000015510F6 in dart_precompiled_runtime.exe: 0xC0000005: Access violation executing location 0x00000000015510F6.

0000000004C86C41 call qword ptr [__imp_EnterCriticalSection (0538F4F0h)]

 	00000000015510f6()	Unknown
>	dart.exe!__acrt_lock(__acrt_lock_id _Lock) Line 55	C++
 	dart.exe!_realloc_dbg(void * block, unsigned __int64 requested_size, int block_use, const char * file_name, int line_number) Line 754	C++
 	dart.exe!realloc(void * block, unsigned __int64 size) Line 41	C++
 	[Inline Frame] dart.exe!dart::WriteStream::{ctor}(unsigned char * *) Line 324	C++
 	[Inline Frame] dart.exe!dart::BaseWriter::{ctor}(unsigned char *(*)(unsigned char *, __int64, __int64)) Line 542	C++
 	dart.exe!dart::ApiMessageWriter::ApiMessageWriter() Line 777	C++
 	dart.exe!dart::PostCObjectHelper(__int64 port_id, _Dart_CObject * message) Line 47	C++
 	ffi_test_functions.dll!dart::NotifyDart(__int64 send_port, const std::function<void __cdecl(void)> * work) Line 306	C++
 	ffi_test_functions.dll!dart::doCallback2(__int64 a) Line 339	C++
 	ffi_test_functions.dll!dart::Work2() Line 363	C++
 	[Inline Frame] ffi_test_functions.dll!std::_Invoker_functor::_Call(void(*)() &&) Line 230	C++
 	[Inline Frame] ffi_test_functions.dll!std::invoke(void(*)() &&) Line 230	C++
 	[Inline Frame] ffi_test_functions.dll!std::_LaunchPad<std::unique_ptr<std::tuple<void (__cdecl*)(void)>,std::default_delete<std::tuple<void (__cdecl*)(void)> > > >::_Execute(std::tuple<void (__cdecl*)(void)> &) Line 238	C++
 	[Inline Frame] ffi_test_functions.dll!std::_LaunchPad<std::unique_ptr<std::tuple<void (__cdecl*)(void)>,std::default_delete<std::tuple<void (__cdecl*)(void)> > > >::_Run(std::_LaunchPad<std::unique_ptr<std::tuple<void (__cdecl*)(void)>,std::default_delete<std::tuple<void (__cdecl*)(void)> > > > *) Line 245	C++
 	ffi_test_functions.dll!std::_LaunchPad<std::unique_ptr<std::tuple<void (__cdecl*)(void)>,std::default_delete<std::tuple<void (__cdecl*)(void)> > > >::_Go() Line 230	C++
 	ffi_test_functions.dll!std::_Pad::_Call_func(void * _Data) Line 209	C++
 	ffi_test_functions.dll!thread_start<unsigned int (__cdecl*)(void *),1>(void * const parameter) Line 97	C++
 	kernel32.dll!BaseThreadInitThunk�()	Unknown
 	ntdll.dll!RtlUserThreadStart�()	Unknown

cc @mkustermann

The alloc that is used:

static uint8_t* malloc_allocator(uint8_t* ptr,
                                 intptr_t old_size,
                                 intptr_t new_size) {
  void* new_ptr = realloc(reinterpret_cast<void*>(ptr), new_size);
  return reinterpret_cast<uint8_t*>(new_ptr);
}

N.b. it also fails in Release mode.

If memblock is NULL, realloc behaves the same way as malloc and allocates a new block of size bytes.

	block	0x0000000000000000	void * const
	size	0x0000000000000200	const unsigned __int64

runtime\vm\datastream.h:324

   *buffer_ = reinterpret_cast<uint8_t*>(alloc_(NULL, 0, initial_size_));

Debugger is at some locking step.

--- minkernel\crts\ucrt\src\appcrt\internal\locks.cpp --------------------------
void __cdecl __vcrt_lock(_In_ __vcrt_lock_id _Lock)
{
    EnterCriticalSection(&__vcrt_lock_table[_Lock]);
0000000004C86C20  mov         dword ptr [rsp+8],ecx  
0000000004C86C24  sub         rsp,28h  
}
0000000004C86C28  movsxd      rax,dword ptr [_Lock]  
0000000004C86C2D  imul        rax,rax,28h  
0000000004C86C31  lea         rcx,[__acrt_lock_table (052BCEA0h)]  
0000000004C86C38  add         rcx,rax  
0000000004C86C3B  mov         rax,rcx  
0000000004C86C3E  mov         rcx,rax  
0000000004C86C41  call        qword ptr [__imp_EnterCriticalSection (0538F4F0h)]  
^^^^^^^^^^^
0000000004C86C47  add         rsp,28h  
0000000004C86C4B  ret  

[dcharkes]

Update, it's trying to use dart.exe symbols, instead of dart_precompiled_runtime.exe symbols in AOT. That's why it works in JIT but not in AOT.

Changing the way we build the dll makes it work in AOT, but not in JIT:

shared_library("ffi_test_functions") {
  deps = [
    ":dart",
  ]

  # The two files here do not depend on each other.
  # flutter/flutter integration tests will only use `ffi_test_functions.cc` -
  # any test functionality using `dart_api.h` has to go into
  # `ffi_test_functions_vmspecific.cc`.
  sources = [
    "ffi_test/ffi_test_functions.cc",
    "ffi_test/ffi_test_functions_vmspecific.cc",
  ]
  if (is_win && current_cpu == "x64") {
    sources += [ "ffi_test/clobber_x64_win.S" ]
  } else if (!is_win) {
    sources += [ "ffi_test/clobber_$current_cpu.S" ]
  }
  include_dirs = [ ".." ]
  defines = [
    # The only effect of DART_SHARED_LIB is to export the Dart API.
    "DART_SHARED_LIB",
  ]
  if (is_linux || is_android) {
    cflags = [ "-fPIC" ]
  }
  if (is_win) {
    libs = [ "dart_precompiled_runtime.lib" ] # changed this one
    abs_root_out_dir = rebase_path(root_out_dir)
    ldflags = [ "/LIBPATH:$abs_root_out_dir" ]
  }
}

[dcharkes]

I filed an issue for the root cause: #40579.