This is a fatal error, there's no way to recover from it, and in release builds, a nasty message box appears. It happens when I call serial_port::cancel and Boost tries to throw some exception. The exact error is:

Run-Time Check Failure #0 - The value of ESP was not properly saved across a function call.  This is usually a result of calling a function declared with one calling convention with a function pointer declared with a different calling convention.

And it seems to happen in throw_error.ipp, inside the do_throw_error method.
Here's a small sample program which reproduces this:

#include <boost/asio/serial_port.hpp>
#include <boost/asio/read.hpp>
#include <boost/thread.hpp>
#include <iostream>

using namespace std;

BYTE g_pBuffer[128];

void ReadCompletionHandler( boost::system::error_code ec, std::size_t bytesTransferred ){
if( !ec ){
cout << "Read " << bytesTransferred << " bytes successfully" << endl;
}else if( ec == boost::asio::error::operation_aborted ){
cout << "Aborted async_read_some, " << bytesTransferred << " bytes transferred" << endl;
}else{
cout << "Read finished with errors: " << ec.message() << endl;
}
}

void ReaderThread( boost::asio::serial_port* pSerialPort ){
cout << "[ReaderThread] Started reading" << endl;
boost::asio::async_read( *pSerialPort, boost::asio::buffer( g_pBuffer, 5 ), ReadCompletionHandler );
cout << "[ReaderThread] Done!" << endl;
}

void main(){
//Tell cout not to buffer its output so output better reflects multithreaded execution
std::cout.setf(std::ios::unitbuf);
boost::asio::io_service ioService;
boost::asio::serial_port serialPort( ioService );
string portName = "COM1";
serialPort.open( portName );
if( !serialPort.is_open() ){
cout << "Failed to open " << portName << endl;
return;
}
cout << "Launching reader thread and io_service" << endl;
boost::thread readerThread( boost::bind( ReaderThread, &serialPort ) );
ioService.run();
cout << "Sleeping..." << endl;
::Sleep( 5000 );
cout << "Woke up, cancelling pending reads" << endl;
serialPort.cancel();
cout << "Waiting for reader thread to finish..." << endl;
readerThread.join();
cout << "Done!" << endl;
cin.get();
}

Maybe I'm doing something stupid. What do you think?

--

Darío Eduardo Ramos
Meditech S.A. www.meditech.com.ar
(+54) 01147603300, Interno 31

Av. Julio A. Roca 3456

Florida Oeste, Bs.As. Argentina