C# async problem

seems to bubble straight up the call stack.

Does the stack trace not tell you where the error is occurring?

The stack trace would be great but as its not breaking on the error by the time you realise an exception is thrown, the call stack is for the handling code, not the faulting code.

I'm not clear what you mean.  Is the following roughly what is happening?
You have a try...catch block in foo.  In that try...catch block you call foo2, which calls foo3, which calls foo4 ..... which calls fooXXX and somewhere in that an exception is thrown.

No, no try/catch in my code - I want to see all my errors!
I run a async task-based pattern to execute a procedure (with no try/catch block in), the procedure faults, I'm hoping to see which line, but the fault is caught in the task-asnyc calling bit, with no record of which line in my code threw the exception.

Its as if the async task pattern has a try/catch block on everything inside it so you can't trace the fault.

>>No, no try/catch in my code - I want to see all my errors!

Oh dear.  The whole point of try....catch is to trap an error AND DISPLAY IT IF REQUIRED at a point where you can easily locate what is the faulting code.

I never use error handling for 'normal flow' in my code, just for unpredictable activities, like talking to the outside world, file I/O etc. Normal flow shouldn't throw errors, everything should be pre-empted by the logic.
That's a coding style I've been using for 20 years...but don't get me started on overuse of error handling code.
But that isn't germane to this issue really which is that the error handling in the Task/Async pattern in over-zealous and handling unhandled errors when I want to break there.
Toggling the Debug-Exceptions/CLR seems to be the only way I've found.

OK, I'll bow out to your expertise in writing error free code in that case.

When the error bubbles up, is there anything in the InnerException property?

I'll asked for this to be reopened.  That comment is not an answer.

is there anything in the InnerException property?

There doesn't seem to be any exception thrown in the asnyc task (CLR) code, it's just catching my exception and ignoring it.

I am having to toggle the Debug-Exceptions-Thow All CLR check box - which is a tedious workaround...

I can relate to having to flip back and forth through Debug->Exceptions.

As to your issue, have you read through the following yet?

http://msdn.microsoft.com/en-us/library/dd997415(v=vs.110).aspx

Shall we assume that the behavior you are witnessing is different than what this document proposes?

I think the phenomenon is the one described in the document, but that doesn't really help when debugging, in the sense that the document suggests:

var task1 = Task.Factory.StartNew(() =>
{
    throw new MyCustomException("I'm bad, but not too bad!");
});

try
{
    task1.Wait();
}
catch (AggregateException ae)
{
    // Assume we know what's going on with this particular exception. 
    // Rethrow anything else. AggregateException.Handle provides 
    // another way to express this. See later example. 
    foreach (var e in ae.InnerExceptions)
    {
        if (e is MyCustomException)
        {
            Console.WriteLine(e.Message);
        }
        else
        {
            throw;
        }
    }

}

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whereas, for debug you want the code to actually break on the error, not a fancy-pants aggregated exception handler in the calling code.
I'm sure the old async patterns allowed you to break on exceptions without having to toggle the 'break on All exceptions' box. I suppose I could make a macro, but I think the VS macro recorder's been removed.

Aaahhhh, yes that's very interesting. Thanks for that. I'll have a play around.