c# - "Overflow or underflow in the arithmetic operation" WPF specific issue

Question

My WPF test app (very simple, just one window) is using a 3rd party managed dll (say X.dll). This managed dll uses some unmanaged dll's . So lets say I write a small wpf app which just references X.dll. And in the window's constructor I access something inside X.dll (ie. in some namespace in X.dll). On doing this i dont catch any exception and it seems like things are going on as expected. But upon returning the control to .NET runtime, I get an exception in Application class's 'DispatcherUnhandledException' handler :

“Overflow or underflow in the arithmetic operation.” System.ArithmeticException was unhandled Message="Overflow or underflow in the arithmetic operation."
Source="PresentationFramework"
StackTrace:

System.Windows.Window.ValidateTopLeft(Double length)
System.Windows.Window.CoerceTop(DependencyObject d, Object value) System.Windows.DependencyObject.ProcessCoerceValue(DependencyProperty dp, PropertyMetadata metadata, EntryIndex& entryIndex, Int32& targetIndex, EffectiveValueEntry& newEntry, EffectiveValueEntry& oldEntry, Object& oldValue, Object baseValue, CoerceValueCallback coerceValueCallback, Boolean coerceWithDeferredReference, Boolean skipBaseValueChecks)
System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, OperationType operationType)
System.Windows.DependencyObject.CoerceValue(DependencyProperty dp) at System.Windows.Window.SetupInitialState(Double requestedTop, Double requestedLeft, Double requestedWidth, Double requestedHeight)
System.Windows.Window.CreateSourceWindowImpl() at System.Windows.Window.SafeCreateWindow() at System.Windows.Window.ShowHelper(Object booleanBox)
System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Boolean isSingleParameter)
System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Boolean isSingleParameter, Delegate catchHandler)

Some points:

• This only occurs in WPF app and not in winforms app.
• This does not get caught in a try-catch. only in Application's DispatcherUnhandledException
• This does not happen if I access X.dll's code inside the Window's 'Loaded' event, only happens in constructor.

Can anyone guess the problem ?

Thanks, Mishal

Answer 1

Following the link from @Mishhl the fix is

public class FloatingPointReset
{
    [DllImport("msvcr110.dll", CallingConvention = CallingConvention.Cdecl)]
    public static extern int _fpreset();


    public static void Action()
    {
        // Reset the Floating Point (When called from External Application there was an Overflow exception)
        _fpreset();
    }
}

It's caused by something in an included DLL resetting the FP into a state that isn't compatible with WPF/C#/Microsoft DLL's. Delphi/CPPB does this by default.

So in either the window constructor or App() constructor just do

FloatingPointReset.Action();

You may need to change the following to reference any version of msvcr###.dll

[DllImport("msvcr110.dll", CallingConvention = CallingConvention.Cdecl)]

e.g.

[DllImport("msvcr70.dll", CallingConvention = CallingConvention.Cdecl)]