Get "Attempted to read or write protected memory" Exception from generated DLL imported in C#

I created a C-shared library DLL and this DLL is imported in C# Here is the sample code:

        [DllImport(@"libmx.dll", CallingConvention = CallingConvention.Cdecl)]
        private static unsafe extern IntPtr mxCreateDoubleScalar([In]double value);
        [DllImport(@"CSharedLib.dll", ExactSpelling = true, CallingConvention = CallingConvention.Cdecl, SetLastError = false, CharSet = CharSet.Auto, EntryPoint = @"CSharedLibInitialize")]
        private static unsafe extern void CSharedLibInitialize();

        [DllImport(@"CSharedLib.dll", ExactSpelling = true, CallingConvention = CallingConvention.Cdecl, SetLastError = false, CharSet = CharSet.Auto)]
        private static unsafe extern void mlfChi2cdf([In]Int32 nargout, ref IntPtr output, [In]IntPtr number1, [In]IntPtr number2); 

        IntPtr iValue = IntPtr.Zero;
        CSharedLibInitialize();
        IntPtr pointer1 = mxCreateDoubleScalar(1);
        IntPtr pointer2 = mxCreateDoubleScalar(1);
        IntPtr output = IntPtr.Zero;
        mlfChi2cdf(1, ref output, pointer1, pointer2);

When I run into mlfChi2cdf, it throws out the AccessViolationException was thrown, "Attempted to read or write protected memory. This is often an indication that other memory is corrupt."

Any idea? I think I follow the standard way to use the generated DLL

Answer 1

[Preetha Joy]

I also had the same error. Could you manage to find the solution ?