Bug 45200 - Marshal.PtrToStructure struct with byte array fails with null reference exception
Summary: Marshal.PtrToStructure struct with byte array fails with null reference excep...
Alias: None
Product: Android
Classification: Xamarin
Component: Mono runtime / AOT Compiler ()
Version: unspecified
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Marek Habersack
Depends on:
Reported: 2016-10-07 18:16 UTC by John Miller [MSFT]
Modified: 2016-10-10 14:20 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

Sample Project (35.34 KB, application/zip)
2016-10-07 18:16 UTC, John Miller [MSFT]

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Description John Miller [MSFT] 2016-10-07 18:16:16 UTC
Created attachment 17938 [details]
Sample Project


Marshal.PtrToStructure produces a NRE when a struct has a byte[]. The same code works in a console application on Windows/Mac.

**Steps to Reproduce**:

1. Run the attached android project and press the button for the Error. 

**Actual Results**:

Object reference not set to an instance of an object
  at (wrapper unknown) MarshalException.MyStructs+Struct01:PtrToStructure (intptr,object)
  at (wrapper managed-to-native) System.Runtime.InteropServices.Marshal:PtrToStruc...

**Expected Results**:

No exception. See the console application in the solution to test without Android.

**Build Date & Platform**:

Microsoft Visual Studio Enterprise 2015
Version 14.0.25431.01 Update 3
Microsoft .NET Framework
Version 4.6.01586

Installed Version: Enterprise

Architecture and Modeling Tools   00322-80000-00000-AA000
Microsoft Architecture and Modeling Tools
UML® and Unified Modeling Language™ are trademarks or registered trademarks of the Object Management Group, Inc. in the United States and other countries.

Visual Basic 2015   00322-80000-00000-AA000
Microsoft Visual Basic 2015

Visual C# 2015   00322-80000-00000-AA000
Microsoft Visual C# 2015

Visual C++ 2015   00322-80000-00000-AA000
Microsoft Visual C++ 2015

Windows Phone SDK 8.0 - ENU   00322-80000-00000-AA000
Windows Phone SDK 8.0 - ENU

ASP.NET and Web Tools 2015.1   14.1.20907.0
ASP.NET and Web Tools 2015.1

ASP.NET Web Frameworks and Tools 2012.2   4.1.41102.0
For additional information, visit http://go.microsoft.com/fwlink/?LinkID=309563

ASP.NET Web Frameworks and Tools 2013   5.2.40314.0
For additional information, visit http://www.asp.net/

Azure App Service Tools v2.8.1   14.0.11123.0
Azure App Service Tools v2.8.1

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JavaScript Language Service   2.0
JavaScript Language Service

JavaScript Project System   2.0
JavaScript Project System

Microsoft .NET Core Tools (Preview 2)   14.1.20907.0
Microsoft .NET Core Tools (Preview 2)

Microsoft Azure Mobile Services Tools   1.4
Microsoft Azure Mobile Services Tools

NuGet Package Manager   3.5.0
NuGet Package Manager in Visual Studio. For more information about NuGet, visit http://docs.nuget.org/.

PreEmptive Analytics Visualizer   1.2
Microsoft Visual Studio extension to visualize aggregated summaries from the PreEmptive Analytics product.

SQL Server Data Tools   14.0.60519.0
Microsoft SQL Server Data Tools

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Visual Studio extension to enable development for Xamarin.iOS.
Comment 2 Marek Habersack 2016-10-10 11:30:54 UTC
The error no longer occurs with the current XA/master (to be released in Cycle 9). You can test the latest XA/master on Mac using this build: https://bosstoragemirror.blob.core.windows.net/wrench/monodroid-mavericks-master/cf/cf2beeaf61722a06763b2935ca84a81365c8e6b7/xamarin.android-7.0.99-121.pkg
Comment 3 Isabele Leal 2016-10-10 14:07:47 UTC
Do you have a prevision when the Cycle 9 will be release to PC Windows?
Comment 4 Marek Habersack 2016-10-10 14:20:58 UTC
Hopefully in 3-5 weeks.