Bug 25581 - xbuild crashes due to NullReferenceException when removing items from ItemGroup (bugjar included)
Summary: xbuild crashes due to NullReferenceException when removing items from ItemGro...
Status: NEW
Alias: None
Product: Tools
Classification: Mono
Component: xbuild ()
Version: unspecified
Hardware: PC Linux
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2014-12-22 16:54 UTC by Roger Twede
Modified: 2015-01-05 15:12 UTC (History)
2 users (show)

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

Project file that when built demonstrates the xbuild crash (999 bytes, application/octet-stream)
2014-12-22 16:54 UTC, Roger Twede

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Description Roger Twede 2014-12-22 16:54:20 UTC
Created attachment 9170 [details]
Project file that when built demonstrates the xbuild crash

XBuild/Mono Release Version 3.10.0  (among others)

A project file bugjar.proj is attached.  Building the project file will cause the crash.

When Items are removed from an ItemGroup and then re-added, it is no longer possible to remove them without crashing xbuild.  The collection maintenance appears to have a defect that doesn't maintain the group's clean/good state after the initial remove since re-adding items will result in a different state than the initial adding of the items.

Stack back-trace:

Error building target Setup: System.NullReferenceException: Object reference not set to an instance of an object
  at Microsoft.Build.BuildEngine.BuildItem.InsertElementAfter (Microsoft.Build.BuildEngine.BuildItem parent, Microsoft.Build.BuildEngine.BuildItem child, System.Xml.XmlElement insertAfter) [0x00000] in <filename unknown>:0
  at Microsoft.Build.BuildEngine.BuildItem.SplitParentItem () [0x00000] in <filename unknown>:0
  at Microsoft.Build.BuildEngine.BuildItem.Detach () [0x00000] in <filename unknown>:0
  at Microsoft.Build.BuildEngine.BuildItemGroup.RemoveItem (ITaskItem itemToRemove) [0x00000] in <filename unknown>:0
  at Microsoft.Build.BuildEngine.BuildItem.RemoveItems (Microsoft.Build.BuildEngine.Project project) [0x00000] in <filename unknown>:0
  at Microsoft.Build.BuildEngine.BuildItem.Evaluate (Microsoft.Build.BuildEngine.Project project, Boolean evaluatedTo) [0x00000] in <filename unknown>:0
  at Microsoft.Build.BuildEngine.BuildTaskItem.Execute () [0x00000] in <filename unknown>:0
  at Microsoft.Build.BuildEngine.TaskBatchingImpl.Execute (IBuildTask buildTask, TaskExecutionMode taskExecutionMode) [0x00000] in <filename unknown>:0
  at Microsoft.Build.BuildEngine.TaskBatchingImpl.Build (IBuildTask buildTask, TaskExecutionMode taskExecutionMode, System.Boolean& executeOnErrors) [0x00000] in <filename unknown>:0
  at Microsoft.Build.BuildEngine.TargetBatchingImpl.RunTargetWithBucket (System.Collections.Generic.Dictionary`2 bucket, Microsoft.Build.BuildEngine.Target target, System.Boolean& executeOnErrors) [0x00000] in <filename unknown>:0
  at Microsoft.Build.BuildEngine.TargetBatchingImpl.Run (Microsoft.Build.BuildEngine.Target target, System.Boolean& executeOnErrors) [0x00000] in <filename unknown>:0
  at Microsoft.Build.BuildEngine.TargetBatchingImpl.Build (Microsoft.Build.BuildEngine.Target target, System.Boolean& executeOnErrors) [0x00000] in <filename unknown>:0
  at Microsoft.Build.BuildEngine.Target.DoBuild (System.Boolean& executeOnErrors) [0x00000] in <filename unknown>:0