NPE in CModelManager.shutdown() - is this a known issue?

[pnipin]

Hi,

During Eclipse shutdown, I'm seeing a NullPointerException originating from CModelManager.shutdown() with a following stack trace:

org.osgi.framework.BundleException: Exception in org.eclipse.cdt.core.CCorePlugin.stop() of bundle org.eclipse.cdt.core.
	at org.eclipse.osgi.internal.framework.BundleContextImpl.stop(BundleContextImpl.java:928)
	at org.eclipse.osgi.internal.framework.EquinoxBundle.stopWorker0(EquinoxBundle.java:1096)
	at org.eclipse.osgi.internal.framework.EquinoxBundle$EquinoxModule.stopWorker(EquinoxBundle.java:399)
	at org.eclipse.osgi.container.Module.doStop(Module.java:699)
	at org.eclipse.osgi.container.Module.stop(Module.java:557)
	at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.decStartLevel(ModuleContainer.java:2153)
	at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.doContainerStartLevel(ModuleContainer.java:2022)
	at org.eclipse.osgi.container.SystemModule.stopWorker(SystemModule.java:281)
	at org.eclipse.osgi.internal.framework.EquinoxBundle$SystemBundle$EquinoxSystemModule.stopWorker(EquinoxBundle.java:225)
	at org.eclipse.osgi.container.Module.doStop(Module.java:699)
	at org.eclipse.osgi.container.Module.stop(Module.java:557)
	at org.eclipse.osgi.container.SystemModule.stop(SystemModule.java:212)
	at org.eclipse.osgi.internal.framework.EquinoxBundle$SystemBundle$EquinoxSystemModule$1.run(EquinoxBundle.java:244)
	at java.base/java.lang.Thread.run(Thread.java:1583)
Caused by: java.lang.NullPointerException: Cannot invoke "org.eclipse.core.runtime.content.IContentTypeManager.removeContentTypeChangeListener(org.eclipse.core.runtime.content.IContentTypeManager$IContentTypeChangeListener)" because the return value of "org.eclipse.core.runtime.Platform.getContentTypeManager()" is null
	at org.eclipse.cdt.internal.core.model.CModelManager.shutdown(CModelManager.java:1378)
	at org.eclipse.cdt.core.model.CoreModel.shutdown(CoreModel.java:1156)
	at org.eclipse.cdt.core.CCorePlugin.stop(CCorePlugin.java:375)
	at org.eclipse.osgi.internal.framework.BundleContextImpl$3.run(BundleContextImpl.java:908)
	at org.eclipse.osgi.internal.framework.BundleContextImpl$3.run(BundleContextImpl.java:1)
	at java.base/java.security.AccessController.doPrivileged(AccessController.java:571)
	at org.eclipse.osgi.internal.framework.BundleContextImpl.stop(BundleContextImpl.java:900)
	... 13 more
Root exception:
java.lang.NullPointerException: Cannot invoke "org.eclipse.core.runtime.content.IContentTypeManager.removeContentTypeChangeListener(org.eclipse.core.runtime.content.IContentTypeManager$IContentTypeChangeListener)" because the return value of "org.eclipse.core.runtime.Platform.getContentTypeManager()" is null
	at org.eclipse.cdt.internal.core.model.CModelManager.shutdown(CModelManager.java:1378)
	at org.eclipse.cdt.core.model.CoreModel.shutdown(CoreModel.java:1156)
	at org.eclipse.cdt.core.CCorePlugin.stop(CCorePlugin.java:375)
	at org.eclipse.osgi.internal.framework.BundleContextImpl$3.run(BundleContextImpl.java:908)
	at org.eclipse.osgi.internal.framework.BundleContextImpl$3.run(BundleContextImpl.java:1)
	at java.base/java.security.AccessController.doPrivileged(AccessController.java:571)
	at org.eclipse.osgi.internal.framework.BundleContextImpl.stop(BundleContextImpl.java:900)
	at org.eclipse.osgi.internal.framework.EquinoxBundle.stopWorker0(EquinoxBundle.java:1096)
	at org.eclipse.osgi.internal.framework.EquinoxBundle$EquinoxModule.stopWorker(EquinoxBundle.java:399)
	at org.eclipse.osgi.container.Module.doStop(Module.java:699)
	at org.eclipse.osgi.container.Module.stop(Module.java:557)
	at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.decStartLevel(ModuleContainer.java:2153)
	at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.doContainerStartLevel(ModuleContainer.java:2022)
	at org.eclipse.osgi.container.SystemModule.stopWorker(SystemModule.java:281)
	at org.eclipse.osgi.internal.framework.EquinoxBundle$SystemBundle$EquinoxSystemModule.stopWorker(EquinoxBundle.java:225)
	at org.eclipse.osgi.container.Module.doStop(Module.java:699)
	at org.eclipse.osgi.container.Module.stop(Module.java:557)
	at org.eclipse.osgi.container.SystemModule.stop(SystemModule.java:212)
	at org.eclipse.osgi.internal.framework.EquinoxBundle$SystemBundle$EquinoxSystemModule$1.run(EquinoxBundle.java:244)
	at java.base/java.lang.Thread.run(Thread.java:1583)

Line throwing NPE in shutdown() is:

Platform.getContentTypeManager().removeContentTypeChangeListener(this);

My understanding is that Platform.getContentTypeManager() can return null if the Platform's content type manager has already been stopped before CCorePlugin.stop() runs (shutdown ordering race condition). The fix would be a simple null guard:

IContentTypeManager ctm = Platform.getContentTypeManager();
if (ctm != null) {
ctm.removeContentTypeChangeListener(this);
}

Does the root cause analysis above is correct, or is there something I'm missing

Environment: Eclipse [2026-03], CDT [12.4]

[pnipin]

@jonahgraham

[ruspl-afed]

The fix would be a simple null guard

It may hide the original problem: IContentTypeManager has become an OSGi component and CModelManager still interacts with it in a static manner.

[pnipin]

Thank you. I am planning to add a null check in my local repository, as these exceptions always occur during application shutdown and making it hard to track other errors.