An empty test.war with this will throw UnsupportedOperationException if a resource-root path is specified that does not exist.

<?xml version="1.0" encoding="UTF-8"?>
<jboss-deployment-structure xmlns="urn:jboss:deployment-structure:1.2">

<module name="deployment.example">
<resources>
<resource-root path="../../../../../../../../work/workspace/release/build/classes/main" />
</resources>
</module>
</jboss-deployment-structure>

Here is the exception:

11:56:53,819 WARN [org.jboss.as.server.deployment] (MSC service thread 1-7) JBAS015959: Additional resource root /work/workspace/release/build/classes/main added via jboss-deployment-structure.xml does not exist
11:56:53,821 ERROR [org.jboss.msc.service.fail] (MSC service thread 1-7) MSC00001: Failed to start service jboss.deployment.unit."test.war".STRUCTURE: org.jboss.msc.service.StartException in service jboss.deployment.unit."test.war".STRUCTURE: JBAS018733: Failed to process phase STRUCTURE of deployment "test.war"
at org.jboss.as.server.deployment.DeploymentUnitPhaseService.start(DeploymentUnitPhaseService.java:126) [jboss-as-server-7.2.0.Alpha1-SNAPSHOT.jar:7.2.0.Alpha1-SNAPSHOT]
at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1811) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1746) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) [rt.jar:1.6.0_21]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) [rt.jar:1.6.0_21]
at java.lang.Thread.run(Thread.java:619) [rt.jar:1.6.0_21]
Caused by: java.lang.UnsupportedOperationException
at java.util.Collections$UnmodifiableList$1.remove(Collections.java:1183) [rt.jar:1.6.0_21]
at org.jboss.as.server.deployment.module.descriptor.DeploymentStructureDescriptorParser.deploy(DeploymentStructureDescriptorParser.java:201) [jboss-as-server-7.2.0.Alpha1-SNAPSHOT.jar:7.2.0.Alpha1-SNAPSHOT]
at org.jboss.as.server.deployment.DeploymentUnitPhaseService.start(DeploymentUnitPhaseService.java:119) [jboss-as-server-7.2.0.Alpha1-SNAPSHOT.jar:7.2.0.Alpha1-SNAPSHOT]
... 5 more

The issue looks like:
org.jboss.as.server.deployment.module.descriptor.DeploymentStructureDescriptorParser itr.remove() is called, but the additionalModule.getResourceRoots is returning the list as Collections.unmodifiableList.

It looks like if a <deployment> lists resource roots that do not exist, it just logs a warning. So I think the fix is to remove the Collections.unmodifiableList from ModuleStructureSpec, but I'm not sure if there was a reason unmodifiableList was added.

final ListIterator<ResourceRoot> itr = additionalModule.getResourceRoots().listIterator();
while (itr.hasNext()) {
final ResourceRoot resourceRoot = itr.next();
if(!resourceRoot.getRoot().exists())

{ ServerLogger.DEPLOYMENT_LOGGER.additionalResourceRootDoesNotExist(resourceRoot.getRoot().getPathName()); itr.remove(); }

}

org.jboss.as.server.deployment.module.descriptor.ModuleStructureSpec

class ModuleStructureSpec {

private final List<ResourceRoot> resourceRoots = new ArrayList<ResourceRoot>();

public List<ResourceRoot> getResourceRoots()

{ return Collections.unmodifiableList(resourceRoots); }