assert Iterables.getOnlyElement(rootClassCompilationUnits) != null : "The build should have been aborted before this point if there is no root class compilation unit.";
IDefinition rootClassDefinition = rootClassRef.resolve(project);
if (rootClassDefinition == null)
return ImmutableList.<ICompilerProblem>of(new UnableToFindRootClassDefinitionProblem(targetSettings.getRootClassName()));
return ImmutableList.<ICompilerProblem>of();
}