 
	
Syntactic errors in plugin.xml, fragment.xml and MANIFEST.MF are all flagged as errors by the plug-in manifest compiler. As for semantic problems in the plug-in manifests, the severity for each problem category can be set to Error, Warning or Ignore.
      The plug-in compiler preferences are set at a workspace level on the
      
       Window >
      Preferences... > Plug-in Development > Compilers
      preference page and take effect on all plug-in projects in the workspace.
    
It is also possible to override the workspace-scope settings by having compiler settings at the plug-in project level. To do so, select Properties from the context menu of a plug-in project. In the Properties dialog, project-level manifest compiler settings can be customized on the Plug-in Development > Plug-in Manifest Compiler preference page.
	 
	
| Option | Description | Default | 
|---|---|---|
| Required attributes not defined | A required attribute in a plug-in file is missing | Error | 
| Incompatible environment | The plug-in's environment settings do not match the target platform's environment settings | Warning | 
| Missing exported packages | One or more packages in a java source folder are not included in the Export-Package manifest entry | Ignore | 
| No automatic module name | Automatic-Module-Name header (required for Java 9 compatibility) is not present in MANIFEST.MF. For details, see this link. | Warning | 
	 
	
| Option | Description | Default | 
|---|---|---|
| Problems with 'source.<library>' entry | Semantic problem with source entry | Warning | 
| Problems with 'output.<library>' entry | Semantic problem with output entry | Warning | 
| Missing 'output.<library>' entry | A source entry exists without matching output | Ignore | 
| Problems with 'bin.includes' entry | Semantic problem with binary includes entry | Warning | 
| Problems with 'src.includes' entry | Semantic problem with source includes entry | Warning | 
| Missing or incompatible Java compliance properties | Project has Java compliance settings without matching entry in build.properties | Warning | 
| Missing project specific Java compiler settings | Project has Java complier settings without matching entry in build.properties | Ignore | 
| Missing or incorrect file encodings | Project has file encoding settings without matching entry in build.properties | Ignore | 
| Other problems with build.properties files | Other problems not part of another setting | Warning | 
	 
	
| Option | Description | Default | 
|---|---|---|
| Missing versions on required bundles | A required bundle manifest entry does not have version restrictions | Ignore | 
| Missing versions on exported packages | An exported package manifest entry does not have a version specified | Ignore | 
| Missing versions on imported packages | An imported package manifest entry does not have version restrictions | Ignore | 
| Bundle BREE lower than its dependencies | At least one of the bundle's dependencies requires an execution environment that is higher than the bundle's current execution environment | Warning | 
	 
	
| Option | Description | Default | 
|---|---|---|
| Unresolved dependencies | A plug-in dependency (required bundle or imported package) can not be found | Error | 
| Unresolved extension points | The provider for an extension point cannot be found | Error | 
| Usage of internal extension points | Providing an extension to an extension point that is marked as internal | Warning | 
| Usage of deprecated atributes and elements | Providing an extension that uses attributes or elements from an extension point that are marked as deprecated | Warning | 
| Usage of non-externalized strings | A plug-in is using a string that could be translated in plugin.properties | Ignore | 
| Usage of service component without lazy activation policy | Bundle manifest has a Service-Component without a Bundle-ActivationPolicy: lazy entry | Warning | 
	 
	
| Option | Description | Default | 
|---|---|---|
| Illegal elements | Referencing an illegal element in an extension | Warning | 
| Illegal atributes | Referencing an illegal attribute in an extension | Warning | 
| References to non-existent classes | Referencing a class from an extension that does not exist in the project | Warning | 
| References to discourage classes | Referencing a class from an extension that has discouraged access warnings | Warning | 
| References to non-existent resources | References a resource from an extension that does not exist in the project | Warning | 
| References to non-existent identifier attributes | Referencing an identifier attribute that is not defined by a known extension | Warning | 
The following is a brief explanation for some of the non-obvious potential problems that are flagged by PDE: