diff --git a/java/compiler/impl/src/com/intellij/compiler/impl/CompileContextImpl.java b/java/compiler/impl/src/com/intellij/compiler/impl/CompileContextImpl.java
index cc353207e1a7..db182d31725f 100644
--- a/java/compiler/impl/src/com/intellij/compiler/impl/CompileContextImpl.java
+++ b/java/compiler/impl/src/com/intellij/compiler/impl/CompileContextImpl.java
@@ -142,7 +142,7 @@ public class CompileContextImpl extends UserDataHolderBase implements CompileCon
     final Module module = getModuleByFile(file);
     if (module != null) {
       final String procGenRoot = CompilerPaths.getAnnotationProcessorsGenerationPath(module);
-      if (VfsUtil.isAncestor(new File(procGenRoot), new File(file.getPath()), true)) {
+      if (procGenRoot != null && VfsUtil.isAncestor(new File(procGenRoot), new File(file.getPath()), true)) {
         return true;
       }
     }
diff --git a/java/compiler/impl/src/com/intellij/compiler/impl/javaCompiler/AnnotationProcessingCompiler.java b/java/compiler/impl/src/com/intellij/compiler/impl/javaCompiler/AnnotationProcessingCompiler.java
index 0a381533fc76..f93c1e191aa6 100644
--- a/java/compiler/impl/src/com/intellij/compiler/impl/javaCompiler/AnnotationProcessingCompiler.java
+++ b/java/compiler/impl/src/com/intellij/compiler/impl/javaCompiler/AnnotationProcessingCompiler.java
@@ -116,8 +116,8 @@ public class AnnotationProcessingCompiler implements TranslatingCompiler{
         return true;
       }
       final String path = CompilerPaths.getAnnotationProcessorsGenerationPath(module);
-      final VirtualFile generationDir = LocalFileSystem.getInstance().findFileByPath(path);
-      if (VfsUtil.isAncestor(generationDir, file, false)) {
+      final VirtualFile generationDir = path != null? LocalFileSystem.getInstance().findFileByPath(path) : null;
+      if (generationDir != null && VfsUtil.isAncestor(generationDir, file, false)) {
         return true;
       }
     }