Index: compiler/org/eclipse/jdt/internal/compiler/ast/QualifiedTypeReference.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/QualifiedTypeReference.java,v
--- compiler/org/eclipse/jdt/internal/compiler/ast/QualifiedTypeReference.java	18 Mar 2010 16:22:38 -0000	1.50
+++ compiler/org/eclipse/jdt/internal/compiler/ast/QualifiedTypeReference.java	5 Dec 2010 17:35:31 -0000
@@ -7,6 +7,7 @@ 
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
+ *     Stephan Herrmann <stephan@cs.tu-berlin.de> - Contribution for Bug 331872 -  [compiler] NPE in Scope.createArrayType when attempting qualified access from type parameter
  *******************************************************************************/
 package org.eclipse.jdt.internal.compiler.ast;
 
@@ -84,7 +85,7 @@ 
 				return this.resolvedType;
 			if (i == 0 && this.resolvedType.isTypeVariable() && ((TypeVariableBinding) this.resolvedType).firstBound == null) { // cannot select from a type variable
 				scope.problemReporter().illegalAccessFromTypeVariable((TypeVariableBinding) this.resolvedType, this);
-				return null;
+				return new ProblemReferenceBinding(this.tokens, scope.environment().createMissingType(null, this.tokens), ProblemReasons.NotFound);
 			}
 			if (i <= last && isTypeUseDeprecated(this.resolvedType, scope)) {
 				reportDeprecatedType(this.resolvedType, scope, i);
Index: src/org/eclipse/jdt/core/tests/compiler/regression/ArrayTest.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/ArrayTest.java,v
--- src/org/eclipse/jdt/core/tests/compiler/regression/ArrayTest.java	27 Aug 2009 15:26:58 -0000	1.28
+++ src/org/eclipse/jdt/core/tests/compiler/regression/ArrayTest.java	5 Dec 2010 17:35:32 -0000
@@ -1,5 +1,5 @@ 
 /*******************************************************************************
- * Copyright (c) 2000, 2009 IBM Corporation and others.
+ * Copyright (c) 2000, 2010 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -7,6 +7,7 @@ 
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
+ *     Stephan Herrmann <stephan@cs.tu-berlin.de> - Contribution for Bug 331872 - [compiler] NPE in Scope.createArrayType when attempting qualified access from type parameter
  *******************************************************************************/
 package org.eclipse.jdt.core.tests.compiler.regression;
 import java.io.File;
@@ -544,4 +545,37 @@ 
 		assertEquals("unexpected bytecode sequence", expectedOutput, actualOutput);
 	}		
 }
+
+// https://bugs.eclipse.org/331872 -  [compiler] NPE in Scope.createArrayType when attempting qualified access from type parameter
+public void test018() throws Exception {
+	if (new CompilerOptions(getCompilerOptions()).complianceLevel < ClassFileConstants.JDK1_5)
+		return;
+	this.runNegativeTest(
+		new String[] {
+			"X.java",
+			"public class X<p> {\n" + 
+			"	void foo(p.O[] elems)  {\n" + 
+			"	}\n" +
+			"   void bar() {\n" +
+			"        foo(new Object[0]);\n" +
+			"   }\n" + 
+			"}\n",
+		},
+		"----------\n" + 
+		"1. ERROR in X.java (at line 2)\n" + 
+		"	void foo(p.O[] elems)  {\n" + 
+		"	         ^^^^^\n" + 
+		"Illegal qualified access from the type parameter p\n" + 
+		"----------\n" + 
+		"2. ERROR in X.java (at line 2)\n" + 
+		"	void foo(p.O[] elems)  {\n" + 
+		"	         ^^^\n" + 
+		"p.O cannot be resolved to a type\n" + 
+		"----------\n" + 
+		"3. ERROR in X.java (at line 5)\n" + 
+		"	foo(new Object[0]);\n" + 
+		"	^^^\n" + 
+		"The method foo(O[]) from the type X<p> refers to the missing type O\n" + 
+		"----------\n");
+}
 }