Attachment #205874 for bug #359284




			"SUCCESS"
		);
}
// https://bugs.eclipse.org/bugs/show_bug.cgi?id=359284
// Verify that needless checkcast is not emitted.
public void test062() throws Exception {
	String source =
		"public class X {\n" +
	    "public X() {\n" +
	    "    Object[] x = null;\n" +
	    "}\n" +
	    "}\n";
		this.runConformTest(
				new String[] {
					"X.java",
					source
				},
				""
			);
		String expectedOutput = 
				"public class X {\n" + 
				"  \n" + 
				"  // Method descriptor #6 ()V\n" + 
				"  // Stack: 1, Locals: 2\n" + 
				"  public X();\n" + 
				"    0  aload_0 [this]\n" + 
				"    1  invokespecial java.lang.Object() [8]\n" + 
				"    4  aconst_null\n" + 
				"    5  astore_1 [x]\n" + 
				"    6  return\n" + 
				"      Line numbers:\n" + 
				"        [pc: 0, line: 2]\n" + 
				"        [pc: 4, line: 3]\n" + 
				"        [pc: 6, line: 4]\n" + 
				"      Local variable table:\n" + 
				"        [pc: 0, pc: 7] local: this index: 0 type: X\n" + 
				"        [pc: 6, pc: 7] local: x index: 1 type: java.lang.Object[]\n" + 
				"}";
		File f = new File(OUTPUT_DIR + File.separator + "X.class");
		byte[] classFileBytes = org.eclipse.jdt.internal.compiler.util.Util.getFileByteContent(f);
		ClassFileBytesDisassembler disassembler = ToolFactory.createDefaultClassFileBytesDisassembler();
		String result = disassembler.disassemble(classFileBytes, "\n", ClassFileBytesDisassembler.DETAILED);
		int index = result.indexOf(expectedOutput);
		if (index == -1 || expectedOutput.length() == 0) {
			System.out.println(Util.displayString(result, 3));
		}
		if (index == -1) {
			assertEquals("Wrong contents", expectedOutput, result);
		}
}
public static Class testClass() {
	return CastTest.class;
}

Lines 246-254 Link Here

(-)a/org.eclipse.jdt.core/buildnotes_jdt-core.html (-3 / +1 lines)
246	</li>	246	</li>
247	</ul>	247	</ul>
248	<h3>Problem Reports Fixed</h3>	248	<h3>Problem Reports Fixed</h3>
249	<a href="https://bugs.eclipse.org/bugs/show_bug.cgi?id=359284">359284</a>	249	<a href="https://bugs.eclipse.org/bugs/show_bug.cgi?id=359943">359943</a>
250	Unnecessary checkast from null
251	<br><a href="https://bugs.eclipse.org/bugs/show_bug.cgi?id=359943">359943</a>
252	invokedynamic in generated class file is not correctly recognized by the eclipse compiler	250	invokedynamic in generated class file is not correctly recognized by the eclipse compiler
253	<br><a href="https://bugs.eclipse.org/bugs/show_bug.cgi?id=360644">360644</a>	251	<br><a href="https://bugs.eclipse.org/bugs/show_bug.cgi?id=360644">360644</a>
254	Scope.isDefinedInSameUnit(ReferenceBinding) fails for a ParameterizedTypeBinding	252	Scope.isDefinedInSameUnit(ReferenceBinding) fails for a ParameterizedTypeBinding

Lines 53-58 Link Here

(-)a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/ArrayReference.java (+20 lines)
53	public void generateAssignment(BlockScope currentScope, CodeStream codeStream, Assignment assignment, boolean valueRequired) {	53	public void generateAssignment(BlockScope currentScope, CodeStream codeStream, Assignment assignment, boolean valueRequired) {
54	int pc = codeStream.position;	54	int pc = codeStream.position;
55	this.receiver.generateCode(currentScope, codeStream, true);	55	this.receiver.generateCode(currentScope, codeStream, true);
		56	if (this.receiver instanceof CastExpression // ((type[])null)[0]
		57	&& ((CastExpression)this.receiver).innermostCastedExpression().resolvedType == TypeBinding.NULL){
		58	codeStream.checkcast(this.receiver.resolvedType);
		59	}
56	codeStream.recordPositionsFrom(pc, this.sourceStart);	60	codeStream.recordPositionsFrom(pc, this.sourceStart);
57	this.position.generateCode(currentScope, codeStream, true);	61	this.position.generateCode(currentScope, codeStream, true);
58	assignment.expression.generateCode(currentScope, codeStream, true);	62	assignment.expression.generateCode(currentScope, codeStream, true);
Lines 68-73 Link Here
68	public void generateCode(BlockScope currentScope, CodeStream codeStream, boolean valueRequired) {	72	public void generateCode(BlockScope currentScope, CodeStream codeStream, boolean valueRequired) {
69	int pc = codeStream.position;	73	int pc = codeStream.position;
70	this.receiver.generateCode(currentScope, codeStream, true);	74	this.receiver.generateCode(currentScope, codeStream, true);
		75	if (this.receiver instanceof CastExpression // ((type[])null)[0]
		76	&& ((CastExpression)this.receiver).innermostCastedExpression().resolvedType == TypeBinding.NULL){
		77	codeStream.checkcast(this.receiver.resolvedType);
		78	}
71	this.position.generateCode(currentScope, codeStream, true);	79	this.position.generateCode(currentScope, codeStream, true);
72	codeStream.arrayAt(this.resolvedType.id);	80	codeStream.arrayAt(this.resolvedType.id);
73	// Generating code for the potential runtime type checking	81	// Generating code for the potential runtime type checking
Lines 91-96 Link Here
91		99
92	public void generateCompoundAssignment(BlockScope currentScope, CodeStream codeStream, Expression expression, int operator, int assignmentImplicitConversion, boolean valueRequired) {	100	public void generateCompoundAssignment(BlockScope currentScope, CodeStream codeStream, Expression expression, int operator, int assignmentImplicitConversion, boolean valueRequired) {
93	this.receiver.generateCode(currentScope, codeStream, true);	101	this.receiver.generateCode(currentScope, codeStream, true);
		102	if (this.receiver instanceof CastExpression // ((type[])null)[0]
		103	&& ((CastExpression)this.receiver).innermostCastedExpression().resolvedType == TypeBinding.NULL){
		104	codeStream.checkcast(this.receiver.resolvedType);
		105	}
94	this.position.generateCode(currentScope, codeStream, true);	106	this.position.generateCode(currentScope, codeStream, true);
95	codeStream.dup2();	107	codeStream.dup2();
96	codeStream.arrayAt(this.resolvedType.id);	108	codeStream.arrayAt(this.resolvedType.id);
Lines 120-125 Link Here
120		132
121	public void generatePostIncrement(BlockScope currentScope, CodeStream codeStream, CompoundAssignment postIncrement, boolean valueRequired) {	133	public void generatePostIncrement(BlockScope currentScope, CodeStream codeStream, CompoundAssignment postIncrement, boolean valueRequired) {
122	this.receiver.generateCode(currentScope, codeStream, true);	134	this.receiver.generateCode(currentScope, codeStream, true);
		135	if (this.receiver instanceof CastExpression // ((type[])null)[0]
		136	&& ((CastExpression)this.receiver).innermostCastedExpression().resolvedType == TypeBinding.NULL){
		137	codeStream.checkcast(this.receiver.resolvedType);
		138	}
123	this.position.generateCode(currentScope, codeStream, true);	139	this.position.generateCode(currentScope, codeStream, true);
124	codeStream.dup2();	140	codeStream.dup2();
125	codeStream.arrayAt(this.resolvedType.id);	141	codeStream.arrayAt(this.resolvedType.id);
Lines 155-160 Link Here
155		171
156	public TypeBinding resolveType(BlockScope scope) {	172	public TypeBinding resolveType(BlockScope scope) {
157	this.constant = Constant.NotAConstant;	173	this.constant = Constant.NotAConstant;
		174	if (this.receiver instanceof CastExpression // no cast check for ((type[])null)[0]
		175	&& ((CastExpression)this.receiver).innermostCastedExpression() instanceof NullLiteral) {
		176	this.receiver.bits \|= ASTNode.DisableUnnecessaryCastCheck; // will check later on
		177	}
158	TypeBinding arrayType = this.receiver.resolveType(scope);	178	TypeBinding arrayType = this.receiver.resolveType(scope);
159	if (arrayType != null) {	179	if (arrayType != null) {
160	this.receiver.computeConversion(scope, arrayType, arrayType);	180	this.receiver.computeConversion(scope, arrayType, arrayType);

Lines 133-138 Link Here

(-)a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/LocalDeclaration.java (+7 lines)
133	break generateInit;	133	break generateInit;
134	}	134	}
135	this.initialization.generateCode(currentScope, codeStream, true);	135	this.initialization.generateCode(currentScope, codeStream, true);
		136	// 26903, need extra cast to store null in array local var
		137	if (this.binding.type.isArrayType()
		138	&& (this.initialization.resolvedType == TypeBinding.NULL // arrayLoc = null
		139	\|\| ((this.initialization instanceof CastExpression) // arrayLoc = (type[])null
		140	&& (((CastExpression)this.initialization).innermostCastedExpression().resolvedType == TypeBinding.NULL)))){
		141	codeStream.checkcast(this.binding.type);
		142	}
136	codeStream.store(this.binding, false);	143	codeStream.store(this.binding, false);
137	if ((this.bits & ASTNode.FirstAssignmentToLocal) != 0) {	144	if ((this.bits & ASTNode.FirstAssignmentToLocal) != 0) {
138	/* Variable may have been initialized during the code initializing it	145	/* Variable may have been initialized during the code initializing it

Lines 350-355 Link Here

(-)a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/SingleNameReference.java (+8 lines)
350	}	350	}
351	return;	351	return;
352	}	352	}
		353	// 26903, need extra cast to store null in array local var
		354	if (localBinding.type.isArrayType()
		355	&& (assignment.expression.resolvedType == TypeBinding.NULL // arrayLoc = null
		356	\|\| ((assignment.expression instanceof CastExpression) // arrayLoc = (type[])null
		357	&& (((CastExpression)assignment.expression).innermostCastedExpression().resolvedType == TypeBinding.NULL)))){
		358	codeStream.checkcast(localBinding.type);
		359	}
		360
353	// normal local assignment (since cannot store in outer local which are final locations)	361	// normal local assignment (since cannot store in outer local which are final locations)
354	codeStream.store(localBinding, valueRequired);	362	codeStream.store(localBinding, valueRequired);
355	if ((this.bits & ASTNode.FirstAssignmentToLocal) != 0) { // for local variable debug attributes	363	if ((this.bits & ASTNode.FirstAssignmentToLocal) != 0) { // for local variable debug attributes

Return to bug 359284

Lines 2374-2426 Link Here

(-)a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/CastTest.java (-47 lines)
2374	"SUCCESS"	2374	"SUCCESS"
2375	);	2375	);
2376	}	2376	}
2377	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=359284
2378	// Verify that needless checkcast is not emitted.
2379	public void test062() throws Exception {
2380	String source =
2381	"public class X {\n" +
2382	"public X() {\n" +
2383	" Object[] x = null;\n" +
2384	"}\n" +
2385	"}\n";
2386	this.runConformTest(
2387	new String[] {
2388	"X.java",
2389	source
2390	},
2391	""
2392	);
2393	String expectedOutput =
2394	"public class X {\n" +
2395	" \n" +
2396	" // Method descriptor #6 ()V\n" +
2397	" // Stack: 1, Locals: 2\n" +
2398	" public X();\n" +
2399	" 0 aload_0 [this]\n" +
2400	" 1 invokespecial java.lang.Object() [8]\n" +
2401	" 4 aconst_null\n" +
2402	" 5 astore_1 [x]\n" +
2403	" 6 return\n" +
2404	" Line numbers:\n" +
2405	" [pc: 0, line: 2]\n" +
2406	" [pc: 4, line: 3]\n" +
2407	" [pc: 6, line: 4]\n" +
2408	" Local variable table:\n" +
2409	" [pc: 0, pc: 7] local: this index: 0 type: X\n" +
2410	" [pc: 6, pc: 7] local: x index: 1 type: java.lang.Object[]\n" +
2411	"}";
2412	File f = new File(OUTPUT_DIR + File.separator + "X.class");
2413	byte[] classFileBytes = org.eclipse.jdt.internal.compiler.util.Util.getFileByteContent(f);
2414	ClassFileBytesDisassembler disassembler = ToolFactory.createDefaultClassFileBytesDisassembler();
2415	String result = disassembler.disassemble(classFileBytes, "\n", ClassFileBytesDisassembler.DETAILED);
2416	int index = result.indexOf(expectedOutput);
2417	if (index == -1 \|\| expectedOutput.length() == 0) {
2418	System.out.println(Util.displayString(result, 3));
2419	}
2420	if (index == -1) {
2421	assertEquals("Wrong contents", expectedOutput, result);
2422	}
2423	}
2424	public static Class testClass() {	2377	public static Class testClass() {
2425	return CastTest.class;	2378	return CastTest.class;
2426	}	2379	}