run.javac improvements:

+ more documentation for JavacHasABug.JavacBug6573446
+ new constant JavacHasABug.JavacBugIvarInterning
+ new constant JavacHasABug.JavacBug8297428
At this point GenericsRegressionTest_9 is ready to opt in to this mode

Author: stephan-herrmann

org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/AbstractRegressionTest.java

@@ -1154,6 +1154,8 @@ Excuse excuseFor(JavacCompiler compiler) {
 				new JavacHasABug(
 					MismatchType.EclipseErrorsJavacNone),
 			JavacBug6573446 = // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6573446 & https://bugs.eclipse.org/bugs/show_bug.cgi?id=190945
+							// updated link https://bugs.openjdk.org/browse/JDK-6573446
+							// see also confirmation https://mail.openjdk.org/archives/list/compiler-dev@openjdk.org/thread/TLIVNI7SPUVX646O7RTGG7IOYJVWSV47/
 				new JavacHasABug(
 					MismatchType.EclipseErrorsJavacNone),
 			JavacBug6575821 = // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6575821
@@ -1193,7 +1195,11 @@ Excuse excuseFor(JavacCompiler compiler) {
 			JavacBug8016196 = // https://bugs.openjdk.org/browse/JDK-8016196
 					new JavacHasABug(MismatchType.JavacErrorsEclipseNone),
 			JavacBug8016207 = // https://bugs.openjdk.org/browse/JDK-8016207 Widening of capture vars occurs at unspecified times
-					new JavacHasABug(MismatchType.EclipseErrorsJavacNone);
+					new JavacHasABug(MismatchType.EclipseErrorsJavacNone),
+			JavacBugIvarInterning = // https://mail.openjdk.org/pipermail/compiler-dev/2025-October/031866.html
+					new JavacHasABug(MismatchType.JavacErrorsEclipseNone),
+			JavacBug8297428 = // https://bugs.openjdk.org/browse/JDK-8297428
+					new JavacHasABug(MismatchType.JavacErrorsEclipseNone);
 
 		// bugs that have been fixed but that we've not identified
 		public static JavacHasABug

org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/GenericsRegressionTest_9.java

@@ -38,6 +38,19 @@ public static Test suite() {
 	return buildMinimalComplianceTestSuite(testClass(), F_9);
 }
 
+// ========= OPT-IN to run.javac mode: ===========
+@Override
+protected void setUp() throws Exception {
+	this.runJavacOptIn = true;
+	super.setUp();
+}
+@Override
+protected void tearDown() throws Exception {
+	super.tearDown();
+	this.runJavacOptIn = false; // do it last, so super can still clean up
+}
+// =================================================
+
 // vanilla test case
 public void testBug488663_001() {
 	this.runConformTest(
@@ -1139,7 +1152,8 @@ public static <T> IQuery<T> createCompoundQuery(Collection<? extends List<? exte
 	});
 }
 public void testGH3948() {
-	runConformTest(new String[] {
+	Runner runner = new Runner();
+	runner.testFiles = new String[] {
 			"Foo.java",
 			"""
 			import java.util.Collections;
@@ -1169,7 +1183,9 @@ public static <U> void test(Function<Foo, List<U>> getter, BiConsumer<Foo, List<
 			    public static interface Bar{}
 			}
 			"""
-		});
+		};
+	runner.javacTestOptions = JavacHasABug.JavacBug8297428;
+	runner.runConformTest();
 }
 public void testGH4022a() {
 	runConformTest(new String[] {
@@ -1254,7 +1270,8 @@ public static void main(String[] args) {
 		});
 }
 public void testGH4039() {
-	runConformTest(new String[] {
+	Runner runner = new Runner();
+	runner.testFiles = new String[] {
 		"CollectionsSortReproducer.java",
 		"""
 		import java.util.Collection;
@@ -1274,7 +1291,9 @@ public static void main(String[] args) {
 			}
 		}
 		"""
-	});
+	};
+	runner.javacTestOptions = JavacHasABug.JavacBugIvarInterning;
+	runner.runConformTest();
 }
 
 public void testGH4003() {