undefect. CWE-407 — 63 sites patched across 27 ecosystems

Authors: russell@unturf.com · brackishbert@gmail.com · foxhop.net · TimeHexOn.com Patches, unit tests, benchmarks, whitepaper, and outreach briefs. Public domain — no copyright claimed. Use freely.
2026-03-26 17:11:57 -04:00 · 2026-03-26 17:11:57 -04:00 · 0a580b313d
commit 0a580b313d
70422 changed files with 17213626 additions and 0 deletions
--- a/test/langtools/tools/javac/patterns/MatchExceptionTest.java
+++ b/test/langtools/tools/javac/patterns/MatchExceptionTest.java
@ -0,0 +1,141 @@
+/*
+ * Copyright (c) 2022, 2024, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8297118
+ * @summary Verify javac uses MatchException or IncompatibleClassChangeError for exhaustive switches
+ * @library /tools/lib
+ * @modules jdk.compiler/com.sun.tools.javac.api
+ *          jdk.compiler/com.sun.tools.javac.main
+ * @build toolbox.ToolBox toolbox.JavacTask
+ * @run main MatchExceptionTest
+ */
+
+import java.nio.file.Path;
+
+import java.lang.classfile.*;
+import java.lang.classfile.constantpool.ClassEntry;
+import java.lang.classfile.constantpool.ConstantPool;
+import java.lang.classfile.constantpool.PoolEntry;
+import java.util.Arrays;
+
+import toolbox.JavacTask;
+import toolbox.TestRunner;
+import toolbox.ToolBox;
+
+public class MatchExceptionTest extends TestRunner {
+    private static final String JAVA_VERSION = System.getProperty("java.specification.version");
+    private static final String TEST_METHOD = "test";
+
+    ToolBox tb;
+    ClassModel cf;
+
+    public MatchExceptionTest() {
+        super(System.err);
+        tb = new ToolBox();
+    }
+
+    public static void main(String[] args) throws Exception {
+        MatchExceptionTest t = new MatchExceptionTest();
+        t.runTests();
+    }
+
+    @Test
+    public void testNestedPatternVariablesBytecode() throws Exception {
+        String codeStatement = """
+                class Test {
+                    void test(E e) {
+                      switch (e) {
+                          case null -> {}
+                          case S -> {}
+                      };
+                    }
+                    enum E { S; }
+                }""";
+        String codeExpression = """
+                class Test {
+                    int test(E e) {
+                      return switch (e) {
+                          case S -> 0;
+                      };
+                    }
+                    enum E { S; }
+                }""";
+        record Setup(boolean hasMatchException, String... options) {
+            public String toString() {
+                return "Setup[hasMatchException=" + hasMatchException +
+                       ", options=" + Arrays.toString(options) + "]";
+            }
+        }
+        Setup[] variants = new Setup[] {
+            new Setup(false, "--release", "20"),
+            new Setup(true),
+        };
+        record Source(String source, boolean needs21) {}
+        Source[] sources = new Source[] {
+            new Source(codeStatement, true),
+            new Source(codeExpression, false),
+        };
+        Path curPath = Path.of(".");
+        for (Source source : sources) {
+            for (Setup variant : variants) {
+                if (source.needs21 &&
+                    !Arrays.asList(variant.options).contains("21")) {
+                    continue;
+                }
+                new JavacTask(tb)
+                        .options(variant.options)
+                        .sources(source.source)
+                        .outdir(curPath)
+                        .run();
+
+                cf = ClassFile.of().parse(curPath.resolve("Test.class"));
+                boolean incompatibleClassChangeErrror = false;
+                boolean matchException = false;
+                for (PoolEntry pe : cf.constantPool()) {
+                    if (pe instanceof ClassEntry clazz) {
+                        incompatibleClassChangeErrror |= clazz.name().equalsString(
+                                "java/lang/IncompatibleClassChangeError");
+                        matchException |= clazz.name().equalsString("java/lang/MatchException");
+                    }
+                }
+                if (variant.hasMatchException) {
+                    assertTrue("Expected MatchException (" + variant + ")", matchException);
+                    assertTrue("Did not expect IncompatibleClassChangeError (" + variant + ")",
+                               !incompatibleClassChangeErrror);
+                } else {
+                    assertTrue("Did not expect MatchException (" + variant + ")", !matchException);
+                    assertTrue("Expected IncompatibleClassChangeError (" + variant + ")",
+                               incompatibleClassChangeErrror);
+                }
+            }
+        }
+    }
+
+    void assertTrue(String message, boolean b) {
+        if (!b) {
+            throw new AssertionError(message);
+        }
+    }
+}