8264306: Non deterministic generation of java/lang/invoke/MemberName.class

Reviewed-by: shade, jfranck

Author: lahodaj

src/jdk.compiler/share/classes/com/sun/tools/javac/comp/TransPatterns.java

@@ -56,6 +56,7 @@
 import com.sun.tools.javac.util.Names;
 import com.sun.tools.javac.util.Options;
 
+import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.Map.Entry;
 
@@ -70,7 +71,6 @@
 import com.sun.tools.javac.tree.JCTree.LetExpr;
 import com.sun.tools.javac.tree.TreeInfo;
 import com.sun.tools.javac.util.List;
-import java.util.HashMap;
 
 /**
  * This pass translates pattern-matching constructs, such as instanceof <pattern>.
@@ -387,7 +387,7 @@ class BasicBindingContext extends BindingContext {
 
         public BasicBindingContext() {
             this.parent = bindingContext;
-            this.hoistedVarMap = new HashMap<>();
+            this.hoistedVarMap = new LinkedHashMap<>();
         }
 
         @Override

test/langtools/tools/javac/patterns/StablePatternDesugaring.java

@@ -0,0 +1,118 @@
+/*
+ * Copyright (c) 2021, 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 8264306
+ * @summary Verify patterns are desugaring in a reproducible manner
+ * @library /tools/lib /tools/javac/lib
+ * @modules
+ *      jdk.compiler/com.sun.tools.javac.api
+ *      jdk.compiler/com.sun.tools.javac.file
+ *      jdk.compiler/com.sun.tools.javac.main
+ *      jdk.compiler/com.sun.tools.javac.util
+ * @build toolbox.ToolBox toolbox.JavacTask
+ * @compile StablePatternDesugaring.java
+ * @run main StablePatternDesugaring
+ */
+
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.Arrays;
+import toolbox.ToolBox;
+import toolbox.JavacTask;
+
+public class StablePatternDesugaring {
+    protected ToolBox tb;
+
+    StablePatternDesugaring() {
+        tb = new ToolBox();
+    }
+
+    public static void main(String... args) throws Exception {
+        new StablePatternDesugaring().run();
+    }
+
+    void run() throws Exception {
+        String code = """
+                      public class T {
+                          private boolean t(Object o) {
+                              if (o instanceof String s) {
+                                  return s.isEmpty();
+                              } else if (o instanceof CharSequence cs) {
+                                  return cs.isEmpty();
+                              } else if (o instanceof Integer i) {
+                                  return i != 0;
+                              } else if (o instanceof Float f) {
+                                  return f != 0;
+                              } else {
+                                  return false;
+                              }
+                          }
+                      }
+                      """;
+        Path base = Paths.get(".");
+        Path src = base.resolve("src");
+
+        tb.writeJavaFiles(src, code);
+
+        Path classes1 = base.resolve("classes1");
+
+        if (Files.isDirectory(classes1)) {
+            tb.cleanDirectory(classes1);
+        } else {
+            Files.createDirectories(classes1);
+        }
+
+        new JavacTask(tb)
+            .files(tb.findJavaFiles(src))
+            .outdir(classes1)
+            .run()
+            .writeAll();
+
+        byte[] expected = Files.readAllBytes(classes1.resolve("T.class"));
+
+        for (int i = 0; i < 10; i++) {
+            Path classes2 = base.resolve("classes2");
+
+            if (Files.isDirectory(classes2)) {
+                tb.cleanDirectory(classes2);
+            } else {
+                Files.createDirectories(classes2);
+            }
+
+            new JavacTask(tb)
+                .files(tb.findJavaFiles(src))
+                .outdir(classes2)
+                .run()
+                .writeAll();
+
+            byte[] actual = Files.readAllBytes(classes2.resolve("T.class"));
+
+            if (!Arrays.equals(expected, actual)) {
+                throw new AssertionError("Classfiles differ!");
+            }
+        }
+    }
+}