8037935: Javac -- final local String var referenced in binary/unary op in...

8037935: Javac -- final local String var referenced in binary/unary op in lambda produces code that does not verify
Summary: Remove over-zealous Attr optimization breaking lambdas
Reviewed-by: jjg, vromero

src/share/classes/com/sun/tools/javac/comp/Attr.java

@@ -3009,15 +3009,6 @@ public class Attr extends JCTree.Visitor {
                 Type ctype = cfolder.fold1(opc, argtype);
                 if (ctype != null) {
                     owntype = cfolder.coerce(ctype, owntype);
-
-                    // Remove constant types from arguments to
-                    // conserve space. The parser will fold concatenations
-                    // of string literals; the code here also
-                    // gets rid of intermediate results when some of the
-                    // operands are constant identifiers.
-                    if (tree.arg.type.tsym == syms.stringType.tsym) {
-                        tree.arg.type = syms.stringType;
-                    }
                 }
             }
         }
@@ -3051,18 +3042,6 @@ public class Attr extends JCTree.Visitor {
                 Type ctype = cfolder.fold2(opc, left, right);
                 if (ctype != null) {
                     owntype = cfolder.coerce(ctype, owntype);
-
-                    // Remove constant types from arguments to
-                    // conserve space. The parser will fold concatenations
-                    // of string literals; the code here also
-                    // gets rid of intermediate results when some of the
-                    // operands are constant identifiers.
-                    if (tree.lhs.type.tsym == syms.stringType.tsym) {
-                        tree.lhs.type = syms.stringType;
-                    }
-                    if (tree.rhs.type.tsym == syms.stringType.tsym) {
-                        tree.rhs.type = syms.stringType;
-                    }
                 }
             }
 

test/tools/javac/lambda/T8037935/LambdaWithBinOpConstRefToConstString.java

+/*
+ * Copyright (c) 2014, 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 8037935
+ * @summary Javac: final local String var referenced in binary/unary op in lambda produces code that does not verify
+ * @run main LambdaWithBinOpConstRefToConstString
+ */
+
+interface MyFI {
+    void accept();
+}
+
+public class LambdaWithBinOpConstRefToConstString {
+    public static void main(String[] args) {
+        final String CONSTANT_STRING_VALUE = "mwmwm";
+
+        MyFI consumeStrings = () -> {
+            System.out.println(" local constant: " + CONSTANT_STRING_VALUE);
+        };
+    }
+}