--- a/langtools/src/share/classes/com/sun/tools/javac/tree/TreeInfo.java	Thu Sep 02 18:26:21 2010 -0700
+++ b/langtools/src/share/classes/com/sun/tools/javac/tree/TreeInfo.java	Fri Sep 03 11:25:43 2010 +0530
@@ -501,6 +501,10 @@
                 if (that.sym == sym) result = that;
                 else super.visitVarDef(that);
             }
+            public void visitTypeParameter(JCTypeParameter that) {
+                if (that.type.tsym == sym) result = that;
+                else super.visitTypeParameter(that);
+            }
         }
         DeclScanner s = new DeclScanner();
         tree.accept(s);

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/langtools/test/tools/javac/T6458823/MyProcessor.java	Fri Sep 03 11:25:43 2010 +0530
@@ -0,0 +1,55 @@
+ /*
+  * Copyright (c) 2010, 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.
+  */
+
+import java.util.Set;
+import javax.annotation.processing.*;
+import javax.lang.model.element.*;
+import javax.lang.model.util.ElementFilter;
+import javax.lang.model.SourceVersion;
+import static javax.tools.Diagnostic.Kind.*;
+
+@SupportedAnnotationTypes("*")
+public class MyProcessor extends AbstractProcessor {
+    private Messager messager;
+    public void init(ProcessingEnvironment processingEnv) {
+        this.messager = processingEnv.getMessager();
+    }
+
+    public boolean process(Set<? extends TypeElement> tes, RoundEnvironment renv) {
+        if (!renv.processingOver()) {
+            for(TypeElement e : ElementFilter.typesIn(renv.getRootElements())) {
+                for (TypeParameterElement tp : e.getTypeParameters()) {
+                    if (tp.getSimpleName().toString().length() > 1) {
+                        messager.printMessage(WARNING,
+                            "Type param names should be of length 1", tp);
+                    }
+                }
+            }
+        }
+        return true;
+    }
+
+    public SourceVersion getSupportedSourceVersion() {
+        return SourceVersion.latest();
+    }
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/langtools/test/tools/javac/T6458823/T6458823.java	Fri Sep 03 11:25:43 2010 +0530
@@ -0,0 +1,87 @@
+/*
+ * Copyright (c) 2010, 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 6458823
+ * @summary Messager messages on TypeParamterElements to not include position information.
+ *
+ * @compile MyProcessor.java T6458823.java
+ * @run main T6458823
+ */
+
+import java.io.File;
+import java.io.IOException;
+import java.io.Writer;
+import java.net.URISyntaxException;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import javax.tools.Diagnostic;
+import javax.tools.DiagnosticCollector;
+import javax.tools.JavaCompiler;
+import javax.tools.JavaCompiler.CompilationTask;
+import javax.tools.JavaFileObject;
+import javax.tools.StandardJavaFileManager;
+import javax.tools.ToolProvider;
+
+public class T6458823 {
+    public static void main(String[] args) throws Exception {
+        JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
+        if (compiler == null) {
+            throw new RuntimeException("can't get javax.tools.JavaCompiler!");
+        }
+        DiagnosticCollector<JavaFileObject> diagColl =
+            new DiagnosticCollector<JavaFileObject>();
+        StandardJavaFileManager fm = compiler.getStandardFileManager(null, null, null);
+        List<String> options = new ArrayList<String>();
+        options.add("-processor");
+        options.add("MyProcessor");
+        options.add("-proc:only");
+        List<File> files = new ArrayList<File>();
+        files.add(new File(T6458823.class.getResource("TestClass.java").toURI()));
+        final CompilationTask task = compiler.getTask(null, fm, diagColl,
+            options, null, fm.getJavaFileObjectsFromFiles(files));
+        task.call();
+        int diagCount = 0;
+        for (Diagnostic<? extends JavaFileObject> diag : diagColl.getDiagnostics()) {
+            if (diag.getKind() != Diagnostic.Kind.WARNING) {
+                throw new AssertionError("Only warnings expected");
+            }
+            System.out.println(diag);
+            if (diag.getPosition() == Diagnostic.NOPOS) {
+                throw new AssertionError("No position info in message");
+            }
+            if (diag.getSource() == null) {
+                throw new AssertionError("No source info in message");
+            }
+            diagCount++;
+        }
+        if (diagCount != 2) {
+            throw new AssertionError("unexpected number of warnings: " +
+                diagCount + ", expected: 2");
+        }
+    }
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/langtools/test/tools/javac/T6458823/TestClass.java	Fri Sep 03 11:25:43 2010 +0530
@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2010, 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.
+ */
+
+class TestClass<XYZ, ABC> {
+}