javac compiler crashes while compiling the attached test program.
Versions affected: at least from 1.5 to the latest builds of 1.6
How to reproduce: javac Tester_7.java


An exception has occurred in the compiler (1.6.0-rc-fastdebug). Please file a bug at the Java Developer Connection (http://java.sun.com/webapps/bugreport) after checking the Bug Parade for duplicates. Include your program and the following diagnostic in your report. Thank you.
java.lang.NullPointerException
        at com.sun.tools.javac.code.Types.lub(Types.java:2310)
        at com.sun.tools.javac.code.Types.lub(Types.java:2324)
        at com.sun.tools.javac.code.Types.lub(Types.java:2324)
        at com.sun.tools.javac.code.Types.lub(Types.java:2299)
        at com.sun.tools.javac.comp.Attr.condType1(Attr.java:931)
        at com.sun.tools.javac.comp.Attr.condType(Attr.java:854)
        at com.sun.tools.javac.comp.Attr.visitConditional(Attr.java:835)
        at com.sun.tools.javac.tree.JCTree$JCConditional.accept(JCTree.java:1021)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:289)
        at com.sun.tools.javac.comp.Attr.attribExpr(Attr.java:304)
        at com.sun.tools.javac.comp.Attr.visitAssign(Attr.java:1480)
        at com.sun.tools.javac.tree.JCTree$JCAssign.accept(JCTree.java:1344)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:289)
        at com.sun.tools.javac.comp.Attr.attribExpr(Attr.java:311)
        at com.sun.tools.javac.comp.Attr.visitExec(Attr.java:944)
        at com.sun.tools.javac.tree.JCTree$JCExpressionStatement.accept(JCTree.java:1074)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:289)
        at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:324)
        at com.sun.tools.javac.comp.Attr.attribStats(Attr.java:340)
        at com.sun.tools.javac.comp.Attr.visitBlock(Attr.java:642)
        at com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:739)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:289)
        at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:324)
        at com.sun.tools.javac.comp.Attr.visitMethodDef(Attr.java:561)
        at com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:639)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:289)
        at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:324)
        at com.sun.tools.javac.comp.Attr.attribClassBody(Attr.java:2540)
        at com.sun.tools.javac.comp.Attr.attribClass(Attr.java:2472)
        at com.sun.tools.javac.comp.Attr.attribClass(Attr.java:2408)
        at com.sun.tools.javac.main.JavaCompiler.attribute(JavaCompiler.java:891)
        at com.sun.tools.javac.main.JavaCompiler.attribute(JavaCompiler.java:867)
        at com.sun.tools.javac.main.JavaCompiler.compile2(JavaCompiler.java:660)
        at com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:633)
        at com.sun.tools.javac.main.Main.compile(Main.java:761)
        at com.sun.tools.javac.main.Main.compile(Main.java:686)
        at com.sun.tools.javac.main.Main.compile(Main.java:675)
        at com.sun.tools.javac.Main.compile(Main.java:70)
        at com.sun.tools.javac.Main.main(Main.java:55)