DO NOT REPLY [Bug 48270] New: Invalid stack map table tag & bad constant pool index with Java 1.6 bytecode

https://issues.apache.org/bugzilla/show_bug.cgi?id=48270

           Summary: Invalid stack map table tag & bad constant pool index
                    with Java 1.6 bytecode
           Product: BCEL
           Version: unspecified
          Platform: All
        OS/Version: All
            Status: NEW
          Severity: major
          Priority: P2
         Component: Main
        AssignedTo: [email protected]
        ReportedBy: [email protected]


The following code defines a class, lets BCEL parse and rewrite it without any
modification, then it tries to load it into the JVM.
================================================================
import org.apache.bcel.Repository;
import org.apache.bcel.classfile.JavaClass;

class TestClass {
    public void foo() {
        int a = 0;

        /* FIRST CONDITIONAL BLOCK */
        if (a == 1) {
            a = 0;
        }
        /* SECOND CONDITIONAL BLOCK */
        if (a == 1) {
            a = 0;
        }
    };
}

class MyClassLoader extends ClassLoader {
    public Class getTestClass() throws ClassNotFoundException {
        JavaClass jcl;
        jcl = Repository.lookupClass(TestClass.class);
        byte[] data = jcl.getBytes();
        return defineClass(TestClass.class.getName(), data, 0, data.length);
    }
}

public class Main {
    public static void main(String[] args) {
        try {
            MyClassLoader mcl = new MyClassLoader();
            mcl.getTestClass();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

================================================================

If both conditional blocks are present (i.e. not commented), the following
exception appears instead:

org.apache.bcel.classfile.ClassFormatException: Invalid Stack map table tag: 6
    at
org.apache.bcel.classfile.StackMapTableEntry.dump(StackMapTableEntry.java:143)
    at org.apache.bcel.classfile.StackMapTable.dump(StackMapTable.java:86)
    at org.apache.bcel.classfile.Code.dump(Code.java:154)
    at org.apache.bcel.classfile.FieldOrMethod.dump(FieldOrMethod.java:111)
    at org.apache.bcel.classfile.JavaClass.dump(JavaClass.java:317)
    at org.apache.bcel.classfile.JavaClass.getBytes(JavaClass.java:268)
    at MyClassLoader.getTestClass(Main.java:23)
    at Main.main(Main.java:32)


If only the second one is commented, the following exception is thrown:

Exception in thread "main" java.lang.ClassFormatError: Attribute name has bad
constant pool index 4608 in class file TestClass
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:621)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:466)
    at MyClassLoader.getTestClass(Main.java:24)
    at Main.main(Main.java:32)


If both conditional blocks are commented, or if the code is compiled with Java
1.5 compiler instead of 1.6, everything is OK.


This happens with BCEL revision 883394.

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