Description Olivier Thomann 2002-07-12 14:45:34 EDT

Test case:
public class X {
	
	public static final int CONST = 0x7fffffff;
    public static void main(String[] args) {

        int i = CONST;

        switch (i) {

            case CONST:
                System.out.println("SUCCESS");

                break;
        }
    }
}

This code compiles fine on Eclipse 2.0, but the resulting .class file executiuon
leads to VerifyError on a 1.3.1 VM.
java.lang.VerifyError: (class: X, method: main signature:
([Ljava/lang/String;)V) Illegal instruction found at offset 4
Exception in thread "main".

On a 1.4 VM the problem has been fixed. Looking at the Sun bug database, we
found the problem:
See Re: http://developer.java.sun.com/developer/bugParade/bugs/4411025.html for
further details.

The bytecodes generated by Eclipse are:
Method void main(java.lang.String[])
   0 ldc #16 <Integer 2147483647>
   2 istore_1
   3 iload_1
   4 tableswitch 2147483647 to 2147483647: default=32
	2147483647: 24
  24 getstatic #22 <Field java.io.PrintStream out>
  27 ldc #24 <String "SUCCESS">
  29 invokevirtual #30 <Method void println(java.lang.String)>
  32 return

The bytecodes generated by Sun 1.3.1 or 1.4 are:
Method void main(java.lang.String[])
   0 ldc #2 <Integer 2147483647>
   2 istore_1
   3 iload_1
   4 lookupswitch 1: default=32
	2147483647: 24
  24 getstatic #3 <Field java.io.PrintStream out>
  27 ldc #4 <String "SUCCESS">
  29 invokevirtual #5 <Method void println(java.lang.String)>
  32 return

The difference is the lookupswitch instead of a tableswitch. We might want to
generate a workaround to generate a lookupswitch if target < 1.4.