Remove unused variables

Change-Id: I15ab69c4d40fb8d9b97faceca256227cb9b893bd
diff --git a/src/builtin/PRED_$call_2.java b/src/builtin/PRED_$call_2.java
index 6139f2e..6376085 100644
--- a/src/builtin/PRED_$call_2.java
+++ b/src/builtin/PRED_$call_2.java
@@ -3,7 +3,6 @@
 import com.googlecode.prolog_cafe.exceptions.IllegalTypeException;
 import com.googlecode.prolog_cafe.exceptions.SystemException;
 import  com.googlecode.prolog_cafe.lang.*;
-import java.lang.reflect.*;
 /**
  * <code>'$call'/2</code><br>
  * @author Mutsunori Banbara (banbara@kobe-u.ac.jp)
@@ -30,9 +29,6 @@
 	String functor;
 	int arity;
 	Term[] args;
-	Class<?> clazz;
-	Constructor<?> constr;
-	Operation pred;
 
 	try {
 	    if (! (a1 instanceof SymbolTerm))
diff --git a/src/builtin/PRED_$get_instances_2.java b/src/builtin/PRED_$get_instances_2.java
index 707e8cd..d919bb9 100644
--- a/src/builtin/PRED_$get_instances_2.java
+++ b/src/builtin/PRED_$get_instances_2.java
@@ -24,7 +24,6 @@
         Term a1, a2;
         a1 = arg1;
         a2 = arg2;
-	int idx;
 
 	a1 = a1.dereference();
 	if (Prolog.Nil.equals(a1))
diff --git a/src/builtin/PRED_$hash_remove_first_3.java b/src/builtin/PRED_$hash_remove_first_3.java
index 048bffe..f0452bf 100644
--- a/src/builtin/PRED_$hash_remove_first_3.java
+++ b/src/builtin/PRED_$hash_remove_first_3.java
@@ -12,8 +12,6 @@
    @version 1.0
 */
 class PRED_$hash_remove_first_3 extends Predicate.P3 {
-    private static final SymbolTerm SYM_NIL = Prolog.Nil;
-
     public PRED_$hash_remove_first_3(Term a1, Term a2, Term a3, Operation cont) {
         arg1 = a1;
         arg2 = a2;
diff --git a/src/builtin/PRED_keysort_2.java b/src/builtin/PRED_keysort_2.java
index 6c5fa46..764efe6 100644
--- a/src/builtin/PRED_keysort_2.java
+++ b/src/builtin/PRED_keysort_2.java
@@ -27,7 +27,7 @@
 	a1 = arg1;
 	a2 = arg2;
 	int len;
-	Term tmp, tmp2;
+	Term tmp;
 	Term[] list;
 
 	a1 = a1.dereference();
diff --git a/src/repl/PrologMain.java b/src/repl/PrologMain.java
index 1c36e86..4a51b93 100644
--- a/src/repl/PrologMain.java
+++ b/src/repl/PrologMain.java
@@ -46,7 +46,6 @@
 
     public static void main(String argv[]) {
 	BlockingPrologControl p;
-	String goal;
 	try {
 	    System.err.println("\n" + VERSION); 
 	    System.err.println(COPYRIGHT);