diff --git a/sources/zweic/Generator.scala b/sources/zweic/Generator.scala
index 6ab57c7..67fce54 100644
--- a/sources/zweic/Generator.scala
+++ b/sources/zweic/Generator.scala
@@ -349,6 +349,7 @@
 			}
 		}
 
+
 		  // get 'receiver' and put it as 'this' on the stack
 		  genLoad(receiver, targetReg);
 
diff --git a/tests/5/impossible.zwei b/tests/5/impossible.zwei
new file mode 100644
index 0000000..83bb74b
--- /dev/null
+++ b/tests/5/impossible.zwei
@@ -0,0 +1,414 @@
+class List {
+	Int isEmpty() { return this.isEmpty() }
+	Int head() { return this.head() }
+	List tail() { return this.tail() }
+	List cons(Int x) { return this.cons(x) }
+}
+
+class Cons extends List {
+	Int head;
+	List tail;
+	Int isEmpty() { return false }
+	Int head() { return this.head }
+	List tail() { return this.tail }
+	List cons(Int x) { return new Cons(x, this) }
+}
+
+class Nil extends List {
+	Int isEmpty() { return true }
+	List cons(Int x) { return new Cons(x, this) }
+}
+
+
+class String {
+	
+	// print a string
+	Null print(List l) {		
+		while(!l.isEmpty()) {
+			printChar(l.head());
+			l = l.tail();
+		}
+
+	}
+	
+	// print a string with \n
+	Null println(List l) {			
+		this.print(l);
+		printChar(10);
+	}
+	
+	// returns the length of a string
+	Int length(List l) {
+		Int len = 0;
+		while(!l.isEmpty()) {
+			len = len+1;
+			l = l.tail();
+		}
+		return len
+	}
+	
+	// reverse a string
+	List reverse(List l) {
+		List rev = new Nil();
+		while(!l.isEmpty()) {
+			rev = new Cons(l.head(), rev);
+			l = l.tail();
+		}
+		return rev
+	}
+	
+	// return the substring from start to end (without)
+	List substring(List l, Int start, Int end) {
+		Int len = end - start;
+		List result = new Nil();
+			
+		while(start > 0) {
+			l = l.tail();	
+			start = start-1; 
+		}				
+		while(len > 0) {
+			result = new Cons(l.head(), result);
+			l = l.tail();
+			len = len-1;
+		}				
+		return this.reverse(result)
+	}
+	
+	// reads a string from the console
+	List readString() {
+		List res = new Nil();
+		Int c = readChar;
+		while(c != 10) {
+			res = new Cons(c, res);
+			c = readChar;		
+		}
+		return this.reverse(res)
+	}
+	
+	// compare two strings
+	Int eq(List l1, List l2) {
+		
+		Int cont = true;
+		Int eq = true;
+		while(cont) {
+			if(l1.isEmpty() && l2.isEmpty()) {
+				cont = false;
+			} else {
+				if(l1.isEmpty() || l2.isEmpty()) {
+					cont = false;
+					eq = false;
+				} else {
+					if(l1.head() != l2.head()) {
+						eq = false; 
+						cont = false;
+					} else {
+						l1 = l1.tail();
+						l2 = l2.tail();
+					};
+				};
+			};
+		}
+		return eq					
+	}
+	
+}
+
+class Names extends String {
+	
+	Null printWelcome() {
+		this.println("*************************");
+		this.println("*** Play with strings ***");
+		this.println("*************************");	
+	}
+	
+	List askName(List ask) {
+		this.print(" ");
+		this.println(ask);
+		this.print(" ->");
+		List name = this.readString();
+		this.print(" OK, the name is ");
+		this.println(name);
+		return name
+	}
+	
+	Null main() {
+		this.printWelcome();
+		List name1 = this.askName("What is your name?");
+		List name2 = this.askName("And your brother's?");
+		this.print(" The names are: ");
+		this.println(if(this.eq(name1, name2)) "equals ;-)" else "different :-0");	
+		this.print(" Your name begins with: ");
+		this.println(this.substring(name1, 0, 1));
+		this.print(" Brother's name reversed: ");
+		this.println(this.substring(this.reverse(name2), 1, this.length(this.reverse(name2))));
+	}
+	
+}
+
+class Real {
+	Int left;
+	Int right;
+	
+	Null print() {
+		printInt(this.left);
+		new String().print(".");
+		printInt(this.right);
+	}
+	
+	Real normalize() {
+		Real r = this;
+		Int cont = true;
+		while(cont) {
+			cont = r.right > 0;
+			cont = if(cont) r.right % 10 == 0 else false;
+			r = if(cont) new Real(r.left, r.right / 10) else r; 
+		}
+		return r
+	}
+	
+	Int length() {
+		Int l = 1;
+		Int div = 10;
+		while(this.right / div > 0) {
+			l = l+1;
+			div = div*10;
+		} 
+		l = if(this.right % 10 == 0) l-1 else l;
+		return l	
+	}
+	
+	Int max(Int i1, Int i2) {
+		return if(i1 > i2) i1 else i2
+	}
+	
+	Int min(Int i1, Int i2) {
+		return if(i1 < i2) i1 else i2
+	}
+	
+	Real sum(Real that) {
+		Real thiz = this;
+		Int lenMax = this.max(this.right, that.right);
+		Int lenMin = this.min(this.right, that.right);
+		Int diff = new Real(0, lenMax).length() - new Real(0, lenMin).length();
+		Int factor = 1;
+		while(diff > 0) {			
+			factor = factor*10;
+			diff = diff-1;					
+		}
+		if(this.right > that.right) {
+			that = new Real(that.left, that.right * factor);
+		} else {
+			thiz = new Real(this.left, this.right * factor);
+		};
+		
+		Int Tleft = thiz.left + that.left;
+		Int Tright = thiz.right + that.right;				
+		
+		Real result = new Real(Tleft, Tright).normalize();
+		return result
+	}
+
+}
+
+class Reals {
+
+	Real readReal() {
+		String s = new String();
+		s.println(" Type a real");
+		s.print(" ->");
+		Int left = readInt;
+		s.print(" ->");
+		printInt(left);
+		s.print(".");
+		Int right = readInt;
+		Real r = new Real(left, right).normalize();
+		s.print(" got ");
+		r.print();
+		s.println("");
+		return r
+	}	
+	
+	Null main() {	
+		String s = new String();
+		s.println("*************************");
+		s.println("**** Play with reals ****");
+		s.println("* With some limitations *");
+		s.println("*************************");	
+		Real r1 = this.readReal();
+		Real r2 = this.readReal();
+		s.print(" The sum is ");
+		r1.sum(r2).print();
+		s.println("");
+	}
+
+}
+
+class Compop extends String {
+
+	Null test() {
+	
+		Int i = 0;
+		
+		this.println(" ------------------------");
+		this.println(" -> test == and !=");
+		this.println(" ------------------------");
+		i = 10;
+		this.println(" Print 10");
+		this.print(" ");
+		while(i == 10) { 
+			printInt(i); 
+			this.print(" "); 
+			i = i+1;
+		}
+		this.println(""); this.println("");
+		
+		i = 10;
+		this.println(" Print 10..1");
+		this.print(" ");
+		while(i != 0) { 
+			printInt(i); 
+			this.print(" "); 
+			i = i-1;
+		}
+		this.println(""); this.println("");
+			
+		this.println(" ------------------------");
+		this.println(" -> test < and >");
+		this.println(" ------------------------");
+		i = 0;
+		this.println(" Print 0..9");
+		this.print(" ");
+		while(i < 10) { 
+			printInt(i); 
+			this.print(" "); 
+			i = i+1;
+		}
+		this.println(""); this.println("");
+		
+		i = 10;
+		this.println(" Print 10..1");
+		this.print(" ");
+		while(i > 0) { 
+			printInt(i); 
+			this.print(" "); 
+			i = i-1;
+		}
+		this.println(""); this.println("");
+		
+		this.println(" ------------------------");
+		this.println(" -> test <= and =>");
+		this.println(" ------------------------");
+	  i = 0;
+		this.println(" Print 0..10");
+		this.print(" ");
+		while(i <= 10) { 
+			printInt(i); 
+			this.print(" "); 
+			i = i+1;
+		}
+		this.println(""); this.println("");
+	
+		i = 10;
+		this.println(" Print 10..0");
+		this.print(" ");
+		while(i >= 0) { 
+			printInt(i); 
+			this.print(" "); 
+			i = i-1;
+		}
+		this.println(""); this.println("");
+		
+		this.println(" ------------------------");
+		this.println(" -> test !== and !!=");
+		this.println(" ------------------------");
+		i = 20;
+		this.println(" Print 20..11");
+		this.print(" ");
+		while(!(i == 10)) { 
+			printInt(i); 
+			this.print(" "); 
+			i = i-1;
+		}
+		this.println(""); this.println("");
+		
+		i = 0;
+		this.println(" Print 0");
+		this.print(" ");
+		while(!(i != 0)) { 
+			printInt(i); 
+			this.print(" "); 
+			i = i+1;
+		}
+		this.println(""); this.println("");
+	
+		
+		this.println(" ------------------------");
+		this.println(" -> test !< and !>");
+		this.println(" ------------------------");
+		i = 20;
+		this.println(" Print 20..10");
+		this.print(" ");
+		while(!(i < 10)) { 
+			printInt(i); 
+			this.print(" "); 
+			i = i-1;
+		}
+		this.println(""); this.println("");
+		
+		i = -10;
+		this.println(" Print -10..0");
+		this.print(" ");
+		while(!(i > 0)) { 
+			printInt(i); 
+			this.print(" "); 
+			i = i+1;
+		}
+		this.println(""); this.println("");
+		
+		this.println(" ------------------------");
+		this.println(" -> test !<= and !>=");
+		this.println(" ------------------------");
+	  i = 20;
+		this.println(" Print 20..11");
+		this.print(" ");
+		while(!(i <= 10)) { 
+			printInt(i); 
+			this.print(" "); 
+			i = i-1;
+		}
+		this.println(""); this.println("");
+	
+		i = -10;
+		this.println(" Print -10..-1");
+		this.print(" ");
+		while(!(i >= 0)) { 
+			printInt(i); 
+			this.print(" "); 
+			i = i+1;
+		}
+		this.println(""); this.println("");
+
+	}
+	
+	Null main() {
+		this.println("*************************");
+		this.println("*** Play with Compop  ***");
+		this.println("*************************");	
+		this.test();
+	}
+
+
+}
+
+class Test {
+	Int a;
+}
+
+
+{
+	new Names().main();
+	printChar(10);
+	new Reals().main();
+	printChar(10);
+	new Compop().main();
+}
\ No newline at end of file
diff --git a/unittest.py b/unittest.py
index 2e4cd7a..5efad9e 100644
--- a/unittest.py
+++ b/unittest.py
@@ -6,8 +6,8 @@
 #
 #~iclamp/soft/bin/risc-emu
 COMPILER = "scala -cp classes zweic.GeneratorTest"
-RISC = "java -cp risc/lib/risc.jar risc.emulator.Main"
-#RISC = "/home/iclamp/soft/bin/risc-emu"
+#RISC = "java -cp risc/lib/risc.jar risc.emulator.Main"
+RISC = "/home/iclamp/soft/bin/risc-emu"
 OUTDIR = "asm"
 TABBING = '30'