diff --git a/src/main/java/de/dhbwstuttgart/bytecode/Codegen.java b/src/main/java/de/dhbwstuttgart/bytecode/Codegen.java
index 70810cbd6..d32aa8513 100644
--- a/src/main/java/de/dhbwstuttgart/bytecode/Codegen.java
+++ b/src/main/java/de/dhbwstuttgart/bytecode/Codegen.java
@@ -949,7 +949,7 @@ public class Codegen {
                 mv.visitMethodInsn(call.isInterface() ? INVOKEINTERFACE : call.isStatic() ? INVOKESTATIC: call.name().equals("<init>") ? INVOKESPECIAL : INVOKEVIRTUAL,
                         call.owner().getInternalName(), call.name(), descriptor, call.isInterface());
 
-                if (call.returnType() != null && !(call.returnType() instanceof TargetPrimitiveType)) {
+                if (call.type() != null && call.returnType() != null && !(call.returnType() instanceof TargetPrimitiveType)) {
                     if (!call.returnType().equals(call.type()) && !(call.type() instanceof TargetGenericType))
                         mv.visitTypeInsn(CHECKCAST, call.type().getInternalName());
                     unboxPrimitive(state, call.type());
diff --git a/src/main/java/de/dhbwstuttgart/target/generate/ASTToTargetAST.java b/src/main/java/de/dhbwstuttgart/target/generate/ASTToTargetAST.java
index fbe9ce756..d82d658d5 100644
--- a/src/main/java/de/dhbwstuttgart/target/generate/ASTToTargetAST.java
+++ b/src/main/java/de/dhbwstuttgart/target/generate/ASTToTargetAST.java
@@ -575,16 +575,22 @@ public class ASTToTargetAST {
         private void findChain(Set<TypePlaceholder> referenced, Set<ResultPair<?, ?>> input, Set<ResultPair<?, ?>> output, TypePlaceholder start, TypePlaceholder end, Set<TypePlaceholder> chain) {
             if (referenced.contains(end)) {
                 var pair = new PairTPHsmallerTPH(start, end);
-                if (input.contains(pair)) output.add(pair);
+                output.add(pair);
+                return;
             }
+            var foundNext = false;
             for (var pair : input) {
                 if (pair instanceof PairTPHsmallerTPH ptph && ptph.left.equals(end)) {
                     if (chain.contains(ptph.right)) return;
                     chain = new HashSet<>(chain);
                     chain.add(ptph.right);
                     findChain(referenced, input, output, start, ptph.right, chain);
+                    foundNext = true;
                 }
             }
+            if (!foundNext) {
+                output.add(new PairTPHequalRefTypeOrWildcardType(start, OBJECT));
+            }
         }
 
         void eliminateInnerTypeVariables(Set<TypePlaceholder> referenced, Set<ResultPair<?, ?>> input) {
@@ -594,7 +600,6 @@ public class ASTToTargetAST {
                     if (pair instanceof PairTPHsmallerTPH pthp && pthp.left.equals(tph)) {
                         var chain = new HashSet<TypePlaceholder>();
                         chain.add(tph);
-                        chain.add(pthp.right);
                         findChain(referenced, input, output, tph, pthp.right, chain);
                     }
                 }