Found and fixed a memory leak in the rope strings

Also fixed a bit manipulation error in the GC.

source/toy_bucket.c

@@ -88,7 +88,7 @@ TOY_API void Toy_collectBucketGarbage(Toy_Bucket** bucketHandle) {
 				gc = false;
 				break;
 			}
-			ptr += (*((int*)(ptr)) ^ 1) + 4; //XOR to remove the 'free' flag from the size
+			ptr += ((*((int*)ptr) | 1) ^ 1) + 4; //OR + XOR to remove the 'free' flag from the size
 		}
 
 		//free this link, if its been entirely released

source/toy_scope.c

@@ -193,6 +193,8 @@ void Toy_assignScope(Toy_Scope* scope, Toy_String* key, Toy_Value value) {
 		return;
 	}
 
+	Toy_freeValue(entryPtr->value);
+
 	entryPtr->value = value;
 }
 

source/toy_string.c

@@ -20,10 +20,18 @@ static void incrementRefCount(Toy_String* str) {
 static void decrementRefCount(Toy_String* str) {
 	str->info.refCount--;
 	if (str->info.type == TOY_STRING_NODE) {
+		//the parent of this node triggered a decrement across the whole tree
 		decrementRefCount(str->node.left);
 		decrementRefCount(str->node.right);
 	}
 	if (str->info.refCount == 0) {
+		if (str->info.type == TOY_STRING_NODE) {
+			//THIS node has triggered the decrement, so run this again
+			decrementRefCount(str->node.left);
+			decrementRefCount(str->node.right);
+		}
+
+		//mark this memory as unused
 		Toy_releaseBucketPartition((void*)str);
 	}
 }

source/toy_vm.c

@@ -210,7 +210,7 @@ static void processAssign(Toy_VM* vm) {
 	Toy_Value name = Toy_popStack(&vm->stack);
 
 	//assign it
-	Toy_assignScope(vm->scope, TOY_VALUE_AS_STRING(name), Toy_copyValue(&vm->memoryBucket, value)); //scope now owns the value, doesn't need to be freed
+	Toy_assignScope(vm->scope, TOY_VALUE_AS_STRING(name), Toy_copyValue(&vm->memoryBucket, value));
 
 	//in case of chaining, leave a copy on the stack
 	bool chainedAssignment = READ_BYTE(vm);
@@ -220,6 +220,7 @@ static void processAssign(Toy_VM* vm) {
 
 	//cleanup
 	Toy_freeValue(name);
+	Toy_freeValue(value);
 }
 
 static void processAssignCompound(Toy_VM* vm) {