[SOLVED] Interpreter hiccup

[lars.saalbach]

Good morning,

 

I got a very strange behavior with the attached sample:

 

We have two different classes:

 

- "RootContainer" (Sub: ContainerGroup)

- "RootWidget" (Sub: Label)

 

Both of them inherit the function "getParent".

 

In setElementAndValidate(...) we pass an created class and calling: "_parent.getParent()"

 

If the passed object is an instance of "RootContainer" we can call getParent(), if object is an instance of "RootWidget" the interpreter has some troubles: 

 

typeof(_parent): GUI::QB::ContainerRoot

Name: containergroup

typeof(_parent): GUI::QB::ContainerGroup

Name: label

Machine::do_callucfv(): "GUI::QB::Label 0x7f1e82d83800 (196613:0:0)" is not a suitable user class

Stack dump:

0x0000: GUI::QB::Label 0x7f1e82d83800 (196613:0:0)

Call stack:

00: 0x00000618 setElementAndValidate()

01: 0x0000066d init()

Disassemble:

0x0000063f: callucfv   ContainerRoot.getParent 0x00000571

0x00000643: popucx     ContainerRoot

0x00000645: popv       parent

 

 

If we change the parameter type from "ContainerGroup _parent" to "void", "Widget" or "int" the interpreter is crashing now at "RootContainer" as well.

If we check the class type with "typeof" and cast  _parent to the specific class, its working.

For me it seems like a bug in the interpreter that causes a wrong detection of the instance type.

 

The expected behavior should be that the instance is correctly detected and code execution continues.

Greetings

 

sample.tar.gz

[necris]

Hello, Lars

We can't cast _parent without specific class declaration.
"void", "Widget" or "int" types don't have getParent() method.

And when you call getParent() you need explicit declaration of it's type:

parent = GUI::QB::Label(_parent).getParent();
parent = GUI::QB::ContainerRoot(_parent).getParent();
...

Or you can use is_base_class


You can also use proposed tip from Tips and tricks : "Interface class support and virtual function declaration"

[lars.saalbach]

Hello Necris,

 

i'm gonna check it with the Tip and tricks section :)

 

Thanks so far!

[lars.saalbach]

Update:
With multiple inheritance this problem was solved.

Thanks for this tip :)
Greetings

Lars