I came across the diamond problem and found different solutions for different cases with a single diamond. However I couldn't find a solution for 'chained' diamonds.

According to the structure: yes, I want to have multiple baseclasses everytime, so virtual inheritance isn't a solution (is it even called diamond then?). I also wanted to avoid get/set-functions for every middle-layer of a diamond.

p   p
|   |
k   k
 \ /
  s

class parent { int val; };
class kid1 : public parent {};
class kid2 : public parent {};
class school : public kid1, public kid2 {};

Accessing val in the parent class works now like follows:

school* s = new school;
s->kid1::val=1; // works

But what about the next 'chained' diamond:

p   p   p   p
|   |   |   |
k   k   k   k
 \ /     \ /
  s       s
  |       |
  c       c
    \   /
      w

class country1 : public school {};
class country2 : public school {};
class world : public country1, public country2 {};

Accessing val via:

world* w = new world;
w->country1::kid1::val=1; // error

results in: 

error: ‘kid1’ is an ambiguous base of ‘world’

Why? Isn't the route to the value well defined?

c++ inheritance diamond-problem
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