Debugger: std::vector not properly shown when using GDB system pretty printers

When using system GDB pretty printers (i.e. the "Load system gdb pretty printers" checkbox in "Tools" -> "Options" -> "Debugger" -> "GDB" is enabled), vectors are not properly displayed in the debugger view when expanded.

Steps to reproduce:

1) Use the sample program from below and set a breakpoint at the line where the output is done.

2) Start debugging with GDB and system GDB pretty printers enabled.

3) Observe that the "Locals" view initially shows the value "std::vector of length 2, capacity 2" for the local variable "someVector" and a small arrow key to expand (as expected).

4) toggle the expansion, so that the value is expanded

Result:

• the value "<not accessible>" is now shown for "someVector"
• Only a single subelement/child with name "[0]" is shown and no value is displayed for it

Expected result:

• the displayed value for "someVector" remains unchanged
• both elements in the vector are shown with their respective values (23, 44)

Small sample program:

#include <iostream>
#include <vector>

int main()
{
    std::vector<int> someVector;
    someVector.push_back(23);
    someVector.push_back(44);
    std::cout << "Hello world!" << std::endl;
    return 0;
}