Some Variables Cannot be expanded

Specs:

GDB 8.3
CXX_FLAGS (for debug builds): -g -O0
~/.gdbinit:
set pretty print on
set print elements 0

Details:
When using the PImpl pattern with std::unique_ptr or std::shared_ptr to store the PImpl member, sometimes the values of the PImpl member cannot be expanded in the Variables window beyond the get() method of the std::ptr.

Sometimes, adding an expression for the PImpl member (e.g. *obj.m_impl.get()) allows the values of the member to be viewed. Sometimes the members still cannot be viewed.

Printing the same expression (e.g. p *obj.m_impl.get()) from the gdb terminal (within Qt Creator) always displays the members of the value.

Sample code:

PImpl.hpp:

#define PIMPL(memberName) \
  struct Impl; \
  struct ImplDeleter { void operator()(Impl*); }; \
  std::unique_ptr<Impl, ImplDeleter memberName;

#define PIMPL_DELETER(class) \
  void class::ImplDeleter::operator()(class::Impl* toDelete) \
  { delete toDelete; }

ClassOne.hpp:

#include "PImpl.hpp"

class ClassOne
 {
 public:
     // Public interface
 private:
     PIMPL(m_impl);
 };

ClassOne.cpp:

#include "ClassOne.hpp"

struct ClassOne::Impl
 {
     // Private interface
     std::string aMember;
     static int AStaticMember = 4;
 };
 PIMPL_DELETER(ClassOne);

// Class One Public Interface Implementation}}

*ClassTwo.hpp:*

#include "PImpl.hpp"
 class ClassTwo
 {
 public:
     // Public interface 
 private:
     PIMPL(m_impl);
 };

ClassTwo.cpp:

#include "ClassTwo.hpp"
#include "ClassOne.hpp"

struct ClassTwo::Impl
 {
     ClassOne classOneMember;
   // Other members
 }
 PIMPL_DELETER(ClassTwo)

// Class Two Public interface implementation.

In this example, when debugging a program which constructs and manipulates a ClassOne object directly it is possible to see the values of ClassOne::m_impl from the Variables pane. When debugging a program which constructs an manipulates a ClassTwo object, the details of *ClassTwo::m_impl->classOneMember.m_impl.get() cannot be viewed in either the Variables or the Expressions pane, but they can be viewed in the GDB terminal.

If desired, I can provide screenshots of the behavior.