Debugger, watch variables not accessible and 'this' not available

 
I'm using and working on RedHat Linux:

uname -a
Linux new-host 3.10.0-514.el7.x86_64 #1 SMP Wed Oct 19 11:24:13 EDT 2016 x86_64 x86_64 x86_64 GNU/Linux

cat /etc/redhat-release
Red Hat Enterprise Linux Workstation release 7.2 (Maipo)

gcc --version
gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-11)
Copyright (C) 2015 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

gdb --version
GNU gdb (GDB) Red Hat Enterprise Linux 7.6.1-94.el7
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later http://gnu.org/licenses/gpl.html
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-redhat-linux-gnu".
For bug reporting instructions, please see:
http://www.gnu.org/software/gdb/bugs/.

I have been using and developing with Qt since January 2016, up until about a month ago the debugger was fully functional, however I think due to an update it has become less useful and functionality has been lost.  'this' is very often not accessible and one particular object which is derived from QObject is never accessible and when expanded in the watch window just displays [0].
 
We desperately need a resolution to this as for several weeks now the debugger is not useful and progress has ground to an almost stand still.

On another system that has the same version of the IDE and RedHat we don't have this problem, its running the exact same source code but has none of the issues, the only difference is that the system that is working has not been updated in terms of the operating system, so its quite possible there is a conflicting library that is causing this behaviour?