Debugger doesn't shows value of heap variables on mouse hover

Qt creator, the debugger is able to resolve stack variables and shows value when hovering mouse over them but does not resolves the value of heap variable, for instance class members only shows data type.
Though it is visible if class member varaibales are are expended in right side.
Also, in lambda function stack variable are not showing its values.

The lamba function test is a little better on windows:

• hover counter variable gives empty hover dialog (see lambda_windows.png)
• stack variables and values appear in the locals window
• hover the member variable shows the data type
• not possible to see the member values in the locals window

Compiler: gcc 5.4.0

• Debugger: gdb 7.11.1
• Qt 5.12 prebuilt by Qt
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