knownConditionTrueFalse - callback-driven event-loop flag considered constant

[Long Huang]

Reproduction

#include <cassert>

class EventLoop
{
public:
   static void ProcessEvents();
};

class Listener
{
public:
   bool Start()
   {
      Waiting = true;
      for(int remaining = 2; remaining > 0 && Waiting; --remaining)
      {
         EventLoop::ProcessEvents();
      }
      return !Waiting;
   }

   void Ready() { Waiting = false; }

private:
   bool Waiting = false;
};

Listener* ActiveListener = nullptr;

void EventLoop::ProcessEvents()
{
   ActiveListener->Ready();
}

int main()
{
   Listener listener;
   ActiveListener = &listener;
   const bool started = listener.Start();
   assert(started);
}

Expected:

Neither condition is constant, dispatch calls Ready() and changes
the member before the next iteration.

Actual:

scratch_outer_eventloop.cpp:15:47: warning: Condition 'Waiting' is always true [knownConditionTrueFalse]
scratch_outer_eventloop.cpp:19:14: warning: Return value '!Waiting' is always false [knownConditionTrueFalse]

[CHR]

Looks like a variation of Looks like a variation of https://trac.cppcheck.net/ticket/11562