base, sim: Add missing destructors

Derived classes with virtual functions need to define a virtual
destructor or a protected destructor otherwise calling the base class
destructor has undefined behavior. This change adds a virtual
distructor in the base class.

Change-Id: I1c855aa56dff6585ff99b9147bdb4eb9729a0a53
Signed-off-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/14815
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

src/base/statistics.hh

@@ -2090,6 +2090,8 @@ class Node
      *
      */
     virtual std::string str() const = 0;
+
+    virtual ~Node() {};
 };
 
 /** Shared pointer to a function Node. */

src/cpu/minor/buffers.hh

@@ -381,6 +381,8 @@ class Reservable
 
     /** Free a reserved slot */
     virtual void freeReservation() = 0;
+
+    virtual ~Reservable() {};
 };
 
 /** Wrapper for a queue type to act as a pipeline stage input queue.
@@ -418,8 +420,6 @@ class Queue : public Named, public Reservable
         dataName(data_name)
     { }
 
-    virtual ~Queue() { }
-
   public:
     /** Push an element into the buffer if it isn't a bubble.  Bubbles are
      *  just discarded.  It is assummed that any push into a queue with

src/cpu/testers/traffic_gen/stream_gen.hh

@@ -63,6 +63,8 @@ class StreamGen
     }
 
   public:
+    virtual ~StreamGen() {};
+
     virtual uint32_t pickStreamID() = 0;
     virtual uint32_t pickSubStreamID() = 0;
 

src/mem/qos/q_policy.hh

@@ -99,6 +99,8 @@ class QueuePolicy
      */
     void setMemCtrl(MemCtrl* mem) { memCtrl = mem; };
 
+    virtual ~QueuePolicy() {};
+
   protected:
     QueuePolicy(const QoSMemCtrlParams* p)
       : memCtrl(nullptr)

src/sim/faults.hh

@@ -47,6 +47,8 @@ class FaultBase
     virtual FaultName name() const = 0;
     virtual void invoke(ThreadContext * tc, const StaticInstPtr &inst =
                         StaticInst::nullStaticInstPtr);
+
+    virtual ~FaultBase() {};
 };
 
 class UnimpFault : public FaultBase