connect engine: correct two uninitalized variable errors

storage/connect/tabxml.cpp:1616:46: warning: ‘*this.XMLCOL::Long’ may be used uninitialized [-Wmaybe-uninitialized]
 1616 |   Valbuf = (char*)PlugSubAlloc(g, NULL, n * (Long + 1));

In this case we are overriding the class 3 lines earlier. Add
some constructs to preserve the value of Long as the old class
being replaced with a new subclass.

storage/connect/filter.cpp:1594:13: warning: ‘*this.FILTERCMP::FILTERX.FILTERX::FILTER.FILTER::Opc’ is used uninitialized [-Wuninitialized]
 1594 |   Bt = OpBmp(g, Opc);
The construction of FILTERCMP has an Opc(ode) and this should be passed
rather than relying on the uninitialized value of the parent class.

Also save its value in the class.

Author: grooverdan

storage/connect/filter.cpp

@@ -1179,7 +1179,7 @@ bool FILTER::Convert(PGLOBAL g, bool having)
       case OP_GT:
       case OP_GE:
       case OP_LT:
-      case OP_LE:  new(this) FILTERCMP(g); break;
+      case OP_LE:  new(this) FILTERCMP(g, Opc); break;
       case OP_AND: new(this) FILTERAND; break;
       case OP_OR:  new(this) FILTEROR;  break;
       case OP_NOT: new(this) FILTERNOT; break;
@@ -1589,8 +1589,9 @@ void FILTER::Prints(PGLOBAL g, char *ps, uint z)
 /***********************************************************************/
 /*  FILTERCMP constructor.                                             */
 /***********************************************************************/
-FILTERCMP::FILTERCMP(PGLOBAL g)
+FILTERCMP::FILTERCMP(PGLOBAL g, OPVAL Opc)
   {
+  this->Opc= Opc;
   Bt = OpBmp(g, Opc);
   } // end of FILTERCMP constructor
 

storage/connect/filter.h

@@ -120,7 +120,7 @@ class FILTERX : public FILTER {
 class FILTERCMP : public FILTERX {
  public:
   // Constructor
-  FILTERCMP(PGLOBAL g);
+  FILTERCMP(PGLOBAL, OPVAL);
 
   // Methods
   bool Eval(PGLOBAL) override;

storage/connect/tabxml.cpp

@@ -1611,7 +1611,9 @@ bool XMLCOL::ParseXpath(PGLOBAL g, bool mode)
     if (Tdbp->Xpand)
       n = Tdbp->Limit;
 
+    auto oLong = Long;
     new(this) XMULCOL(Value);        // Change the class of this column
+    Long = oLong;
     } // endif Inod
 
   Valbuf = (char*)PlugSubAlloc(g, NULL, n * (Long + 1));