- This to fix MDEV-7498. All changes made to AllocateValue to be sure that

the sp and p variable be initialised failed. Not understanding what causes
  this valgrind warning, I finally changed the way Mulval is allocated just
  to avoid it. This is a BAD solution as it does not really fix the problem
  but just hide it. This will have to be re-considered.
modified:
  storage/connect/tabjson.cpp
  storage/connect/value.cpp

storage/connect/tabjson.cpp

@@ -507,7 +507,15 @@ bool JSONCOL::ParseJpath(PGLOBAL g)
 
   if (Parsed)
     return false;                       // Already done
-  else if (InitValue(g))
+    
+  if (InitValue(g))
+    return true;
+  else
+    MulVal = Value;
+    
+  Value = NULL;
+    
+  if (InitValue(g))
     return true;
   else if (!Jpath)
     Jpath = Name;
@@ -540,7 +548,6 @@ bool JSONCOL::ParseJpath(PGLOBAL g)
 
     } // endfor i, p
 
-  MulVal = AllocateValue(g, Value);
   Parsed = true;
   return false;
   } // end of ParseJpath

storage/connect/value.cpp

@@ -436,6 +436,9 @@ PVAL AllocateValue(PGLOBAL g, PVAL valp, int newtype, int uns)
   bool un = (uns < 0) ? false : (uns > 0) ? true : valp->IsUnsigned();
   PVAL vp;
 
+  if (!valp)
+    return NULL;
+    
   if (newtype == TYPE_VOID)  // Means allocate a value of the same type
     newtype = valp->GetType();
 
@@ -443,13 +446,8 @@ PVAL AllocateValue(PGLOBAL g, PVAL valp, int newtype, int uns)
     case TYPE_STRING:
       p = (PSZ)PlugSubAlloc(g, NULL, 1 + valp->GetValLen());
 
-      if ((sp = valp->GetCharString(p)) != p) {
-        if (sp)
-          strcpy (p, sp);
-        else
-          *p = 0;
-
-        } // endif sp
+      if ((sp = valp->GetCharString(p)) != p)
+        strcpy(p, sp);
 
       vp = new(g) TYPVAL<PSZ>(g, p, valp->GetValLen(), valp->GetValPrec());
       break;