Amend console stack fixes to work with gcc in Ubuntu x64.

Engine/source/console/console.cpp

@@ -1758,7 +1758,7 @@ const char *ConsoleValue::getStringValue()
    if(type == TypeInternalString || type == TypeInternalStackString)
       return sval;
    else if (type == TypeInternalStringStackPtr)
-      return STR.mBuffer + (U32)sval;
+      return STR.mBuffer + (uintptr_t)sval;
    if(type == TypeInternalFloat)
       return Con::getData(TypeF32, &fval, 0);
    else if(type == TypeInternalInt)
@@ -1770,9 +1770,9 @@ const char *ConsoleValue::getStringValue()
 StringStackPtr ConsoleValue::getStringStackPtr()
 {
    if (type == TypeInternalStringStackPtr)
-      return (U32)sval;
+      return (uintptr_t)sval;
    else
-      return (U32)-1;
+      return (uintptr_t)-1;
 }
 
 bool ConsoleValue::getBoolValue()

Engine/source/console/simEvents.cpp

@@ -129,7 +129,7 @@ ConsoleValueRef SimConsoleThreadExecCallback::waitForResult()
       return retVal;
    }
 
-   return NULL;
+   return (const char*)NULL;
 }
 
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