If a variable can be NULL in one place, it can be NULL later on as well. Found by Coverity.
If a variable can be NULL in one place, it can be NULL later on as
well.
Found by Coverity.

zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb