Memory problem when returning address of local variable

[wdeconinck]

A worrying warning for following code in parms_map.c

int *parms_MapGlobalToLocal(parms_Map self, int gindex)
{
  int *lindex;
  
  if(self->isserial)
     lindex = &gindex;
  else
     lindex = parms_TableGet(self->table, gindex);
  
  return lindex;
}

The warning is:

/perm/nawd/fesom2/lib/parms/src/parms_map.c: In function ‘parms_MapGlobalToLocal’:
/perm/nawd/fesom2/lib/parms/src/parms_map.c:744:10: warning: function may return address of local variable [-Wreturn-local-addr]
   return lindex;
          ^~~~~~
/perm/nawd/fesom2/lib/parms/src/parms_map.c:735:49: note: declared here
 int *parms_MapGlobalToLocal(parms_Map self, int gindex)
                                             ~~~~^~~~~~

This happens in the assignment of the pointerlindex to &gindex in the first part of the if statement is problematic, as gindex is a temporary in this function.