Hi, the following sample script leads to a crash of gretl using the latest git version under Ubuntu 19.04. The terminal message is as follows: <[1] 3306 segmentation fault (core dumped)> Interestingly, the crash does not happen in case of <b.ALL += b.A> that's when only a single list is passed to b.ALL. <hansl> clear set verbose off open denmark.gdt -q # Add series to a list using the wildcard operator list ALL = null list L = LRM LRY ALL += L # Works ALL # Make use of bundle elements (list) function void somefun (bundle *b) list b.ALL = null list b.A = null list b.B = null end function bundle b = null somefun(&b) b.A += L # works eval b.A b.B += IBO eval b.B # Crash b.ALL += b.A b.B # Crash in case at least 2 lists are passed! eval b.ALL </hansl> Thanks, Artur