gagalago/latexila — comment on commit c18a7b939cc637d93afe8b66a1a7b1bb53cd8d00
File: src/completion.vala line 868
By swilmet:

Vala already ensure that cmd_name is not null. If you want to be able to call the function with cmd_name as null, you must add a "?":
string? cmd_name