Thank you Ian, the mystery is now entirely solved :) 2010/9/8 Ian Lance Taylor <iant@google.com>: > > Joel <torpe@laposte.net> writes: > >> One part of the mystery is now solved, it remains the last part: what >> about the $L0 label? > > There is no $L0 label. Label numbers start at 1. See the label_num > variable in emit-rtl.c. > > Ian > >