http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54761
--- Comment #4 from Uros Bizjak <ubizjak at gmail dot com> 2012-10-01 12:11:16 UTC --- For some reason _Unwind_Backtrace does not unwind after backtrace_full/backtrace.c. This is problem in alpha unwinder.