What is btparser?

btparser is a backtrace parser and analyzer, which works with
backtraces produced by the GNU Project Debugger. It can parse a text
file with a backtrace to a tree of C structures, allowing to analyze
the threads and frames of the backtrace and work with them.

btparser also contains some backtrace manipulation and extraction
routines:
- it can find a frame in the crash-time backtrace where the program
  most likely crashed (a chance is that the function described in that
  frame is buggy)
- it can produce a duplication hash of the backtrace, which helps to
  discover that two crash-time backtraces are duplicates, triggered by
  the same flaw of the code
- it can "rate" the backtrace quality, which depends on the number of
  frames with and without the function name known (missing function
  name is caused by missing debugging symbols)

== Speed measurement

For speed measurment the best backtrace is 547367.bt.
Valgrind is very useful to see where the time is spent:
$ valgrind --tool=callgrind btparser 547367.bt
$ kcachegrind callgrind.out.11555

=== Do not use regexps!
$ time btparser --debug 547367.bt

With single regexp in btp_frame_parse_file_location:
real	5m41.857s
user	5m29.894s
sys	0m0.573s

Without it:
real	0m7.753s
user	0m0.761s
sys	0m0.173s