post_mortem: to test $! *before* running debug_at_ext or else we may get an erroneous message:   ruby-debug-base.rb:162:in `current_context': Debugger.start is not called yet. (RuntimeError)
post_mortem: to test $! *before* running debug_at_ext or else we may get an erroneous message:
  ruby-debug-base.rb:162:in `current_context': Debugger.start is not called yet. (RuntimeError)

A simple test case to show the problem:

"require rubygems"
"require ruby-debug"
Debugger.start
Debugger.post_mortem
exit   # Causes us to incorrectly give the above error


denofevil/ruby-debug,denofevil/ruby-debug,denofevil/ruby-debug