Bug #6009
closed
Rapid signal delivery via kill(2) causes SystemStackError
Description
=begin
Running the following program with a trivial signal handler can crash with a SystemStackError if signals are delivered rapidly:
$ ruby -ve 'p Process.pid; trap "USR1" do 10 ** 100; end; sleep'
ruby 2.0.0dev (2012-02-11 trunk 34547) [x86_64-darwin11.2.0]
4504
-e: SystemStackError
In a separate terminal:
ruby -e 'loop do Process.kill "USR1", 4504 end'
As each signal is delivered, ruby interrupts the current signal handler to perform the newly arrived one and quickly runs out of stack.
With an empty system handler the SystemStackError takes slightly longer to occur.
This also occurs with 1.9.3-p0:
$ ~/.multiruby/install/1.9.3-p0/bin/ruby -ve 'p Process.pid; trap "USR1" do 10 ** 100; end; sleep'
ruby 1.9.3p0 (2011-10-30 revision 33570) [x86_64-darwin11.2.0]
4529
-e: SystemStackError
and with ruby-1.9.2-p290:
$ ~/.multiruby/install/1.9.2-p290/bin/ruby -ve 'p Process.pid; trap "USR1" do 10 ** 100; end; sleep'
ruby 1.9.2p290 (2011-07-09 revision 32553) [x86_64-darwin11.2.0]
4534
ruby-1.8.7-p330 exits with a zero exit code:
$ ~/.multiruby/install/1.8.7-p330/bin/ruby -ve 'p Process.pid; trap "USR1" do 10 ** 100; end; sleep'
ruby 1.8.7 (2010-12-23 patchlevel 330) [i686-darwin11.2.0]
4564
$ echo $?
0
=end
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