[MacRuby-devel] [MacRuby] #615: macruby segfaults when generating large random numbers

[MacRuby]

#615: macruby segfaults when generating large random numbers
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 Reporter:  ahobson@…          |       Owner:  lsansonetti@…        
     Type:  defect             |      Status:  new                  
 Priority:  major              |   Milestone:                       
Component:  MacRuby            |    Keywords:  rand bignum          
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Comment(by ahobson@…):

 I just noticed that assigning to a variable seems to affect the behavior
 if I generate a smaller number.
 {{{
 # notice no crash!
 % macruby -e 'x=rand(2**1024)'

 # but this does crash
 % macruby -e 'x=rand(2**1024);puts x'
 unknown: [BUG] Segmentation fault
 MacRuby version 0.6 (ruby 1.9.0) [universal-darwin10.0, x86_64]

 zsh: abort      macruby -e 'x=rand(2**1024);puts x'

 # maybe we just got lucky before?
 % macruby -e 'x=rand(2**1024)'
 % macruby -e 'x=rand(2**1024)'
 % macruby -e 'x=rand(2**1024)'

 # doesn't seem like it.  But generating a larger random number always
 seems to crash
 % macruby -e 'x=rand(2**2048)'
 unknown: [BUG] Segmentation fault
 MacRuby version 0.6 (ruby 1.9.0) [universal-darwin10.0, x86_64]

 zsh: abort      macruby -e 'x=rand(2**2048)'
 % macruby -e 'x=rand(2**2048)'
 unknown: [BUG] Segmentation fault
 MacRuby version 0.6 (ruby 1.9.0) [universal-darwin10.0, x86_64]

 zsh: abort      macruby -e 'x=rand(2**2048)'

 # hmm, where does the problem seem to occur between 1024 and 2048?
 # 2**1472 seems to be reliably ok
 % macruby -e 'x=rand(2**1472)'
 % macruby -e 'x=rand(2**1472)'
 % macruby -e 'x=rand(2**1472)'

 # but 2**1473 seems to reliably crash
 % macruby -e 'x=rand(2**1473)'
 unknown: [BUG] Segmentation fault
 MacRuby version 0.6 (ruby 1.9.0) [universal-darwin10.0, x86_64]

 zsh: abort      macruby -e 'x=rand(2**1473)'

 }}}

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Ticket URL: <http://www.macruby.org/trac/ticket/615#comment:3>
MacRuby <http://macruby.org/>