rubinius

I'm encountering some pretty severe instability attempting to use MVM. After creating a new VM, attempting to perform any sort of operations on the VM object crashes Rubinius. I've encountered this on both Linux 2.6 and MacOS X 10.5.

I've encountered multiple different behaviors, and the one that occurs seems to be completely sporadic. Those behaviors are:

1) Complete VM crash. Examples:

Linux:

irb(main):001:0> vm = Rubinius::VM.spawn

=> # @stdout=# @stderr=#>

irb(main):002:0> Rubinius::VM.send_message(2, 'hi')

An error has occured: Segmentation fault (SIGSEGV) (11)

Ruby backtrace:

0xb742c884 #perform_readline+73 in readline.c:0

0xb742c814 Class#readline+40 in /home/tony/rbx/lib/readline.rb:10

0xb742c7a8 IRB::ReadlineInputMethod#gets+12 in /home/tony/rbx/lib/irb/input-method.rb:97

0xb742c73c #+7 in /home/tony/rbx/lib/irb.rb:138

0xb742c6cc IRB::Irb#signal_status+34 in /home/tony/rbx/lib/irb.rb:269

0xb742c674 #+20 in /home/tony/rbx/lib/irb.rb:137

0xb742c608 Proc#call+22 in kernel/core/proc.rb:84

0xb7429ec4 RubyLex#buf_input+13 in /home/tony/rbx/lib/irb/ruby-lex.rb:189

0xb7429e58 RubyLex#getc+14 in /home/tony/rbx/lib/irb/ruby-lex.rb:104

0xb7429dd8 IRB::SLex::Node#match_io+33 in /home/tony/rbx/lib/irb/slex.rb:206

0xb7429d64 IRB::SLex#match+68 in /home/tony/rbx/lib/irb/slex.rb:74

0xb7429cf8 RubyLex#token+24 in /home/tony/rbx/lib/irb/ruby-lex.rb:287

0xb7429c88 RubyLex#lex+10 in /home/tony/rbx/lib/irb/ruby-lex.rb:263

0xb740761c #+16 in /home/tony/rbx/lib/irb/ruby-lex.rb:234

0xb74075c4 #+4 in kernel/core/throw_catch.rb:63

0xb7407554 Class#register+57 in kernel/core/throw_catch.rb:46

0xb74074e0 Kernel#catch+24 in kernel/core/throw_catch.rb:62

0xb7404d44 RubyLex#each_top_level_statement+28 in /home/tony/rbx/lib/irb/ruby-lex.rb:229

0xb7404cd8 IRB::IrbRubinius#process_statements+19 in /home/tony/rbx/lib/irb/rubinius.rb:4

0xb7404c6c IRB::Irb#eval_input+88 in /home/tony/rbx/lib/irb.rb:152

0xb7404c14 #+5 in /home/tony/rbx/lib/irb.rb:76

0xb7404bbc #+4 in kernel/core/throw_catch.rb:63

0xb7404b4c Class#register+57 in kernel/core/throw_catch.rb:46

0xb7404ad8 Kernel#catch+24 in kernel/core/throw_catch.rb:62

0xb78cb6f0 Class#start+209 in /home/tony/rbx/lib/irb.rb:75

0xb78cbd34 #__script__+28 in /home/tony/rbx/lib/bin/irb.rb:13

0xb78cc2a0 CompiledMethod#as_script+80 in kernel/core/compiled_method.rb:210

0xb78cc7d4 Class#single_load+466 in kernel/core/compile.rb:235

0xb78ccdfc #+320 in kernel/core/compile.rb:149

0xb78cd2d0 Array#each+25 in kernel/core/array.rb:573

0xb78cd358 Class#unified_load+189 in kernel/core/compile.rb:120

0xb78cd3b0 Kernel#require+193 in kernel/core/compile.rb:449

0xb78c8730 #__script__+1447 in kernel/loader.rb:225

VM Registers:

IP: 0073

SP: 0236

Exception: none

OS X:

irb(main):001:0> vm = Rubinius::VM.spawn

=> # @stdout=# @stderr=#>

irb(main):002:0> Rubinius::VM.send_message(2, 'hi')

Trace/BPT trap

The same exception occurs if I pass the VM object to Rubinius::VM.send_message, although I don't believe that's the correct usage.

However, even more trivial things seem to crash it (on both Linux and OS X):

irb(main):001:0> vm = Rubinius::VM.spawn

=> # @stdout=# @stderr=#>

irb(main):002:0> vm.object_id

Trace/BPT trap

Rubinius::VM#inspect is the only method I'm aware of that doesn't instantly crash the VM.

2) VM stuck in an infinite loop?

I've experienced this behavior on OS X exclusively, but sometimes, repeating the same examples above, the VM appears to go into an infinite loop, e.g.:

irb(main):001:0> vm = Rubinius::VM.spawn

=> # @stdout=# @stderr=#>

irb(main):002:0> Rubinius::VM.send_message(2, 'hi')

(... hangs forever ...)

3) It works?

For whatever reason, this usage doesn't immediately crash the VM on either OS X or Linux:

irb(main):001:0> p Rubinius::VM.spawn; Rubinius::VM.send_message 2, 'hi'

# @stdout=# @stderr=#>

=> true

irb(main):002:0>

However, it appears attempting to do anything after making this call crashes the VM:

irb(main):001:0> p Rubinius::VM.spawn; Rubinius::VM.send_message 2, 'hi'

# @stdout=# @stderr=#>

=> true

irb(main):002:0> puts 'hi'

An error has occured: Segmentation fault (SIGSEGV) (11)

Ruby backtrace:

0xb73c62d8 #perform_readline+73 in readline.c:0

0xb73c6268 Class#readline+40 in /home/tony/rbx/lib/readline.rb:10

0xb73c61fc IRB::ReadlineInputMethod#gets+12 in /home/tony/rbx/lib/irb/input-method.rb:97