From: Howard Yeh <hayeah@...>
Date: 2009-09-19T01:53:57+09:00
Subject: [ruby-core:25634] Kernel.eval("local_variables",binding) bug in Ruby 1.9

Hi,

My ruby runtime is "ruby 1.9.1p0 (2009-01-30 revision 21907) [i686-
linux]"

Kernel eval works for these cases:

puts "2 times"
1.times do
�a = 1
�p Kernel.eval("local_variables",binding)
end

puts "while"
while true
�a = 1
�p Kernel.eval("local_variables",binding)
�break
end

puts "lambda"
lambda {
�a=1
�p Kernel.eval("local_variables",binding)
}.call


But I get a segfault with

for i in 1..100
�a = 1
�p Kernel.eval("local_variables",binding)
�break
end

But you can try,

for i in 1..100
�a = 1
�r = Kernel.eval("local_variables",binding)
�p r.length # => 4, but should be 3
�p r[1..-1] # => [:i,:a,:r]
�p r.first.class # => Symbol
�p r.first.object_id # => 4087
�p r.first �# segfault
�break
end

And we see that there's an extraneous variable reported by evaluating
local_variables. The first element of the result seems an invalid
pointer?

for i in 1..100
�p Kernel.eval("local_variables") # this works
�break
end



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