When going through the RubySpecs for 1.9, I found that the following code
will hang the 1.9 VM:

hsh = {1 => 2, 3 => 4, 5 => 6}
hsh.merge!(hsh) {|x, y, z| p [x, y, z]; hsh.shift; true }
p hsh

The output in 1.8:
[5, 6, 6]
[1, 2, 2]
[3, 4, 4]
{3=>true}


-- 
Yehuda Katz
Developer | Engine Yard
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