[PyPy-issue] [issue636] 64bit JIT Failure on trunk

[Bob Ziuchkovski]

Bob Ziuchkovski <bob.ziuchkovski at gmail.com> added the comment:

I have done a final bit of testing and it seems this error is specifically tied 
to unrolling a loop that contains a floating point variable as input.  
Furthermore, it appears the floating point value of the variable is lost and 
something very close to the 64bit minimum positive double value is used instead.  
The result of the attached floating_point_unroll_error.py is that after 
unrolling with the following arithmetic results occur:

# below, floatvar stores 2.0
1 * floatvar returns 6.92386558364043e-310
1 + floatvar returns 1.0
1 - floatvar returns 1.0

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