Incorrect Result in 32 Bit Platforms about bigdecimal HOT 4 CLOSED

Thank you for your report. I'll check and fix it asap.

from bigdecimal.

@nmingotti
This is a limitation of the current implementation of bigdecimal.
The reason why the result of the latter case is Infinity is that bigdecimal just returns Infinity for a positive integral exponent whose internal type is T_BIGNUM.
In 32-bit platforms, sizeof(long) is 4, so BigDecimal#** just returns Infinity because 1_000_000_000_0 is internally a bignum.

I want to and have a plan to remove this limitation, but it isn't scheduled yet.

The corresponding code location is here:
https://github.com/ruby/bigdecimal/blob/master/ext/bigdecimal/bigdecimal.c#L2507-L2516

from bigdecimal.

@mrkn ok, thank for checking out !
In the meanwhile, If it is possible and not to tedious to implement, could you rise an exception when the exponent goes out of the supported range ?
This would be useful, getting Infinity as final result is confusing.

from bigdecimal.

@nmingotti Setting the exception mode, you can get FloatDomainError in that cases:

[2] pry(main)> BigDecimal.mode(BigDecimal::EXCEPTION_INFINITY, true)
=> 1
[3] pry(main)> n = 1_000_000_000_0
=> 10000000000
[4] pry(main)> BigDecimal(2) ** n
FloatDomainError: Computation results to 'Infinity'
from (pry):4:in `**'
[5] pry(main)>

from bigdecimal.