Hi Folks,
I just found a bug in an edge case in #truncated primitive in 64 bits Cog Spur (tested on Linux, both in Cuis and Squeak). It is when #truncated a Float that is slightly larger than SmallInteger maxVal.
SmallInteger maxVal --> 1152921504606846975
If we take (1152921504606846975.0 predecessor), to ensure a Float that still fits in a SmallInteger, everything works fine:
1152921504606846975.0 predecessor asTrueFraction --> 1152921504606846848 1152921504606846975.0 predecessor asTrueFraction --> class SmallInteger 1152921504606846975.0 predecessor truncated --> 1152921504606846848
But taking 1152921504606846976.0:
1152921504606846976.0 asTrueFraction --> 1152921504606846976 (correct result) 1152921504606846976.0 asTrueFraction class --> LargePositiveInteger (ok. Doesn't fit in SmallInteger) 1152921504606846976.0 truncated --> -1152921504606846976
The primitive is answering SmallInteger minVal, (a negative number!) but it should fail, as the correct result doesn't fit in a SmallInteger.
Thanks,
Hi Juan, good find. Can you open an issue on github opensmalltalk repo?
Le mar. 12 mars 2019 à 16:05, Juan Vuletich JuanVuletich@zoho.com a écrit :
Hi Folks,
I just found a bug in an edge case in #truncated primitive in 64 bits Cog Spur (tested on Linux, both in Cuis and Squeak). It is when #truncated a Float that is slightly larger than SmallInteger maxVal.
SmallInteger maxVal --> 1152921504606846975
If we take (1152921504606846975.0 predecessor), to ensure a Float that still fits in a SmallInteger, everything works fine:
1152921504606846975.0 predecessor asTrueFraction --> 1152921504606846848 1152921504606846975.0 predecessor asTrueFraction --> class SmallInteger 1152921504606846975.0 predecessor truncated --> 1152921504606846848
But taking 1152921504606846976.0:
1152921504606846976.0 asTrueFraction --> 1152921504606846976 (correct result) 1152921504606846976.0 asTrueFraction class --> LargePositiveInteger (ok. Doesn't fit in SmallInteger) 1152921504606846976.0 truncated --> -1152921504606846976
The primitive is answering SmallInteger minVal, (a negative number!) but it should fail, as the correct result doesn't fit in a SmallInteger.
Thanks,
-- Juan Vuletich www.cuis-smalltalk.org https://github.com/Cuis-Smalltalk/Cuis-Smalltalk-Dev https://github.com/jvuletich https://www.linkedin.com/in/juan-vuletich-75611b3 @JuanVuletich
Hi Nicolas,
Done. It is https://github.com/OpenSmalltalk/opensmalltalk-vm/issues/376
Thanks,
vm-dev@lists.squeakfoundation.org