Issue #20614 has been updated by Hanmac (Hans Mackowiak). @eragon might be because of FLONUM using the other half? But the restriction of only half of 64-bit is way older than FLONUM implementation ---------------------------------------- Bug #20614: Integer#size returns incorrect values on 64-bit Windows https://bugs.ruby-lang.org/issues/20614#change-109189 * Author: surusek (Łukasz Sur) * Status: Rejected * ruby -v: ruby 3.4.0dev (2024-07-08T11:00:01Z master 02c4f0c89d [x64-mswin64_140] * Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN ---------------------------------------- According to the ruby/spec, `0.size` should return size of the machine word in bytes, but on x64-mswin64_140 (both release 3.3.3 and git revision 02c4f0c89d) it doesn't. Following example: ``` ruby a, b = 0.size, [0].pack('J').length puts a, b ``` should print two `8`s, but on x64-mswin64_140, a is `4`. Issue is most likely caused by use of `long` instead of `SIGNED_VALUE` in internal/fixnum.h and `fix_size` function in numeric.c, because on Windows, `long` is always a 32-bit number. -- https://bugs.ruby-lang.org/