* GC
* incompatible changes:
* Rename GC.stat entries. [Feature #9924]
* IO
* incompatible changes:
* When flushing file IO with IO#flush, you cannot assume that the metadata
of the file is updated immediately. On some platforms (especially
Windows), it is delayed until the filesystem load is decreased.
Use IO#fsync if you want to guarantee updating metadata.* Math
* incompatible changes:
* Math.log now raises Math::DomainError instead of returning NaN if the
base is less than 0, and returns NaN instead of -infinity if both of
two arguments are 0.
* Math.atan2 now returns values like as expected by C99 if both two
arguments are infinity.
* Proc
* incompatible changes:
* ArgumentError is no longer raised when lambda Proc is passed as a
block, and the number of yielded arguments does not match the formal
arguments of the lambda, if just an array is yielded and its length
matches.
* Process
* Process execution methods such as Process.spawn opens the file in write
mode for redirect from [:out, :err].
Before Ruby 2.2, it was opened in read mode.
для минорной версии маловато поломок.