I am adding the reverting commit on this PR https://github.com/ruby/ruby/pull/8739. The make install in Travis arm64, ppc64le and s390x failed by the following error. And the reverting commit fixed the issue.
$ make -s install
Cloning https://github.com/ruby/rbs
Update rbs to 2cac4e78dfd76e85342ab2c332d3fae046b36961
../.bundle/.timestamp/rbs.revision updated
Building rbs@2cac4e78dfd76e85342ab2c332d3fae046b36961 to ../gems/rbs-3.2.2.gem
The command "make -s install" failed and exited with 2 during .