when $MJIT_SEARCH_BUILD_DIR is set.
If prefix path is owned by root, `make install` needs to be run by root.
But in general we don't want to run `make test-all`, and also running
`make test-all` currently fails due to permission tests of rdoc and rubygems.
Thus, prior to this commit, specifying a prefix like "/usr/local" could
mean there was no way to pass test-all.
So we should not depend on `make install` for `make test-all`. Thus I
reverted r64104 and r64103, and applied this workaround to pass `make
test-all` without `make install`.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64143 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
11974fc010