It seems that pyenv cannot install 2.7.18 on Mac M1 (Apple ARM).
openssl 1.0.2 does not have ARM support. M1 support was added in 1.1.1i according to
https://www.openssl.org/news/cl111.txt
Ensuring that all dirs in LDFLAGS exist is only needed for Ruby due to its `configure` requirements.
If some LDFLAGS entries point to a nonexisting path to which the user doesn't have permission. this causes a build failure.