py38-cryptography @3.4.7+universal: error[E0463]: can't find crate for `core`

[ryandesign (Ryan Carsten Schmidt)]

py38-cryptography fails to build with the universal variant on High Sierra:

:info:build error[E0463]: can't find crate for `core`
:info:build   |
:info:build   = note: the `i686-apple-darwin` target may not be installed
:info:build error[E0463]: can't find crate for `core`
:info:build   |
:info:build   = note: the `i686-apple-darwin` target may not be installed
:info:build error[E0463]: can't find crate for `core`
:info:build   |
:info:build   = note: the `i686-apple-darwin` target may not be installed
:info:build error: aborting due to previous error
:info:build error: aborting due to previous error
:info:build For more information about this error, try `rustc --explain E0463`.
:info:build For more information about this error, try `rustc --explain E0463`.
:info:build error: aborting due to previous error
:info:build For more information about this error, try `rustc --explain E0463`.
:info:build error: could not compile `smallvec`
:info:build Caused by:
:info:build   process didn't exit successfully: `rustc --crate-name smallvec --edition=2018 /opt/local/var/macports/build/_Users_rschmidt_macports_macports-ports-ryandesign-fork_python_py-cryptography/py38-cryptography/work/.home/.cargo/macports/smallvec-1.6.1/src/lib.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts --crate-type lib --emit=dep-info,metadata,link -C opt-level=3 -C linker-plugin-lto -C metadata=f34bfd05c5902fe9 -C extra-filename=-f34bfd05c5902fe9 --out-dir /opt/local/var/macports/build/_Users_rschmidt_macports_macports-ports-ryandesign-fork_python_py-cryptography/py38-cryptography/work/cryptography-3.4.7-i386/src/rust/target/i686-apple-darwin/release/deps --target i686-apple-darwin -L dependency=/opt/local/var/macports/build/_Users_rschmidt_macports_macports-ports-ryandesign-fork_python_py-cryptography/py38-cryptography/work/cryptography-3.4.7-i386/src/rust/target/i686-apple-darwin/release/deps -L dependency=/opt/local/var/macports/build/_Users_rschmidt_macports_macports-ports-ryandesign-fork_python_py-cryptography/py38-cryptography/work/cryptography-3.4.7-i386/src/rust/target/release/deps --cap-lints allow -C linker=/usr/bin/clang -C 'link-args=-Wl,-install_name,@rpath/_rust.abi3.so'` (exit code: 1)
:info:build warning: build failed, waiting for other jobs to finish...
:info:build error: build failed
:info:build cargo rustc --lib --manifest-path src/rust/Cargo.toml --features pyo3/abi3-py36 pyo3/extension-module --target i686-apple-darwin --release --verbose -- --crate-type cdylib -C link-arg=-undefined -C link-arg=dynamic_lookup
:info:build     =============================DEBUG ASSISTANCE=============================
:info:build     If you are seeing a compilation error please try the following steps to
:info:build     successfully install cryptography:
:info:build     1) Upgrade to the latest pip and try again. This will fix errors for most
:info:build        users. See: https://pip.pypa.io/en/stable/installing/#upgrading-pip
:info:build     2) Read https://cryptography.io/en/latest/installation.html for specific
:info:build        instructions for your platform.
:info:build     3) Check our frequently asked questions for more information:
:info:build        https://cryptography.io/en/latest/faq.html
:info:build     4) Ensure you have a recent Rust toolchain installed:
:info:build        https://cryptography.io/en/latest/installation.html#rust
:info:build     5) If you are experiencing issues with Rust for *this release only* you may
:info:build        set the environment variable `CRYPTOGRAPHY_DONT_BUILD_RUST=1`.
:info:build     =============================DEBUG ASSISTANCE=============================
:info:build     
:info:build error: cargo failed with code: 101

I guess since it uses rust now it has to set supported_archs arm64 x86_64 like rust does.

[mascguy (Christopher Nielsen)]

Of note, all py-cryptography ports are now failing to build for MacOS 10.12 and earlier. It appears to be a different issue than what's seen here though.

See issue:62843

[cjones051073 (Chris Jones)]

Yes, I am looking into an issue with the universal variant activated with the wrappers.....