Motivation: [autocfg panics when building with `-Zbuild-std`][1].
Instead of panicking when the `i128` feature is requested but
`probe_type("i128")` fails, just go ahead and enable the feature. If
`i128` truly isn't available then compilation will still fail, just
later on. This is unlikely to be an issue in practice since [`i128`
was stabilized in Rust 1.26.0][2].
Tested by building with:
cargo +nightly build --target=x86_64-unknown-uefi \
-Zbuild-std=core,alloc --no-default-features \
--features=i128
[1]: https://github.com/cuviper/autocfg/issues/34
[2]: https://github.com/rust-lang/rust/blob/master/RELEASES.md#version-1260-2018-05-10
* no_std support
* Use integer log2 when possible to estimate allocations
* Remove std features from a few dependencies
* Use libm for missing funcs in nostd environment
* Use autocfg to detect presence of i128
* Better CI test for nostd environment
* Move benchmark to a separate crate
* Make the tests pass in no_std builds
* Use thumbv7m target for nostd build test
* Add documentation about the no-std compatibility
* Make zeroize and prime features no_std-compatible
* Test each feature in nostd context
* Fix mac test to work in no_std environment
* Avoid using thread_rng in nostd tests
* Fix prime tests in nostd mode
* Fix all warnings and errors
* Only test nostd builds on nightly on travis
* Travis: Only do nostd builds on nightly
