used to build the custom libstd that Miri uses, and Miri failed to detect that.
Try deleting `~/.cache/miri`.
+#### "no mir for `std::rt::lang_start_internal`"
+
+This means the sysroot you are using was not compiled with Miri in mind. This
+should never happen when you use `cargo miri` because that takes care of setting
+up the sysroot. If you are using `miri` (the Miri driver) directly, see
+[below][testing-miri] for how to set up the sysroot.
+
## Development and Debugging
If you want to hack on miri yourself, great! Here are some resources you might