pub const TARGETS: &[TargetEntry];Expand description
Every target the compiler has an opinion about.
Adding a row here is the entry price for spec/cross-compile/02-the-goal.md claim 3: bringing up a target
should be a data change, and this is the data. A row that needs code outside the target crate
is a row that has found a leak in the abstraction, and the leak is the bug rather than the
row.