The compiler actually doesn't need any functional changes for this: Sema
does reification based on the tag indices of `std.builtin.Type` already!
So, no zig1.wasm update is necessary.
This change is necessary to disallow name clashes between fields and
decls on a type, which is a prerequisite of #9938.
Use inline to vastly simplify the exposed API. This allows a
comptime-known endian parameter to be propogated, making extra functions
for a specific endianness completely unnecessary.
The idea here is to avoid code bloat by having only one actual io.Reader
implementation, which is type erased, and then implement a GenericReader
that preserves type information on top of that as thin glue code.
The strategy here is for that glue code to `@errSetCast` the result of
the type-erased reader functions, however, while trying to do that I
ran into #17343.
