* `-A<arch>` | `--arch=<arch>` | `--target=<arch>`
Specify target architecture. If `<arch>` starts with a capital
- ascii letter, is an alias for some other arch: it is looked up
+ ascii letter, it is an alias for some other arch: it is looked up
in the configuration, and then in the builtin arch alias list.
The builtin list is equivalent to: `[arch]`
`RPI='arm-unknown-linux-gnueabihf'`.