swift234

Allow -o to refer to an output directory.

In this case, the output filename is taken from the module name.

  swift -emit-module x/y.swift
    -> x/y.swiftmodule
  swift -emit-module x/y.swift -module-name z
    -> x/z.swiftmodule
  swift -emit-module x/y.swift -o w/
    -> w/y.swiftmodule
  swift -emit-module x/y.swift -o w/ -module-name z
    -> w/z.swiftmodule
  swift -emit-module x/y.swift -o explicit.module
    -> ./explicit.module

Swift SVN r6854