Yarn fails to run under Cygwin

[jeghers]

Installed latest stable Yarn using the Windows installer.

In Cygwin, I get this:

$ yarn -v
cygpath: can't convert empty path
module.js:471
    throw err;
    ^

Error: Cannot find module 'E:\yarn.js'
    at Function.Module._resolveFilename (module.js:469:15)
    at Function.Module._load (module.js:417:25)
    at Module.runMain (module.js:604:10)
    at run (bootstrap_node.js:389:7)
    at startup (bootstrap_node.js:149:9)
    at bootstrap_node.js:504:3

Also get the same behavior if yarn was installed under npm, either globally or local to a single project.