Major Description
When native Linux libraries are present, and bin/hadoop is running under Cygwin, the part of the script that sets up java.library.path uses un-translated CLASSPATH. This leads to the (in)famous message:
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/hadoop/util/PlatformName
The fix is to perform the Cygwin translation of the CLASSPATH earlier, before checking for the native libs.