According to the documentation .. Debugging keystore is in the path: $ HOME / .android / debug.keystore and if it is not there, it will automatically generate it (after checking your application in debug mode)
read this from the Android developer documentation .
Eclipse JDK - Windows Cygwin :
keytool -genkeypair -alias androiddebugkey -keypass android -keystore debug.keystore -storepass android -dname "CN=Android Debug,O=Android,C=US" -validity 9999
Keytool JDK PATH . : C:\\bin
. Cygwin ( cygwin), debug.keystore: C:\\home\\