Generated module-info.java files now contain comments of the form:

module java.base {^M
    // source file: d:\java\ws\uvwxyz\jdk\src\java.base\share\classes\module-i
nfo.java^M
    // d:\java\ws\uvwxyz\jdk\src\java.base\windows\classes\module
-info.java.extra^M
    // d:\java\ws\uvwxyz\jdk\src\closed\java.base\share\classes\m
odule-info.java.extra^M

and javac treats \uvwxyz as invalid Unicode.

d:\java\ws\uvwxyz\build\windows-x86_64-normal-server-fastdebug\support\gensrc\java.base\module-info.java:30: error: illegal unicode escape

Possibly output these paths using "/" instead (cygwin-style)?

Workaround is to not use directories that start with u.