The modified patch for go1.10beta1 of WSL (Windows Subsystem Linux) specific problem of os.RemoveAll(): https://github.com/vim-volt/volt/issues/1

path.diff

--- src/os/path.go.old	2017-12-11 19:45:29.722217500 +0900
+++ src/os/path.go	2017-12-11 19:51:19.668455900 +0900
@@ -84,26 +84,35 @@
 		return err
 	}
 
-	// Directory.
-	fd, err := Open(path)
-	if err != nil {
-		if IsNotExist(err) {
-			// Race. It was deleted between the Lstat and Open.
-			// Return nil per RemoveAll's docs.
-			return nil
+	// nextNames enumerates the entries of path, which is a directory.
+	// In POSIX the behavior of Readdir after asynchronous removal of files is
+	// undefined. To remove all files, on all filesystems across all platforms, one
+	// must re-open the directory fd between enumerations.
+	nextNames := func(prevErr error) ([]string, error) {
+		fd, err := Open(path)
+		if err != nil {
+			if IsNotExist(err) {
+				// Race. It was deleted between the Lstat and Open.
+				// Return nil per RemoveAll's docs.
+				return nil, nil
+			}
+			return nil, err
 		}
-		return err
-	}
+		defer fd.Close()
 
-	// Remove contents & return first error.
-	err = nil
-	for {
-		if err == nil && (runtime.GOOS == "plan9" || runtime.GOOS == "nacl") {
+		if prevErr == nil && (runtime.GOOS == "plan9" || runtime.GOOS == "nacl") {
 			// Reset read offset after removing directory entries.
 			// See golang.org/issue/22572.
 			fd.Seek(0, 0)
 		}
-		names, err1 := fd.Readdirnames(100)
+
+		return fd.Readdirnames(1024)
+	}
+
+	// Remove contents & return first error.
+	err = nil
+	for {
+		names, err1 := nextNames(err)
 		for _, name := range names {
 			err1 := RemoveAll(path + string(PathSeparator) + name)
 			if err == nil {
@@ -122,9 +131,6 @@
 		}
 	}
 
-	// Close directory, because windows won't remove opened directory.
-	fd.Close()
-
 	// Remove directory.
 	err1 := Remove(path)
 	if err1 == nil || IsNotExist(err1) {