I use this change to make preprocessor.pm / make_names.pl work under msys/mingw. Maybe it is related to bug #143765, thus feel free to pick one of them. I use this (simpler) version. Please note of the second chunk in preprocessor.pm too.
Created attachment 251074 [details] proposed wk patch
Committed to 2.4 http://trac.webkit.org/changeset/184470