diff -ru ProofGeneral-4.2.orig/Makefile ProofGeneral-4.2/Makefile
--- ProofGeneral-4.2.orig/Makefile	2012-03-05 19:52:34.000000000 +0100
+++ ProofGeneral-4.2/Makefile	2014-08-04 15:47:47.153429700 +0200
@@ -19,6 +19,8 @@
 ## 
 ###########################################################################
 
+UNAME_S=$(shell uname -s)
+
 # Set this according to your version of Emacs.
 # NB: this is also used to set default install path names below.
 EMACS=$(shell if [ -z "`which emacs`" ]; then echo "Emacs executable not found"; exit 1; else echo emacs; fi)
@@ -35,9 +37,13 @@
 PREFIX=$(DESTDIR)/usr
 DEST_PREFIX=$(DESTDIR)/usr
 
-PWD=$(shell pwd)
+PWD:=$(shell pwd)
+
+ifneq (,$(findstring CYGWIN,$(UNAME_S)))
+  PWD:=$(shell cygpath -m "$(PWD)")
+endif
 
-PROVERS=acl2 ccc coq hol98 isar lego hol-light phox pgshell pgocaml pghaskell
+PROVERS=acl2 ccc coq easycrypt hol98 isar lego hol-light phox pgshell pgocaml pghaskell
 OTHER_ELISP=generic lib contrib/mmm
 ELISP_DIRS=${PROVERS} ${OTHER_ELISP}
 ELISP_EXTRAS=isar/interface isar/isartags
@@ -62,7 +68,7 @@
 # only during compilation.  Another idea: put a function in proof-site
 # to output the compile-time load path and ELISP_DIRS so these are set
 # just in that one place.
-BYTECOMP = $(BATCHEMACS) -eval '(setq load-path (append (mapcar (lambda (d) (concat "${PWD}/" (symbol-name d))) (quote (${ELISP_DIRS}))) load-path))' -eval '(progn (require (quote bytecomp)) (require (quote mouse)) (require (quote tool-bar)) (require (quote fontset)) (setq byte-compile-warnings (remove (quote cl-functions) (remove (quote noruntime) byte-compile-warning-types))) (setq byte-compile-error-on-warn t))' -f batch-byte-compile
+BYTECOMP := $(BATCHEMACS) -eval '(setq load-path (append (mapcar (lambda (d) (concat "$(PWD)/" (symbol-name d))) (quote (${ELISP_DIRS}))) load-path))' -eval '(progn (require (quote bytecomp)) (require (quote mouse)) (require (quote tool-bar)) (require (quote fontset)) (setq byte-compile-warnings (remove (quote cl-functions) (remove (quote noruntime) byte-compile-warning-types))))' -f batch-byte-compile
 EL=$(shell for f in $(ELISP_DIRS); do ls $$f/*.el; done)
 ELC=$(EL:.el=.elc)