diff --git a/ChangeLog b/ChangeLog
index cc2c7770e..071ef02ac 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2018-04-01  Werner Lemberg  <wl@gnu.org>
+
+	* builds/toplevel.mk (work): Use $(SEP).
+
+	This fixes the `make refdoc' using Cygwin: $(CAT) is `type' on this
+	platform, and this program only understands backslashes in paths.
+
+	Reported by Nikhil Ramakrishnan <ramakrishnan.nikhil@gmail.com>.
+
 2018-03-30  Werner Lemberg  <wl@gnu.org>
 
 	[truetype] Fix memory leak (only if tracing is on).
diff --git a/builds/toplevel.mk b/builds/toplevel.mk
index f51ad16b9..7ce0ed8db 100644
--- a/builds/toplevel.mk
+++ b/builds/toplevel.mk
@@ -172,7 +172,8 @@ include $(TOP_DIR)/builds/modules.mk
 # get FreeType version string, using a
 # poor man's `sed' emulation with make's built-in string functions
 #
-work := $(strip $(shell $(CAT) $(TOP_DIR)/include/freetype/freetype.h))
+work := $(strip $(shell $(CAT) \
+                  $(subst /,$(SEP),$(TOP_DIR)/include/freetype/freetype.h)))
 work := $(subst |,x,$(work))
 work := $(subst $(space),|,$(work))
 work := $(subst \#define|FREETYPE_MAJOR|,$(space),$(work))