diff -ru orig/winsup/mingw/Makefile.in src/winsup/mingw/Makefile.in
--- orig/winsup/mingw/Makefile.in	2009-07-27 16:27:09.000000000 -0400
+++ src/winsup/mingw/Makefile.in	2009-08-18 21:56:33.968750000 -0400
@@ -86,10 +86,11 @@
 # configure script should simply assign appropriate values to
 # the standard macros, which should be used herein.
 #
-inst_bindir:=$(tooldir)/bin
-inst_includedir:=$(tooldir)/include/mingw
-inst_libdir:=$(tooldir)/lib/mingw
-inst_docdir:=$(tooldir)/share/doc/mingw-runtime
+inst_bindir:=$(DESTDIR)$(tooldir)/bin
+inst_includedir:=$(DESTDIR)$(tooldir)/include/mingw
+inst_libdir:=$(DESTDIR)$(tooldir)/lib/mingw
+inst_docdir:=$(DESTDIR)$(tooldir)/share/doc/mingw-runtime
+inst_mandir:=$(DESTDIR)$(mandir)
 else
 ifneq (,$(with_cross_host))
 #
@@ -100,15 +101,17 @@
 # of these settings is the prerogative of the configure script,
 # and they should use standard names, as noted above.
 #
-inst_bindir:=$(tooldir)/bin
-inst_includedir:=$(tooldir)/include
-inst_libdir:=$(tooldir)/lib
-inst_docdir:=$(tooldir)/share/doc/mingw-runtime
+inst_bindir:=$(DESTDIR)$(tooldir)/bin
+inst_includedir:=$(DESTDIR)$(tooldir)/include
+inst_libdir:=$(DESTDIR)$(tooldir)/lib
+inst_docdir:=$(DESTDIR)$(tooldir)/share/doc/mingw-runtime
+inst_mandir:=$(DESTDIR)$(mandir)
 else
-inst_bindir:=$(bindir)
-inst_includedir:=$(includedir)
-inst_libdir:=$(libdir)
-inst_docdir:=$(prefix)/doc/runtime
+inst_bindir:=$(DESTDIR)$(bindir)
+inst_includedir:=$(DESTDIR)$(includedir)
+inst_libdir:=$(DESTDIR)$(libdir)
+inst_docdir:=$(DESTDIR)$(prefix)/doc/runtime
+inst_mandir:=$(DESTDIR)$(mandir)
 endif
 endif
 
@@ -195,6 +198,7 @@
 # FIXME: Most of these are either redundant, or should be set
 # directly in the subdirectories' Makefiles, by `configure'.
 FLAGS_TO_PASS:=\
+	DESTDIR="$(DESTDIR)" \
 	AS="$(AS)" \
 	CC="$(CC)" \
 	CFLAGS="$(CFLAGS) $(CFLAGS_COMMON) $(CFLAGS_CONFIG)" \
@@ -498,7 +502,7 @@
 	$(mkinstalldirs) $(inst_includedir)
 	$(mkinstalldirs) $(inst_libdir)
 	$(mkinstalldirs) $(inst_docdir)
-	$(mkinstalldirs) $(mandir)/man$(mansection)
+	$(mkinstalldirs) $(inst_mandir)/man$(mansection)
 
 install: all install-dirs $(install_dlls_host)
 	for i in $(LIBS); do \
@@ -521,10 +525,10 @@
 # This provisional hack installs the only manpage we have at present...
 # It simply CANNOT suffice, when we have more manpages to ship.
 #
-	$(mkinstalldirs) $(mandir)/man$(mansection)
-	$(INSTALL_DATA) $(srcdir)/man/dirname.man $(mandir)/man$(mansection)/`\
+	$(mkinstalldirs) $(inst_mandir)/man$(mansection)
+	$(INSTALL_DATA) $(srcdir)/man/dirname.man $(inst_mandir)/man$(mansection)/`\
 	  echo dirname.man|sed '$(manpage_transform);s,man$$,$(mansection),'`
-	$(INSTALL_DATA) $(srcdir)/man/dirname.man $(mandir)/man$(mansection)/`\
+	$(INSTALL_DATA) $(srcdir)/man/dirname.man $(inst_mandir)/man$(mansection)/`\
 	  echo basename.man|sed '$(manpage_transform);s,man$$,$(mansection),'`
 #
 # End provisional hack.
diff -ru orig/winsup/w32api/lib/Makefile.in src/winsup/w32api/lib/Makefile.in
--- orig/winsup/w32api/lib/Makefile.in	2008-01-29 16:18:49.000000000 -0500
+++ src/winsup/w32api/lib/Makefile.in	2009-08-18 21:24:16.281250000 -0400
@@ -41,15 +41,15 @@
 datadir = @datadir@
 infodir = @infodir@
 ifneq (,$(findstring cygwin,$(target_alias)))
-inst_includedir:=$(tooldir)/include/w32api
-inst_libdir:=$(tooldir)/lib/w32api
+inst_includedir:=$(DESTDIR)$(tooldir)/include/w32api
+inst_libdir:=$(DESTDIR)$(tooldir)/lib/w32api
 else
 ifneq (,$(with_cross_host))
-inst_includedir:=$(tooldir)/include/w32api
-inst_libdir:=$(tooldir)/lib
+inst_includedir:=$(DESTDIR)$(tooldir)/include/w32api
+inst_libdir:=$(DESTDIR)$(tooldir)/lib
 else
-inst_includedir:=$(includedir)
-inst_libdir:=$(libdir)
+inst_includedir:=$(DESTDIR)$(includedir)
+inst_libdir:=$(DESTDIR)$(libdir)
 endif
 endif
 
diff -ru orig/winsup/w32api/lib/ddk/Makefile.in src/winsup/w32api/lib/ddk/Makefile.in
--- orig/winsup/w32api/lib/ddk/Makefile.in	2006-09-11 20:29:04.000000000 -0400
+++ src/winsup/w32api/lib/ddk/Makefile.in	2009-08-18 21:32:45.468750000 -0400
@@ -37,15 +37,15 @@
 datadir = @datadir@
 infodir = @infodir@
 ifneq (,$(findstring cygwin,$(target_alias)))
-inst_includedir:=$(tooldir)/include/w32api/ddk
-inst_libdir:=$(tooldir)/lib/w32api
+inst_includedir:=$(DESTDIR)$(tooldir)/include/w32api/ddk
+inst_libdir:=$(DESTDIR)$(tooldir)/lib/w32api
 else
 ifneq (,$(with_cross_host))
-inst_includedir:=$(tooldir)/include/w32api/ddk
-inst_libdir:=$(tooldir)/lib
+inst_includedir:=$(DESTDIR)$(tooldir)/include/w32api/ddk
+inst_libdir:=$(DESTDIR)$(tooldir)/lib
 else
-inst_includedir:=$(includedir)/ddk
-inst_libdir:=$(libdir)
+inst_includedir:=$(DESTDIR)$(includedir)/ddk
+inst_libdir:=$(DESTDIR)$(libdir)
 endif
 endif
 
diff -ru orig/winsup/w32api/lib/directx/Makefile.in src/winsup/w32api/lib/directx/Makefile.in
--- orig/winsup/w32api/lib/directx/Makefile.in	2006-09-11 20:29:04.000000000 -0400
+++ src/winsup/w32api/lib/directx/Makefile.in	2009-08-18 21:39:49.750000000 -0400
@@ -37,15 +37,15 @@
 datadir = @datadir@
 infodir = @infodir@
 ifneq (,$(findstring cygwin,$(target_alias)))
-inst_includedir:=$(tooldir)/include/w32api
-inst_libdir:=$(tooldir)/lib/w32api
+inst_includedir:=$(DESTDIR)$(tooldir)/include/w32api
+inst_libdir:=$(DESTDIR)$(tooldir)/lib/w32api
 else
 ifneq (,$(with_cross_host))
-inst_includedir:=$(tooldir)/include/w32api
-inst_libdir:=$(tooldir)/lib
+inst_includedir:=$(DESTDIR)$(tooldir)/include/w32api
+inst_libdir:=$(DESTDIR)$(tooldir)/lib
 else
-inst_includedir:=$(includedir)
-inst_libdir:=$(libdir)
+inst_includedir:=$(DESTDIR)$(includedir)
+inst_libdir:=$(DESTDIR)$(libdir)
 endif
 endif