--- Makefile.am.orig	2016-07-03 05:46:33.000000000 +0300
+++ Makefile.am.new	2016-07-08 16:43:10.325483712 +0300
@@ -6,3 +6,89 @@
 	gtkrc.mac-dark \
 	gtkrc.win32 \
 	gtkrc.win32-dark
+
+srcdirstrip := $(shell echo "$(srcdir)" | sed 's/[].[^$$\\*]/\\\\&/g')
+topsrcdirstrip := $(shell echo "$(top_srcdir)" | sed 's/[].[^$$\\*]/\\\\&/g')
+
+define EOL
+$(eval)
+$(eval)
+endef
+
+define DISTDIR_PROCESS_IN_GROUPS
+$(eval _args:=)
+$(foreach obj,$1,$(eval _args+=$(obj))$(if $(word $2,$(_args)),$(call $3,$(_args))$(EOL)$(eval _args:=)))
+$(if $(_args),$(call $3,$(_args)))
+endef
+
+define DISTDIR_REPLACEMENTS_CMD
+	for file in $1; do echo $$file; done | \
+	   sed -e "s|^${srcdirstrip}/||;t" \
+	       -e "s|^${topsrcdirstrip}/|${top_builddir}/|;t";
+endef
+
+define DISTDIR_REPLACEMENTS
+$(shell $(DISTDIR_REPLACEMENTS_CMD))
+endef
+
+$(eval EDITED_DISTFILES:=$(sort $(subst ${EOL}, ,$(call DISTDIR_PROCESS_IN_GROUPS,${DISTFILES},10,DISTDIR_REPLACEMENTS))))
+
+########################################################################################################
+# compute list of directories
+
+define DISTDIR_PROCESSDIRS_CMD
+	for file in $1; do case "$$file" in \
+	  */*) echo $$file | sed '/\//!d;s|^|$(distdir)/|;s,/[^/]*$$,,' ;; \
+	esac; \
+	done
+endef
+
+define DISTDIR_PROCESSDIRS
+$(shell ${DISTDIR_PROCESSDIRS_CMD})
+endef
+
+$(eval DISTDIR_DIRECTORY_LIST:=$(sort $(subst ${EOL}, ,$(call DISTDIR_PROCESS_IN_GROUPS,${EDITED_DISTFILES},10,DISTDIR_PROCESSDIRS))))
+
+########################################################################################################
+# create directories
+
+define DISTDIR_MKDIR_CMD
+	$(MKDIR_P) $1
+endef
+
+define DISTDIR_MKDIR
+$(eval $(shell ${DISTDIR_MKDIR_CMD}))
+endef
+
+########################################################################################################
+# copy files
+
+define DISTDIR_COPYING_CMD
+	for file in $1; do \
+	  if test -f $$file || test -d $$file; then d=.; else d=$(srcdir); fi; \
+	  if test -d $$d/$$file; then \
+	    dir=`echo "/$$file" | sed -e 's,/[^/]*$$,,'`; \
+	    if test -d "$(distdir)/$$file"; then \
+	      find "$(distdir)/$$file" -type d ! -perm -700 -exec chmod u+rwx {} \;; \
+	    fi; \
+	    if test -d $(srcdir)/$$file && test $$d != $(srcdir); then \
+	      cp -fpR $(srcdir)/$$file "$(distdir)$$dir" || exit 1; \
+	      find "$(distdir)/$$file" -type d ! -perm -700 -exec chmod u+rwx {} \;; \
+	    fi; \
+	    cp -fpR $$d/$$file "$(distdir)$$dir" || exit 1; \
+	  else \
+	    test -f "$(distdir)/$$file" \
+	    || cp -p $$d/$$file "$(distdir)/$$file" \
+	    || exit 1; \
+	  fi; \
+	done
+endef
+
+define DISTDIR_COPYING
+$(eval $(shell ${DISTDIR_COPYING_CMD}))
+endef
+
+distdir: $(DISTFILES)
+	$(call DISTDIR_PROCESS_IN_GROUPS,${DISTDIR_DIRECTORY_LIST},10,DISTDIR_MKDIR)
+	$(call DISTDIR_PROCESS_IN_GROUPS,${EDITED_DISTFILES},10,DISTDIR_COPYING)
+	@# this silent empty line mutes "nothing to be done" warning