Radix cross Linux 3pp sources

diff --git a/packages/l/isl/Makefile b/packages/l/isl/Makefile
new file mode 100644
index 0000000..0c650ec
--- /dev/null
+++ b/packages/l/isl/Makefile
@@ -0,0 +1,38 @@
+#
+# Project Home:
+# ============
+# http://freecode.com/projects/isl
+# http://isl.gforge.inria.fr/
+#
+# Downloads:
+# =========
+# http://isl.gforge.inria.fr/
+# https://libisl.sourceforge.io/
+#
+
+url         = https://libisl.sourceforge.io
+
+versions    = 0.15 0.16 0.16.1 0.17 0.17.1 0.18 0.19 0.20 0.22 0.22.1 0.23 0.24 0.25
+
+tarballs    = $(addsuffix .tar.xz, $(addprefix isl-, $(versions)))
+sha1s       = $(addsuffix .sha1sum, $(tarballs))
+
+
+all: $(tarballs) $(sha1s)
+
+.PHONY: downloads_clean
+
+$(tarballs):
+	@echo -e "\n======= Downloading source tarballs =======\n"
+	@for tarball in $(tarballs) ; do \
+	  wget -N $(url)/$$tarball ; \
+	done
+
+$(sha1s): %.tar.xz.sha1sum : %.tar.xz
+	@for tarball in $< ; do \
+	  echo -e "\n======= Calculation the '$$tarball' sha1sum =======\n" ; \
+	  sha1sum --binary $$tarball > $$tarball.sha1sum ; \
+	done
+
+downloads_clean:
+	@rm -rf $(tarballs) $(sha1s)