Merge pull request libmapper#115 from EggAllocationService/issue-114

make configure.ac work if there's no tags

Author: malloch

configure.ac

@@ -2,7 +2,7 @@ AC_PREREQ(2.61)
 
 m4_define([LIBMAPPER_VERSION],[2.5.2])
 AC_INIT([libmapper],
-  m4_esyscmd_s([test -d .git/refs/tags && (git describe --tags | sed 's/\([^\-]*\)-\([^\-]*\)-\([^\-]*\)/\1.\2+\3/g') || echo LIBMAPPER_VERSION]),
+  m4_esyscmd_s([(if git describe --tags > /dev/null; then (git describe --tags | sed 's/\([^\-]*\)-\([^\-]*\)-\([^\-]*\)/\1.\2+\3/g') else echo LIBMAPPER_VERSION; fi)]),
   [dot_mapper@googlegroups.com],[],[http://libmapper.org])
 
 # libtool version: current:revision:age