added versioning to the shared library

Author: JohnCremona

configure.ac

@@ -14,6 +14,22 @@ AM_PROG_AR
 # Initialise libtools:
 LT_INIT
 
+# The version of the libtool library is of the form current:revision:age
+#
+# When doing a release, they should be updated like this:
+# 1. If no interfaces changed, only implementations: just increment
+# revision.
+# 2. If interfaces were added, none removed: increment current, set
+# revision to zero and increment age.
+# 3. If interfaces were removed (breaks backward compatibility): increment
+# current, and set both revision and age to zero.
+LT_CURRENT=1
+LT_REVISION=0
+LT_AGE=0
+AC_SUBST(LT_CURRENT)
+AC_SUBST(LT_REVISION)
+AC_SUBST(LT_AGE)
+
 # Checks for programs:
 AC_PROG_CXX
 AC_PROG_CC

libsrc/Makefile.am

@@ -37,6 +37,6 @@ DOTCCS = $(PROCS_DOTCCS) $(QCURVES_DOTCCS) $(QRANK_DOTCCS) $(G0N_DOTCCS)
 EXTRA_DIST = vec.cc mat.cc sub.cc smat.cc svec.cc smat_elim.cc random.cc
 
 libec_la_SOURCES = $(DOTCCS)
-libec_la_LDFLAGS = -no-undefined $(AM_LDFLAGS)
+libec_la_LDFLAGS = -no-undefined $(AM_LDFLAGS) -version-info @LT_CURRENT@:@LT_REVISION@:@LT_AGE@
 nobase_include_HEADERS = $(DOTHS)
 ACLOCAL_AMFLAGS = -I m4