The libtool current:revision:age numbers change from 6:0:2 to 6:1:2 since
no new APIs were added, changed or removed (but the source code did change).
Details:
http://www.gnu.org/software/libtool/manual/libtool.html#Updating-version-info
This changes the library filename (e.g. on Linux) from
libsigrokdecode.so.4.2.0 to libsigrokdecode.so.4.2.1, the SONAME
(+symlink) remains the same, though (libsigrokdecode.so.4).
# The algorithm for determining which number to change (and how) is nontrivial!
# http://www.gnu.org/software/libtool/manual/libtool.html#Updating-version-info
# Format: current:revision:age.
-SR_LIB_VERSION_SET([SRD_LIB_VERSION], [6:0:2])
+SR_LIB_VERSION_SET([SRD_LIB_VERSION], [6:1:2])
AM_CONDITIONAL([WIN32], [test -z "${host_os##mingw*}" || test -z "${host_os##cygwin*}"])