The libmariadb3.symbols files is used to track the libmariadb3 ABI.

If a symbol is removed or changed, the Debian build will fail unless the same change has also explicitly been made in the libmariadb3.symbols file.

If a symbol is added, the Debian build will issue a warning like:

   dh_makeshlibs -O--parallel
	rm -f debian/libmariadb3/DEBIAN/shlibs
	echo "libmariadb 3 libmariadb3" >> debian/libmariadb3/DEBIAN/shlibs
	chmod 0644 -- debian/libmariadb3/DEBIAN/shlibs
	chown 0:0 -- debian/libmariadb3/DEBIAN/shlibs
	dpkg-gensymbols -plibmariadb3 -Idebian/libmariadb3.symbols -Pdebian/libmariadb3 -edebian/libmariadb3/usr/lib/x86_64-linux-gnu/libmariadb.so.3
  dpkg-gensymbols: warning: some new symbols appeared in the symbols file: see diff output below
  dpkg-gensymbols: warning: debian/libmariadb3/DEBIAN/symbols doesn't match completely debian/libmariadb3.symbols
  --- debian/libmariadb3.symbols (libmariadb3_10.2.32+maria~sid_amd64)
  +++ dpkg-gensymbolsUfTky5	2020-02-20 11:27:03.815551573 +0000
  @@ -12,6 +12,7 @@
    mariadb_get_charset_by_name@libmariadb_3 3.0.0
    mariadb_get_charset_by_nr@libmariadb_3 3.0.0
    mariadb_get_info@libmariadb_3 3.0.0
  + mariadb_get_infov@libmariadb_3 10.2.32+maria~sid
    mariadb_reconnect@libmariadb_3 3.0.0
    mariadb_rpl_close@libmariadb_3 3.1.0
    mariadb_rpl_fetch@libmariadb_3 3.1.0


When this happens, please add the symbol to the libmariadb3.symbols file.
Unlike the automatic diff above, don't use the server version for the symbols.

Instead use the client library version, which can be viewed with:

  $ grep 'SET(CPACK_PACKAGE_VERSION_' libmariadb/CMakeLists.txt 
  SET(CPACK_PACKAGE_VERSION_MAJOR 3)
  SET(CPACK_PACKAGE_VERSION_MINOR 1)
  SET(CPACK_PACKAGE_VERSION_PATCH 7)

In this example, the line to add would be:

  mariadb_get_infov@libmariadb_3 3.1.7


Remember to not break the ABI in a stable release!