It is fairly common in Debian that some package compiled a long time ago still depend on older versions of libraries. A rebuild will some times update the dependency to a more recent library, but this is not done automatically. As a test, I wrote a script to detect such library redundancy on the Debian Edu ISO. It is available in svn as rc/build/CD-administrator/find-dup-libs. Having multiple versions of a library on the ISO (and on disk) uses extra space, and if a simple rebuild would avoid it the space can be seen as wasted.
When running it on the stretch usbstick ISO file list, I get this output with libraries where several versions are on the ISO: cpp- cpp-4.8 cpp-4.9 gcc- gcc-4.8 gcc-4.9 gir1.2-gst-plugins-base- gir1.2-gst-plugins-base-0.10 gir1.2-gst-plugins-base-1.0 gir1.2-gstreamer- gir1.2-gstreamer-0.10 gir1.2-gstreamer-1.0 gir1.2-gtk- gir1.2-gtk-2.0 gir1.2-gtk-3.0 libasan libasan0 libasan1 libass libass4 libass5 libattica libattica0 libattica0.4 libavcodec libavcodec53 libavcodec56 libavdevice libavdevice53 libavdevice55 libavfilter libavfilter2 libavfilter5 libavformat libavformat53 libavformat56 libavutil libavutil51 libavutil54 libbluedevil libbluedevil1 libbluedevil2 libcamel-1.2- libcamel-1.2-33 libcamel-1.2-49 libcdt libcdt4 libcdt5 libcfitsio libcfitsio2 libcfitsio3 libcgraph libcgraph5 libcgraph6 libcheese libcheese3 libcheese7 libcogl libcogl20 libcogl9 libcogl-pango libcogl-pango0 libcogl-pango20 libcolord libcolord1 libcolord2 libcsound64- libcsound64-5.2 libcsound64-6.0 libdb libdb5.1 libdb5.3 libdconf libdconf0 libdconf1 libdns libdns100 libdns88 libdotconf libdotconf0 libdotconf1.0 libdvbpsi libdvbpsi7 libdvbpsi9 libebml libebml3 libebml4 libecal-1.2- libecal-1.2-11 libecal-1.2-16 libedataserver-1.2- libedataserver-1.2-16 libedataserver-1.2-18 libepsilon libepsilon0 libepsilon1 libexiv2- libexiv2-12 libexiv2-13 libfltk libfltk1.1 libfltk1.3 libfm libfm1 libfm4 libfm-gtk libfm-gtk1 libfm-gtk4 libgcj libgcj13 libgcj15 libgcrypt libgcrypt11 libgcrypt20 libgdata libgdata13 libgdata19 libgeos- libgeos-3.3.3 libgeos-3.4.2 libglew libglew1.10 libglew1.7 libgmlib libgmlib0 libgmlib1 libgmtk libgmtk0 libgmtk1 libgnome-bluetooth libgnome-bluetooth10 libgnome-bluetooth13 libgnome-desktop-3- libgnome-desktop-3-10 libgnome-desktop-3-2 libgphoto2- libgphoto2-2 libgphoto2-6 libgphoto2-port libgphoto2-port0 libgphoto2-port10 libgps libgps20 libgps21 libgraphite2- libgraphite2-2.0.0 libgraphite2-3 libgtksourceview-3.0- libgtksourceview-3.0-0 libgtksourceview-3.0-1 libgvpr libgvpr1 libgvpr2 libhd libhd16 libhd21 libhdf5- libhdf5-7 libhdf5-8 libicu libicu48 libicu52 libiscsi libiscsi1 libiscsi2 libkexiv2- libkexiv2-10 libkexiv2-11 libkipi libkipi11 libkipi8 libkwineffects1abi libkwineffects1abi3 libkwineffects1abi5 libkworkspace4abi libkworkspace4abi1 libkworkspace4abi2 liblept liblept3 liblept4 libmarblewidget libmarblewidget13 libmarblewidget19 libmatroska libmatroska5 libmatroska6 libmenu-cache libmenu-cache1 libmenu-cache3 libmikmod libmikmod2 libmikmod3 libminiupnpc libminiupnpc10 libminiupnpc5 libmlt libmlt5 libmlt6 libmpc libmpc2 libmpc3 libmpeg3- libmpeg3-1 libmpeg3-2 libobrender libobrender27 libobrender29 libobt libobt0 libobt2 libokularcore libokularcore1 libokularcore5 libopenjpeg libopenjpeg2 libopenjpeg5 libortp libortp8 libortp9 libotr libotr2 libotr5 libpackagekit-glib2- libpackagekit-glib2-14 libpackagekit-glib2-18 libplasmaclock4abi libplasmaclock4abi3 libplasmaclock4abi4 libplist libplist1 libplist2 libpoppler libpoppler19 libpoppler46 libpoppler-qt4- libpoppler-qt4-3 libpoppler-qt4-4 libprocps libprocps0 libprocps3 libprotobuf libprotobuf7 libprotobuf9 libprotoc libprotoc7 libprotoc9 libpython libpython2.7 libpython3.4 libreadline libreadline5 libreadline6 librtaudio librtaudio4 librtaudio5 librtmp librtmp0 librtmp1 libruby libruby1.8 libruby2.1 libsidplay libsidplay1 libsidplay2 libswscale libswscale2 libswscale3 libtasn1- libtasn1-3 libtasn1-6 libtcl libtcl8.5 libtcl8.6 libticables2- libticables2-1 libticables2-6 libticalcs2- libticalcs2-11 libticalcs2-7 libticonv libticonv3 libticonv7 libtiff libtiff4 libtiff5 libtk libtk8.5 libtk8.6 libusbmuxd libusbmuxd1 libusbmuxd2 libwiretap libwiretap2 libwiretap4 libx264- libx264-123 libx264-142 ruby ruby1.8 ruby2.1 tcl tcl8.5 tcl8.6 tk tk8.5 tk8.6 python python2.7 python3 python3.4 Not quite sure how to avoid this without rebuilding the entire archive before a new release. -- Happy hacking Petter Reinholdtsen
