Comment 3 for bug 1512992

I'm encountering the same bug on xubuntu-15.10:

$ sudo apt-get upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt-get -f install' to correct these.
The following packages have unmet dependencies:
 libpng12-dev:i386 : Depends: zlib1g-dev:i386 but it is not installed
E: Unmet dependencies. Try using -f.

$ sudo apt-get -f upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Correcting dependencies... Done
Calculating upgrade... The following packages were automatically installed and are no longer required:
  appmenu-qt appmenu-qt5 apturl apturl-common bamfdaemon brasero brasero-cdrkit empathy-common folks-common gedit-common gir1.2-accounts-1.0
  gir1.2-gdata-0.0 gir1.2-goa-1.0 gir1.2-gtksource-3.0 gir1.2-signon-1.0 gir1.2-totem-1.0 gir1.2-totem-plparser-1.0 indicator-appmenu
  indicator-printers jayatana libavahi-gobject0 libbamf3-2 libchamplain-0.12-0 libedataserverui-1.2-1 libfolks-eds25 libfolks25 libframe6
  libgail-3-0 libgeis1 libglewmx1.10 libgrail6 libmission-control-plugins0 libnux-4.0-0 libnux-4.0-common libtelepathy-farstream3
  libtelepathy-logger3 libunity-core-6.0-9 libunity-gtk2-parser0 libunity-gtk3-parser0 libunity-misc4 libwhoopsie-preferences0 nux-tools
  python3-feedparser signon-plugin-password telepathy-gabble telepathy-haze telepathy-indicator telepathy-logger telepathy-mission-control-5
  telepathy-salut unity-gtk2-module unity-gtk3-module unity-lens-music unity-lens-photos unity-schemas unity-scope-audacious
  unity-scope-calculator unity-scope-chromiumbookmarks unity-scope-clementine unity-scope-colourlovers unity-scope-devhelp
  unity-scope-firefoxbookmarks unity-scope-gdrive unity-scope-gmusicbrowser unity-scope-gourmet unity-scope-guayadeque unity-scope-home
  unity-scope-manpages unity-scope-musicstores unity-scope-musique unity-scope-openclipart unity-scope-texdoc unity-scope-tomboy
  unity-scope-virtualbox unity-scope-yelp unity-scope-zotero unity-scopes-master-default unity-scopes-runner unity-services
  whoopsie-preferences
Use 'apt-get autoremove' to remove them.
Done
The following NEW packages will be installed:
  zlib1g-dev:i386
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
1 not fully installed or removed.
Need to get 0 B/167 kB of archives.
After this operation, 403 kB of additional disk space will be used.
Do you want to continue? [Y/n] Y
(Reading database ... 261971 files and directories currently installed.)
Preparing to unpack .../zlib1g-dev_1%3a1.2.8.dfsg-2ubuntu4_i386.deb ...
Unpacking zlib1g-dev:i386 (1:1.2.8.dfsg-2ubuntu4) ...
dpkg: error processing archive /var/cache/apt/archives/zlib1g-dev_1%3a1.2.8.dfsg-2ubuntu4_i386.deb (--unpack):
 trying to overwrite '/usr/include/i386-linux-gnu/zconf.h', which is also in package lib32z1-dev 1:1.2.8.dfsg-2ubuntu4
Processing triggers for man-db (2.7.4-1) ...
Errors were encountered while processing:
 /var/cache/apt/archives/zlib1g-dev_1%3a1.2.8.dfsg-2ubuntu4_i386.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

-> is there a way to repair my packages?