ошибка при выполнении sudo apt-get -f install

Я делаю sudo apt-get -f install и получаю следующую ошибку. У меня есть еще одно продолжающееся обсуждение в здесь . Ошибка, которую я получаю после запуска apt-get -f install, приведена ниже:

Reading package lists... Done
Building dependency tree       
Reading state information... Done
Correcting dependencies... Done
The following extra packages will be installed:
  libc6 libc6:i386
Suggested packages:
  glibc-doc glibc-doc:i386 locales:i386
The following packages will be upgraded:
  libc6 libc6:i386
2 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.
733 not fully installed or removed.
Need to get 0 B/8,816 kB of archives.
After this operation, 338 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Preconfiguring packages ...
(Reading database ... 320605 files and directories currently installed.)
Preparing to unpack .../libc6_2.21-0ubuntu4.1_amd64.deb ...
De-configuring libc6:i386 (2.21-0ubuntu4) ...

LD_LIBRARY_PATH contains the traditional /lib directory,
but not the multiarch directory /lib/x86_64-linux-gnu.
It is not safe to upgrade the C library in this situation;
please remove the /lib/directory from LD_LIBRARY_PATH and
try again.

dpkg: error processing archive /var/cache/apt/archives/libc6_2.21-0ubuntu4.1_amd64.deb (--unpack):
 subprocess new pre-installation script returned error exit status 1
Preparing to unpack .../libc6_2.21-0ubuntu4.1_i386.deb ...
De-configuring libc6:amd64 (2.21-0ubuntu4) ...

LD_LIBRARY_PATH contains the traditional /lib directory,
but not the multiarch directory /lib/i386-linux-gnu.
It is not safe to upgrade the C library in this situation;
please remove the /lib/directory from LD_LIBRARY_PATH and
try again.

dpkg: error processing archive /var/cache/apt/archives/libc6_2.21-0ubuntu4.1_i386.deb (--unpack):
 subprocess new pre-installation script returned error exit status 1
Errors were encountered while processing:
 /var/cache/apt/archives/libc6_2.21-0ubuntu4.1_amd64.deb
 /var/cache/apt/archives/libc6_2.21-0ubuntu4.1_i386.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
duttasankha@sankha-PC:~$ sudo apt-get update -fmy
E: Command line option 'f' [from -fmy] is not known.
duttasankha@sankha-PC:~$ sudo apt-get update -f
E: Command line option 'f' [from -f] is not known.

У меня также есть ошибка gcc, которая еще не устранена и все еще показывает #error -- unsupported GNU version! gcc versions later than 4.9 are not supported!. Я пытаюсь Google и решить, но я очень не знаю об Ubuntu или Linux в этом отношении, и мне нужна ваша помощь. Сейчас я нахожусь в ситуации, связанной с реальным временем, и помощь будет очень признательна. Спасибо за вашу помощь.