Resolvido, instalando as bibliotecas xfonts-75dpi e xfonts-100dpi depois de encontrar isto .
Ao tentar iniciar o ICEMCFD (uma ferramenta de malha para simulações de fluxo), recebo uma mensagem de erro e a analiso com LIBGL_DEBUG=verbose yields:
ldzq68@DS-ECSTL-001:/usr/ansys_inc/v121/icemcfd/linux/bin$ LIBGL_DEBUG=verbose ./icemcfd
ICEM_ACN is /usr/ansys_inc/v121/icemcfd/linux
ANSYSLIC_DIR is set to /usr/ansys_inc/shared_files/licensing
args
Window information: depth = 24
class = 4
visual depth = 24 class = 4
libGL: OpenDriver: trying /usr/lib/i386-linux-gnu/dri/tls/r600_dri.so
libGL: OpenDriver: trying /usr/lib/i386-linux-gnu/dri/r600_dri.so
libGL error: dlopen /usr/lib/i386-linux-gnu/dri/r600_dri.so failed (/usr/ansys_inc/v121/icemcfd/linux/lib/libstdc++.so.6: version 'GLIBCXX_3.4.9' not found (required by /usr/lib/i386-linux-gnu/libLLVM-3.1.so.1))
libGL: OpenDriver: trying ${ORIGIN}/dri/tls/r600_dri.so
libGL: OpenDriver: trying ${ORIGIN}/dri/r600_dri.so
libGL error: dlopen ${ORIGIN}/dri/r600_dri.so failed (${ORIGIN}/dri/r600_dri.so: cannot open shared object file: No such file or directory)
libGL: OpenDriver: trying /usr/lib/dri/tls/r600_dri.so
libGL: OpenDriver: trying /usr/lib/dri/r600_dri.so
libGL error: dlopen /usr/lib/dri/r600_dri.so failed (/usr/lib/dri/r600_dri.so: cannot open shared object file: No such file or directory)
libGL error: unable to load driver: r600_dri.so
libGL error: driver pointer missing
libGL error: failed to load driver: r600
libGL: OpenDriver: trying /usr/lib/i386-linux-gnu/dri/tls/swrast_dri.so
libGL: OpenDriver: trying /usr/lib/i386-linux-gnu/dri/swrast_dri.so
libGL error: dlopen /usr/lib/i386-linux-gnu/dri/swrast_dri.so failed (/usr/ansys_inc/v121/icemcfd/linux/lib/libstdc++.so.6: version 'GLIBCXX_3.4.9' not found (required by /usr/lib/i386-linux-gnu/libLLVM-3.1.so.1))
libGL: OpenDriver: trying ${ORIGIN}/dri/tls/swrast_dri.so
libGL: OpenDriver: trying ${ORIGIN}/dri/swrast_dri.so
libGL error: dlopen ${ORIGIN}/dri/swrast_dri.so failed (${ORIGIN}/dri/swrast_dri.so: cannot open shared object file: No such file or directory)
libGL: OpenDriver: trying /usr/lib/dri/tls/swrast_dri.so
libGL: OpenDriver: trying /usr/lib/dri/swrast_dri.so
libGL error: dlopen /usr/lib/dri/swrast_dri.so failed (/usr/lib/dri/swrast_dri.so: cannot open shared object file: No such file or directory)
libGL error: unable to load driver: swrast_dri.so
libGL error: failed to load driver: swrast
X Error of failed request: BadAlloc (insufficient resources for operation)
Major opcode of failed request: 154 (GLX)
Minor opcode of failed request: 3 (X_GLXCreateContext)
Serial number of failed request: 5496
Current serial number in output stream: 5500
Depois de ler outros tópicos eu tentei atualizar o libstdc ++ 6 e
sudo apt-get install libstdc++6
me diz que a libstdc ++ 6 já é a versão mais recente.
Então, seguindo este conselho eu atualizei minhas bibliotecas stdc ++ usando
sudo add-apt-repository ppa:ubuntu-toolchain-r/test
sudo apt-get update
sudo apt-get upgrade
sudo apt-get dist-upgrade
mas ainda recebo o mesmo erro quando quero iniciar o ICEM.