libgcc

[Dr Gavin Seddon <gavin.m.seddon@man.ac.uk>]

Hi,
When I run some software I get
'Xlib:  extension "XFree86-DRI" missing on display ":0.0".
libgcc_s.so.1 must be installed for pthread_cancel to work'
the only libgcc I see is
'libgcc1'
and it says I have the latest version.  How do I fix this, please?
Gavin.