Why replace libgcc1, libstc++6, et al?

I am upgrading Debian Squeeze systems from TDE 3.5.12 to 3.5.13. The upgrades seem to work fine omitting the following packages: gcc-4.5-base 4.5.2-8ubuntu4 i386 libgcc1 1:4.5.2-8ubuntu4 i386 libgfortran3 4.5.2-8ubuntu4 i386 libgomp1 4.5.2-8ubuntu4 i386 libstdc++6 4.5.2-8ubuntu4 i386 I am loathe to install non-Debian versions of these packages in case they cause problems with other Debian software, either now or in future. Is there any reason why Trinity needs to replace such critical packages? Thanks, --Mike Bird