# emerge -pv libstdc++

These are the packages that would be merged, in order:

Calculating dependencies... done!
[ebuild   R   ] virtual/libstdc++-3.3  0 kB
[ebuild   R   ] sys-libs/libstdc++-v3-3.3.4  USE="nls nptl* -build (-multilib)" 7,166 kB

Total: 2 packages (2 reinstalls), Size of downloads: 7,166 kB