[PATCH][libstdc++-v3 parallel mode] Fix small memory leak in loser tree

[Paolo Carlini]

Hi,

> Please approve for mainline and gcc-4_3-branch.

Ok, thanks. Please fix the ChangeLog entry, however: after the file name, first the complete class member name (LoserTreePointerBase<>::~LoserTreePointerBase), then colon and the description.

Paolo.