https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67097
--- Comment #6 from Gilles Gouaillardet <gilles.gouaillardet at gmail dot com> --- as a side note, would you be interested in me providing a patch so gcov-tool merge can merge n directories (currently, we are limited to n=2) ? i would implement that via a binary tree, so under the hood, that would require o(log(n)) elementary merge of two directories. for extreme merge, i can also add an option that specifies the temporary directory to be used (e.g. something different that /tmp/$TMPDIR)