"man 5 kde.eclass" says for function kde_src_compile (note the truncated second sentence): kde_src_compile [ myconf ] [ configure ] [ make ] [ all ] This function compiles the sources. It takes care of "cannot write to .kde or If no argument is given, all is assumed. The reason is that the corresponding line in kde.ebuild starts with "# ." and the period is interpreted by nroff as a macro.
Created attachment 167311 [details, diff] Fix for the problem.
Ulrich, thanks for the report and for the fix. Committed.