GPRbuild has been re-bootstrapped on ARM, so there is now a statically linked GPRbuild in Rawhide on all three primary architectures. It seems to work well, because it can build other packages without errors. With this in place we'll be able to rebuild packages after future GCC upgrades.
The following packages have been rebuilt with GCC 6 and linked to the new libgnat:
ahven anet aws florist gnatcoll gprbuild GtkAda GtkAda3 mine_detector PragmARC templates_parser xmlada zlib-ada
A scratch build of Matreshka succeeded and the official build is now running.
Björn