Gentoo's Bugzilla –
Attachment 577440 Details for
Bug 686420net-analyzer/hydra USE=subversion - In file included from /usr/include/subversion-1/svn_client.h:34, from hydra-svn.c:9: /usr/include/apr-1/apr.h:632:2: error: #error no decision has been made on APR_PATH_MAX for your platform