Gentoo's Bugzilla –
Attachment 843181 Details for
Bug 886455sci-libs/libnova-0.16.0 fails to compile (CLANG-STRICTER-SYSTEM): parallax.c:67:2: error: call to undeclared function ln_get_earth_centre_dist; ISO C99 and later do not support implicit function declarations [-Werror,-Wimplicit-function-declaration]