Gentoo's Bugzilla –
Attachment 838889 Details for
Bug 883969dev-python/pyFFTW-0.13.0 fails to compile (CLANG-STRICTER-SYSTEM): fftw_plan_dft.c:2:17: error: call to undeclared function fftw_plan_dft; ISO C99 and later do not support implicit function declarations [-Werror,-Wimplicit-function-declaration]