Gentoo's Bugzilla –
Attachment 841109 Details for
Bug 885059mail-filter/mapson-3.3.1 fails to compile (CLANG-STRICTER-SYSTEM): fastmint_library.c:92:17: error: call to undeclared function SHA1_Transform; ISO C99 and later do not support implicit function declarations [-Werror,-Wimplicit-function-declaration]