inetutils: fix build on x86_64-darwin

This is a workaround to avoid mass rebuilds in staging-next. The problem
is the 10.12 source-based SDK does not include `utmp.h`, but it should.
Another PR will fix that for the next staging cycle and revert this commit.

+6
+6
pkgs/tools/networking/inetutils/default.nix
··· 34 34 nativeBuildInputs = [ help2man perl /* for `whois' */ ]; 35 35 buildInputs = [ ncurses /* for `talk' */ libxcrypt ]; 36 36 37 + env = lib.optionalAttrs stdenv.isDarwin { 38 + # This is a temporary workaround for missing headers in the 10.12 SDK to avoid a mass rebuild. 39 + # A commit to revert this change will be included in the fix PR targeting staging. 40 + NIX_CFLAGS_COMPILE = "-Wno-error=implicit-function-declaration"; 41 + }; 42 + 37 43 # Don't use help2man if cross-compiling 38 44 # https://lists.gnu.org/archive/html/bug-sed/2017-01/msg00001.html 39 45 # https://git.congatec.com/yocto/meta-openembedded/blob/3402bfac6b595c622e4590a8ff5eaaa854e2a2a3/meta-networking/recipes-connectivity/inetutils/inetutils_1.9.1.bb#L44