The mac compiler can't optimize out unused functions.
For some reason "configure" is explicitly NOT passing
LDOPTIMIZE="-Wl,--gc-sections" to the mac build. I don't know why,
but it means the linker includes unused functions in the binary,
and thus complains about unused dependencies being missing.
diff --git a/lib/portability.h b/lib/portability.h
index a1dd3a6..7d8334b 100644
--- a/lib/portability.h
+++ b/lib/portability.h
@@ -197,7 +197,7 @@
#include <sys/personality.h>
#else
#define PER_LINUX32 0
-void personality(int x);
+#define personality(x)
#endif
#if defined(__APPLE__) || defined(__linux__)
