I wrote a static library called libverify_passwd.a using llvm-ar-7, which use symbol getpwuid, 
getspnam and crypt. It requires special linker argument -lcrypt and -lc (if -nostdlib is specified). 
Another project of mine depend on this static library and it will be cumbersome and hard to maintain by adding -lcrypt to the Makefile of that project. Is there any way so that during the link time, the dependency can be solved automatically, or is there any other tool that simplify the maintenance of this?