clang -O2  -Wall -Wextra -Werror=implicit-function-declaration stdlib/setkey.c -o stdlib/setkey -D_GNU_SOURCE -D_BSD_SOURCE -D_ALL_SOURCE -D_DEFAULT_SOURCE  -lm  -lintl
../out/minix/basic/stdlib/setkey.o: In function `main':
stdlib/setkey.c:(.text+0x37c): undefined reference to `setkey'
clang: error: linker command failed with exit code 1 (use -v to see invocation)