We should link against -lc before any of the binutils libs (libiberty/bfd)
as those libs provide replacements for some common functions we don't really
care about (like getopt). Otherwise, if the C library does something wacky
in its API (like renaming symbols), we get a desync where some symbols are
provided by the binutils libs while others are provided by the C library.
For a concrete example, try building elf2flt on OS X 10.5. Their stupid
headers do this in unistd.h: