sholsapp
commented
8 years ago See https://sourceware.org/ml/libc-alpha/2011-07/msg00136.html email thread discussing why removing these hooks are considered harmful. I doubt these hooks are going anywhere, so we should just live with the error message.
These functions have been deprecated in place of declaring the symbol directly (apparently malloc is defined as a weak symbol in glibc). Check out http://stackoverflow.com/questions/17803456/an-alternative-for-the-deprecated-malloc-hook-functionality-of-glibc for a good description of the problem and how to adjust code that is using __malloc_hook.