The Free On-line Dictionary of Computing (30 December 2018):

malloc

   C's standard library routine for storage allocation.  It
   takes the number of bytes required and returns a pointer to a
   block of that size.  Storage is allocated from a heap which
   lies after the end of the program and data areas.  Memory
   allocated with malloc must be freed explicitly using the
   "free" routine before it can be re-used.

   gc is a storage allocator with garbage collection that is
   intended to be used as a plug-in replacement for malloc.