ParMETIS can't find malloc() in OS X

In some OS X systems, compilation of ParMETIS will stop with:

(cd ParMETISLib ; make )
mpicc -DNDEBUG -O3 -I. -c comm.c
In file included from ./parmetislib.h:19:0,
from comm.c:11:
./stdheaders.h:17:20: fatal error: malloc.h: No such file or directory
compilation terminated.
make[1]: *** [comm.o] Error 1
make: *** [default] Error 2

This is because OS X does not have a malloc.h header, and the malloc declaration is instead included in stdlib.h. This problem can be fixed by wrapping the #include call in ParMETISLib/stdheaders.h with a conditional with the following code:

#if !defined(__APPLE__)
#include <malloc.h>