--- a/lib/malloc.h	
+++ a/lib/malloc.h	
@@ -0,0 +1,3 @@ 
+#include <sys/types.h>
+
+void * rpl_malloc (size_t n);
--- a/lib/realloc.h	
+++ a/lib/realloc.h	
@@ -0,0 +1,3 @@ 
+#include <sys/types.h>
+
+void * rpl_realloc (void *p, size_t n);
--- a/src/config.h.in	
+++ a/src/config.h.in	
@@ -250,12 +250,14 @@ 
 #undef const
 
 /* Define to rpl_malloc if the replacement function should be used. */
+#include "rpl_malloc.h"
 #undef malloc
 
 /* Define to `int' if <sys/types.h> does not define. */
 #undef pid_t
 
 /* Define to rpl_realloc if the replacement function should be used. */
+#include "rpl_realloc.h"
 #undef realloc
 
 /* Define to `unsigned int' if <sys/types.h> does not define. */
--- a/src/rpl_malloc.h	
+++ a/src/rpl_malloc.h	
@@ -0,0 +1, @@ 
+../lib/malloc.h
--- a/src/rpl_realloc.h	
+++ a/src/rpl_realloc.h	
@@ -0,0 +1, @@ 
+../lib/realloc.h