enable system's my_malloc/calloc/realloc/free via compile time option
diff --git a/cs.c b/cs.c
index 76cab6a..284d31e 100644
--- a/cs.c
+++ b/cs.c
@@ -16,10 +16,17 @@
unsigned int all_arch = 0;
+#ifdef USE_SYS_DYN_MEM
malloc_t my_malloc = malloc;
calloc_t my_calloc = calloc;
realloc_t my_realloc = realloc;
free_t my_free = free;
+#else
+malloc_t my_malloc = NULL;
+calloc_t my_calloc = NULL;
+realloc_t my_realloc = NULL;
+free_t my_free = NULL;
+#endif
unsigned int cs_version(int *major, int *minor)
{