add heap region check to cfree

src/alloc-posix.c

@@ -38,7 +38,9 @@ size_t mi_malloc_usable_size(const void *p) mi_attr_noexcept {
 }
 
 void mi_cfree(void* p) mi_attr_noexcept {
-  mi_free(p);
+  if (mi_is_in_heap_region(p)) {
+    mi_free(p);
+  }
 }
 
 int mi_posix_memalign(void** p, size_t alignment, size_t size) mi_attr_noexcept {

src/memory.c

@@ -106,6 +106,7 @@ static size_t mi_good_commit_size(size_t size) {
 
 // Return if a pointer points into a region reserved by us.
 bool mi_is_in_heap_region(const void* p) mi_attr_noexcept {
+  if (p==NULL) return false;
   size_t count = mi_atomic_read(&regions_count);
   for (size_t i = 0; i < count; i++) {
     uint8_t* start = (uint8_t*)mi_atomic_read_ptr(&regions[i].start);