--- libmalloc/libmalloc-521.120.7/src/nano_malloc_common.h
+++ libmalloc/libmalloc-374.40.6/src/nano_malloc_common.h
@@ -24,8 +24,12 @@
 #ifndef __NANO_MALLOC_COMMON_H
 #define __NANO_MALLOC_COMMON_H
 
-#include <malloc/_ptrcheck.h>
-__ptrcheck_abi_assume_single()
+// Definitions that are common to Nano
+#if TARGET_OS_OSX || TARGET_OS_SIMULATOR || TARGET_OS_DRIVERKIT
+#define NANO_PREALLOCATE_BAND_VM 0
+#else // TARGET_OS_OSX || TARGET_OS_SIMULATOR || TARGET_OS_DRIVERKIT
+#define NANO_PREALLOCATE_BAND_VM 1 // pre-allocate reserved vm range
+#endif // TARGET_OS_OSX || TARGET_OS_SIMULATOR || TARGET_OS_DRIVERKIT
 
 typedef enum {
 	NANO_NONE	= 0,
@@ -33,11 +37,6 @@
 } nano_version_t;
 
 // Nano malloc enabled flag
-//
-// Note that this flag indicates whether a "nano-like" configuration, i.e. one
-// that trades memory for CPU and scalability, is enabled, but not literally
-// whether the nano allocator itself is engaged.  Test for nano itself using
-// initial_nano_zone.
 MALLOC_NOEXPORT
 extern nano_version_t _malloc_engaged_nano;
 
@@ -46,11 +45,7 @@
 extern unsigned int nano_common_max_magazines;
 
 MALLOC_NOEXPORT
-extern bool nano_common_max_magazines_is_ncpu;
-
-// Index of last region to be allocated
-MALLOC_NOEXPORT
-extern unsigned int nano_max_region;
+extern boolean_t nano_common_max_magazines_is_ncpu;
 
 MALLOC_NOEXPORT
 void
@@ -58,7 +53,7 @@
 
 MALLOC_NOEXPORT
 void
-nano_common_init(const char * __null_terminated * __null_terminated envp, const char * __null_terminated * __null_terminated apple, const char *bootargs);
+nano_common_init(const char *envp[], const char *apple[], const char *bootargs);
 
 MALLOC_NOEXPORT
 void
@@ -70,16 +65,8 @@
 		unsigned debug_flags, int vm_page_label, void *base_addr);
 
 MALLOC_NOEXPORT
-bool
+boolean_t
 nano_common_allocate_vm_space(mach_vm_address_t base, mach_vm_size_t size);
-
-MALLOC_NOEXPORT
-bool
-nano_common_reserve_vm_space(mach_vm_address_t base, mach_vm_size_t size);
-
-MALLOC_NOEXPORT
-bool
-nano_common_unprotect_vm_space(mach_vm_address_t base, mach_vm_size_t size);
 
 MALLOC_NOEXPORT
 void
@@ -90,9 +77,5 @@
 nano_common_default_reader(task_t task, vm_address_t address, vm_size_t size,
 		void **ptr);
 
-MALLOC_NOEXPORT
-nano_version_t
-_nano_common_init_pick_mode(const char * __null_terminated * __null_terminated envp, const char * __null_terminated * __null_terminated apple, const char *bootargs, bool space_efficient_enabled);
-
 #endif // __NANO_MALLOC_COMMON_H