--- libmalloc/libmalloc-409.81.2/src/platform.h
+++ libmalloc/libmalloc-283/src/platform.h
@@ -24,11 +24,11 @@
 #ifndef __PLATFORM_H
 #define __PLATFORM_H
 
-#if (TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR) || (TARGET_OS_DRIVERKIT && !MALLOC_TARGET_DK_OSX)
+#if TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR
 #define MALLOC_TARGET_IOS 1
-#else // (TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR) || (TARGET_OS_DRIVERKIT && !MALLOC_TARGET_DK_OSX)
+#else // TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR
 #define MALLOC_TARGET_IOS 0
-#endif // (TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR) || (TARGET_OS_DRIVERKIT && !MALLOC_TARGET_DK_OSX)
+#endif // TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR
 
 #ifdef __LP64__
 #define MALLOC_TARGET_64BIT 1
@@ -44,13 +44,12 @@
 #endif // MALLOC_TARGET_IOS
 
 // <rdar://problem/12596555>
-#define CONFIG_RECIRC_DEPOT 1
-#define CONFIG_AGGRESSIVE_MADVISE 1
-
 #if MALLOC_TARGET_IOS
-# define DEFAULT_AGGRESSIVE_MADVISE_ENABLED true
+# define CONFIG_RECIRC_DEPOT 1
+# define CONFIG_AGGRESSIVE_MADVISE 1
 #else // MALLOC_TARGET_IOS
-# define DEFAULT_AGGRESSIVE_MADVISE_ENABLED false
+# define CONFIG_RECIRC_DEPOT 1
+# define CONFIG_AGGRESSIVE_MADVISE 0
 #endif // MALLOC_TARGET_IOS
 
 // <rdar://problem/10397726>
@@ -70,15 +69,6 @@
 // enable nano checking for corrupt free list
 #define NANO_FREE_DEQUEUE_DILIGENCE 1
 
-// Conditional behaviour depends on MallocSpaceEfficient being set by
-// JetsamProperties which isn't true on iOS
-#if MALLOC_TARGET_IOS || TARGET_OS_DRIVERKIT
-#define NANOV2_DEFAULT_MODE NANO_ENABLED
-#else
-#define NANOV2_DEFAULT_MODE NANO_CONDITIONAL
-#endif
-
-
 // This governs a last-free cache of 1 that bypasses the free-list for each region size
 #define CONFIG_TINY_CACHE 1
 #define CONFIG_SMALL_CACHE 1
@@ -96,33 +86,11 @@
 #endif // MALLOC_TARGET_64BIT
 
 // The large last-free cache (aka. death row cache)
-#if TARGET_OS_IOS || TARGET_OS_SIMULATOR || TARGET_OS_DRIVERKIT
-// sdk=iphoneos, simulator, sdk=driverkit
-#define CONFIG_LARGE_CACHE 1
-#elif MALLOC_TARGET_IOS
-// all other embedded
+#if MALLOC_TARGET_IOS
 #define CONFIG_LARGE_CACHE 0
 #else
-// Mac
 #define CONFIG_LARGE_CACHE 1
 #endif
-
-#if CONFIG_LARGE_CACHE
-
-#if MALLOC_TARGET_IOS && MALLOC_TARGET_64BIT
-#define DEFAULT_LARGE_CACHE_ENABLED false
-#define CONFIG_DEFERRED_RECLAIM 1
-
-#elif TARGET_OS_SIMULATOR || (MALLOC_TARGET_IOS && !MALLOC_TARGET_64BIT)
-#define DEFAULT_LARGE_CACHE_ENABLED false
-#define CONFIG_DEFERRED_RECLAIM 0
-
-#else // TARGET_OS_SIMULATOR || (MALLOC_TARGET_IOS && !MALLOC_TARGET_64BIT)
-#define DEFAULT_LARGE_CACHE_ENABLED true
-#define CONFIG_DEFERRED_RECLAIM 0
-
-#endif // TARGET_OS_SIMULATOR || (MALLOC_TARGET_IOS && !MALLOC_TARGET_64BIT)
-#endif // CONFIG_LARGE_CACHE
 
 #if MALLOC_TARGET_IOS
 // The VM system on iOS forces malloc-tagged memory to never be marked as
@@ -140,19 +108,6 @@
 #define ENABLE_MEMORY_RESOURCE_EXCEPTION_HANDLING 1
 #endif
 
-#if !TARGET_OS_DRIVERKIT && (!TARGET_OS_OSX || MALLOC_TARGET_64BIT)
-#define CONFIG_FEATUREFLAGS_SIMPLE 1
-#else
-#define CONFIG_FEATUREFLAGS_SIMPLE 0
-#endif
-
-// Quarantine zone, only useful on macOS (+ DriverKit, 64-bit simulators).
-#if (TARGET_OS_OSX || TARGET_OS_DRIVERKIT || TARGET_OS_SIMULATOR) && MALLOC_TARGET_64BIT
-#define CONFIG_QUARANTINE 1
-#else
-#define CONFIG_QUARANTINE 0
-#endif
-
 // presence of commpage memsize
 #define CONFIG_HAS_COMMPAGE_MEMSIZE 1
 
@@ -164,16 +119,4 @@
 #define CONFIG_TINY_USES_HYPER_SHIFT 0
 #define CONFIG_SMALL_USES_HYPER_SHIFT 0
 
-// FIXME: limit number of malloc_create_zone() wrapper zones for watchOS to remove this
-#if TARGET_OS_OSX || TARGET_OS_IOS
-#define CONFIG_PGM_WRAP_CUSTOM_ZONES 1
-#else
-#define CONFIG_PGM_WRAP_CUSTOM_ZONES 0
-#endif
-
-
-#ifndef MALLOC_ZERO_POLICY_DEFAULT
-#define MALLOC_ZERO_POLICY_DEFAULT MALLOC_ZERO_ON_FREE
-#endif
-
 #endif // __PLATFORM_H