--- libmalloc/libmalloc-521.120.7/xcodeconfig/libmalloc.xcconfig
+++ libmalloc/libmalloc-53.1.1/xcodeconfig/libmalloc.xcconfig
@@ -1,76 +1,47 @@
 #include "<DEVELOPER_DIR>/Makefiles/CoreOS/Xcode/BSD.xcconfig"
+#include "<DEVELOPER_DIR>/AppleInternal/XcodeConfig/SimulatorSupport.xcconfig"
 
+DEAD_CODE_STRIPPING = NO
 
-#include "libmalloc_common.xcconfig"
-
-SDKROOT = macosx.internal
-SUPPORTED_PLATFORMS = macosx iphoneos iphonesimulator appletvos appletvsimulator watchos watchsimulator driverkit
+SUPPORTED_PLATFORMS = macosx iphoneos iphonesimulator iphoneosnano iphonesimulatornano
 BUILD_VARIANTS = normal debug
 
-SDK_INSTALL_ROOT[sdk=driverkit*] = $(DRIVERKITROOT)
-SDK_INSTALL_HEADERS_ROOT[sdk=driverkit*] = $(SDK_INSTALL_ROOT)/$(SDK_RUNTIME_HEADERS_PREFIX)
-SDK_RUNTIME_HEADERS_PREFIX = Runtime
+OTHER_CFLAGS = -fdollars-in-identifiers -fno-common
+OTHER_CFLAGS_debug = -fstack-protector -fno-inline -O0 -DDEBUG=1
 
-PRODUCT_NAME = libsystem_malloc
-INSTALL_PATH = $(SDK_INSTALL_ROOT)/usr/lib/system
-PUBLIC_HEADERS_FOLDER_PATH = $(SDK_INSTALL_HEADERS_ROOT)/usr/include/malloc
-PRIVATE_HEADERS_FOLDER_PATH = $(SDK_INSTALL_HEADERS_ROOT)/usr/local/include
-USE_HEADERMAP = NO
+//GCC_WARN_ABOUT_MISSING_PROTOTYPES = YES
+GCC_WARN_UNUSED_FUNCTION = YES
+GCC_WARN_UNUSED_LABEL = YES
+//GCC_WARN_UNUSED_PARAMETER = YES
+GCC_WARN_UNUSED_VALUE = YES
+GCC_WARN_UNUSED_VARIABLE = YES
 
-SYSTEM_FRAMEWORK_HEADERS = $(inherited) $(SDKROOT)/$(SDK_INSTALL_HEADERS_ROOT)/System/Library/Frameworks/System.framework/PrivateHeaders
-HEADER_SEARCH_PATHS = $(inherited) $(DERIVED_FILES_DIR)/dtrace $(SRCROOT)/include $(SRCROOT)/private $(SRCROOT)/resolver $(inherited)
-SYSTEM_HEADER_SEARCH_PATHS = $(inherited) $(SYSTEM_FRAMEWORK_HEADERS)
-SYSTEM_HEADER_SEARCH_PATHS[sdk=driverkit*] = $(inherited)  $(SYSTEM_FRAMEWORK_HEADERS) $(SDKROOT)/$(SDK_INSTALL_HEADERS_ROOT)/usr/local/include $(SDKROOT)/$(SDK_INSTALL_HEADERS_ROOT)/usr/include
-SYSTEM_FRAMEWORK_SEARCH_PATHS[sdk=driverkit*] = $(inherited)  $(SDKROOT)/$(SDK_INSTALL_HEADERS_ROOT)/System/Library/Frameworks
+LINK_WITH_STANDARD_LIBRARIES = NO
+OTHER_LDFLAGS = -all_load -L/usr/lib/system -umbrella System $(CR_LDFLAGS) $(LIBCOMPILER_RT_LDFLAGS) $(LIBDYLD_LDFLAGS) $(LIBSYSCALL_LDFLAGS) $(LIBPLATFORM_LDFLAGS) $(UPLINK_LDFLAGS)
 
-GCC_PREPROCESSOR_DEFINITIONS = $(inherited) _FORTIFY_SOURCE=0 $(OSATOMIC_PREPROCESSOR_DEFINITIONS) $(PLATFORM_PREPROCESSOR_DEFINITIONS) $(DRIVERKIT_PREPROCESSOR_DEFINITIONS)
-OSATOMIC_PREPROCESSOR_DEFINITIONS = OSATOMIC_USE_INLINED=1 OS_UNFAIR_LOCK_INLINE=1
-OSATOMIC_PREPROCESSOR_DEFINITIONS_NOINLINE = OSATOMIC_DEPRECATED=0 OSATOMIC_USE_INLINED=0 OS_UNFAIR_LOCK_INLINE=0
-DRIVERKIT_PREPROCESSOR_DEFINITIONS[sdk=driverkit.macosx*] = MALLOC_TARGET_DK_OSX=1
-DRIVERKIT_PREPROCESSOR_DEFINITIONS[sdk=driverkit.iphoneos*] = MALLOC_TARGET_DK_IOS=1
-
-GCC_NO_COMMON_BLOCKS = YES
-ENABLE_STRICT_OBJC_MSGSEND = YES
-
-// TODO: Add -fno-stack-protector when uplink to Libc is removed
-OTHER_CFLAGS = $(inherited) $(PLATFORM_CFLAGS) -fno-typed-memory-operations
-OTHER_CFLAGS_normal = $(inherited) -momit-leaf-frame-pointer
-
-LLVM_LTO = LLVM_LTO_$(CURRENT_VARIANT)
-LLVM_LTO_normal = YES
-DEAD_CODE_STRIPPING = NO
-
-IS_ZIPPERED = YES
-
-SIM_SUFFIX[sdk=*simulator*] = _sim
-LINK_WITH_STANDARD_LIBRARIES = NO
-OTHER_LDFLAGS = $(inherited) -all_load -L$(SDK_INSTALL_ROOT)/usr/lib/system -umbrella System $(CR_LDFLAGS) $(LIBCOMPILER_RT_LDFLAGS) $(LIBDYLD_LDFLAGS) $(LIBSYSCALL_LDFLAGS) $(LIBPLATFORM_LDFLAGS) $(PLATFORM_LDFLAGS) $(LIBPTHREAD_LDFLAGS) $(LIBFEATUREFLAGS_LDFLAGS) $(UPLINK_LDFLAGS) $(INTERPOSE_LDFLAGS) $(DIRTY_LDFLAGS)
+CR_LDFLAGS = -lCrashReporterClient
 LIBCOMPILER_RT_LDFLAGS = -lcompiler_rt
-LIBPLATFORM_LDFLAGS = -lsystem$(SIM_SUFFIX)_platform
-LIBSYSCALL_LDFLAGS = -lsystem$(SIM_SUFFIX)_kernel
-LIBPTHREAD_LDFLAGS = -lsystem$(SIM_SUFFIX)_pthread
+LIBPLATFORM_LDFLAGS = -lsystem_platform
+LIBPLATFORM_LDFLAGS[sdk=iphonesimulator*] = -lsystem_sim_platform
+LIBSYSCALL_LDFLAGS = -lsystem_kernel
+LIBSYSCALL_LDFLAGS[sdk=iphonesimulator*] = -lsystem_sim_kernel
 LIBDYLD_LDFLAGS = -ldyld
 
-LIBFEATUREFLAGS_LDFLAGS = -Wl,-upward-lsystem_featureflags
-LIBFEATUREFLAGS_LDFLAGS[sdk=macosx*][arch=i386] =
-LIBFEATUREFLAGS_LDFLAGS[sdk=driverkit*] =
-LIBFEATUREFLAGS_EXCLUDES =
-LIBFEATUREFLAGS_EXCLUDES[sdk=driverkit*] = libmalloc.plist
+// TODO: Eliminate the crosslink between libmalloc and Libc (stdio for stack logging, spinlocks)
+UPLINK_LDFLAGS = -Wl,-upward-lsystem_c
+UPLINK_LDFLAGS[sdk=iphonesimulator*] = -Wl,-upward-lsystem_sim_c
 
-EXCLUDED_SOURCE_FILE_NAMES = $(LIBFEATUREFLAGS_EXCLUDES)
-
-// TODO: Eliminate the crosslink between libmalloc and Libc (13046853)
-// The blocks runtime is safe for use only in the context of introspection
-// logic, which isn't really in the same layer as the rest of libmalloc
-UPLINK_LDFLAGS = -Wl,-upward-lsystem_c -Wl,-upward-lsystem_blocks
-
-INTERPOSE_LDFLAGS = -Wl,-interposable_list,$(SRCROOT)/xcodeconfig/interposable.list
+ORDER_FILE = $(SDKROOT)/$(APPLE_INTERNAL_DIR)/OrderFiles/$(PRODUCT_NAME).order
+ORDER_FILE[sdk=iphonesimulator*] =
 
 DYLIB_CURRENT_VERSION = $(CURRENT_PROJECT_VERSION)
 
+PRODUCT_NAME = libsystem_malloc
+PUBLIC_HEADERS_FOLDER_PATH = $(INSTALL_PATH_PREFIX)/usr/include/malloc
+PRIVATE_HEADERS_FOLDER_PATH = $(INSTALL_PATH_PREFIX)/usr/local/include
 
-SUPPORTS_TEXT_BASED_API = YES
-TAPI_VERIFY_MODE = Pedantic
-OTHER_TAPI_FLAGS = $(inherited) -umbrella System -extra-private-header $(SRCROOT)/private/make_tapi_happy.h -extra-private-header $(SRCROOT)/src/frozen_malloc.h -extra-private-header $(SRCROOT)/private/stack_logging.h -extra-private-header $(SRCROOT)/private/malloc_implementation.h
+INSTALL_PATH_ACTUAL = /usr/lib/system
+INSTALL_PATH[sdk=macosx*] = $(INSTALL_PATH_ACTUAL)
 
-
+SYSTEM_FRAMEWORK_HEADERS = $(SDKROOT)/System/Library/Frameworks/System.framework/PrivateHeaders
+HEADER_SEARCH_PATHS = $(DERIVED_FILES_DIR)/dtrace $(SRCROOT)/include $(SYSTEM_FRAMEWORK_HEADERS) $(SDKROOT)/usr/local/include $(inherited)