--- libmalloc/libmalloc-374.60.3/xcodeconfig/libmalloc.xcconfig
+++ libmalloc/libmalloc-166.251.2/xcodeconfig/libmalloc.xcconfig
@@ -4,25 +4,13 @@
 SUPPORTED_PLATFORMS = macosx iphoneos iphonesimulator appletvos appletvsimulator watchos watchsimulator
 BUILD_VARIANTS = normal debug
 
-SDK_INSTALL_VARIANT = $(SDK_INSTALL_VARIANT_$(DRIVERKIT))
-SDK_INSTALL_VARIANT_1 = driverkit
-SDK_INSTALL_VARIANT_ = default
-SDK_INSTALL_ROOT = $(SDK_INSTALL_ROOT_$(SDK_INSTALL_VARIANT))
-SDK_INSTALL_ROOT_driverkit = $(DRIVERKITROOT)
-SDK_INSTALL_HEADERS_ROOT = $(SDK_INSTALL_HEADERS_ROOT_$(SDK_INSTALL_VARIANT))
-SDK_INSTALL_HEADERS_ROOT_driverkit = $(SDK_INSTALL_ROOT)/$(SDK_RUNTIME_HEADERS_PREFIX)
-SDK_RUNTIME_HEADERS_PREFIX = Runtime
+PRODUCT_NAME = libsystem_malloc
+INSTALL_PATH = /usr/lib/system
+PUBLIC_HEADERS_FOLDER_PATH = /usr/include/malloc
+PRIVATE_HEADERS_FOLDER_PATH = /usr/local/include
 
-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
-
-SYSTEM_FRAMEWORK_HEADERS = $(SDKROOT)/$(SDK_INSTALL_HEADERS_ROOT)/System/Library/Frameworks/System.framework/PrivateHeaders
-HEADER_SEARCH_PATHS = $(DERIVED_FILES_DIR)/dtrace $(SRCROOT)/include $(SRCROOT)/private $(SRCROOT)/resolver $(inherited)
-SYSTEM_HEADER_SEARCH_PATHS = $(SYSTEM_FRAMEWORK_HEADERS) $(SDKROOT)/$(SDK_INSTALL_HEADERS_ROOT)/usr/local/include $(SDKROOT)/$(SDK_INSTALL_HEADERS_ROOT)/usr/include
-SYSTEM_FRAMEWORK_SEARCH_PATHS = $(SDKROOT)/$(SDK_INSTALL_HEADERS_ROOT)/System/Library/Frameworks
+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)
 
 GCC_PREPROCESSOR_DEFINITIONS = _FORTIFY_SOURCE=0 NDEBUG $(OSATOMIC_PREPROCESSOR_DEFINITIONS) $(PLATFORM_PREPROCESSOR_DEFINITIONS)
 OSATOMIC_PREPROCESSOR_DEFINITIONS = OSATOMIC_USE_INLINED=1 OS_UNFAIR_LOCK_INLINE=1
@@ -58,7 +46,7 @@
 CLANG_WARN__DUPLICATE_METHOD_MATCH = YES
 
 // clang doesn't understand the simple_printf %y specifier
-WARNING_CFLAGS = -Wno-format-invalid-specifier -Wno-format-extra-args -Watomic-implicit-seq-cst
+WARNING_CFLAGS = -Wno-format-invalid-specifier -Wno-format-extra-args
 
 LLVM_LTO = LLVM_LTO_$(CURRENT_VARIANT)
 LLVM_LTO_normal = YES
@@ -69,29 +57,22 @@
 
 SIM_SUFFIX[sdk=*simulator*] = _sim
 LINK_WITH_STANDARD_LIBRARIES = NO
-OTHER_LDFLAGS = -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)
+OTHER_LDFLAGS = -all_load -L/usr/lib/system -umbrella System $(CR_LDFLAGS) $(LIBCOMPILER_RT_LDFLAGS) $(LIBDYLD_LDFLAGS) $(LIBSYSCALL_LDFLAGS) $(LIBPLATFORM_LDFLAGS) $(PLATFORM_LDFLAGS) $(UPLINK_LDFLAGS) $(INTERPOSE_LDFLAGS) $(DIRTY_LDFLAGS)
 LIBCOMPILER_RT_LDFLAGS = -lcompiler_rt
 LIBPLATFORM_LDFLAGS = -lsystem$(SIM_SUFFIX)_platform
 LIBSYSCALL_LDFLAGS = -lsystem$(SIM_SUFFIX)_kernel
-LIBPTHREAD_LDFLAGS = -lsystem$(SIM_SUFFIX)_pthread
 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
-
-EXCLUDED_SOURCE_FILE_NAMES = $(LIBFEATUREFLAGS_EXCLUDES)
 
 // TODO: Eliminate the crosslink between libmalloc and Libc (13046853)
 UPLINK_LDFLAGS = -Wl,-upward-lsystem_c
 
 INTERPOSE_LDFLAGS = -Wl,-interposable_list,$(SRCROOT)/xcodeconfig/interposable.list
 
+ORDER_FILE = $(SDKROOT)/$(APPLE_INTERNAL_DIR)/OrderFiles/$(PRODUCT_NAME).order
+ORDER_FILE[sdk=*simulator*] =
+
+DIRTY_LDFLAGS = -Wl,-dirty_data_list,$(SRCROOT)/xcodeconfig/libmalloc.dirty
+DIRTY_LDFLAGS[sdk=macosx*] =
+
 DYLIB_CURRENT_VERSION = $(CURRENT_PROJECT_VERSION)
 
-
-SUPPORTS_TEXT_BASED_API = YES
-TAPI_VERIFY_MODE = Pedantic
-OTHER_TAPI_FLAGS = -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