--- libmalloc/libmalloc-317.100.9/xcodeconfig/libmalloc.xcconfig
+++ libmalloc/libmalloc-283.100.5/xcodeconfig/libmalloc.xcconfig
@@ -58,7 +58,7 @@
 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
@@ -69,20 +69,11 @@
 
 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) $(DIRTY_LDFLAGS)
+OTHER_LDFLAGS = -all_load -L$(SDK_INSTALL_ROOT)/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