diff --git a/compiler-rt/cmake/config-ix.cmake b/compiler-rt/cmake/config-ix.cmake
--- a/compiler-rt/cmake/config-ix.cmake
+++ b/compiler-rt/cmake/config-ix.cmake
@@ -250,7 +250,28 @@
   endif()
   set(test_cflags "")
   get_target_flags_for_arch(${arch} test_cflags)
-  list(APPEND test_cflags ${DARWIN_${platform}_CFLAGS})
+
+  if (NOT "${arch}" STREQUAL "arm64e")
+    list(APPEND test_cflags ${DARWIN_${platform}_CFLAGS})
+  else()
+    # arm64e is not currently ABI stable so we need to build for the
+    # OS version being tested. Rather than querying the device under test
+    # we use the SDK version which "should" be the same as the
+    # device under test (it is a configuration error for these not to match).
+    # FIXME(dliew): We can remove this if we build the runtimes with the appropriate
+    # deployment target for arm64e.
+    foreach (flag ${DARWIN_${platform}_CFLAGS})
+      if ("${flag}" MATCHES "^${DARWIN_${platform}_MIN_VER_FLAG}=.+")
+        # Patch flag with correct deployment target
+        set(replacement_flag "${DARWIN_${platform}_MIN_VER_FLAG}=${DARWIN_${platform}_SDK_VERSION}")
+        list(APPEND test_cflags "${replacement_flag}")
+      else()
+        # Copy through
+        list(APPEND test_cflags "${flag}")
+      endif()
+    endforeach()
+  endif()
+
   string(REPLACE ";" " " test_cflags_str "${test_cflags}")
   string(APPEND test_cflags_str "${COMPILER_RT_TEST_COMPILER_CFLAGS}")
   set(${cflags_out} "${test_cflags_str}" PARENT_SCOPE)
@@ -292,6 +313,14 @@
   find_darwin_sdk_dir(DARWIN_tvossim_SYSROOT appletvsimulator)
   find_darwin_sdk_dir(DARWIN_tvos_SYSROOT appletvos)
 
+  find_darwin_sdk_version(DARWIN_osx_SDK_VERSION macosx)
+  find_darwin_sdk_version(DARWIN_iossim_SDK_VERSION iphonesimulator)
+  find_darwin_sdk_version(DARWIN_ios_SDK_VERSION iphoneos)
+  find_darwin_sdk_version(DARWIN_watchossim_SDK_VERSION watchsimulator)
+  find_darwin_sdk_version(DARWIN_watchos_SDK_VERSION watchos)
+  find_darwin_sdk_version(DARWIN_tvossim_SDK_VERSION appletvsimulator)
+  find_darwin_sdk_version(DARWIN_tvos_SDK_VERSION appletvos)
+
   if(NOT DARWIN_osx_SYSROOT)
     message(WARNING "Could not determine OS X sysroot, trying /usr/include")
     if(EXISTS /usr/include)