diff --git a/compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake b/compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake
--- a/compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake
+++ b/compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake
@@ -113,25 +113,23 @@
   endif()
 
   set(archs ${ARGN})
-  if(NOT TEST_COMPILE_ONLY)
-    message(STATUS "Finding valid architectures for ${os}...")
-    set(SIMPLE_C ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/src.c)
-    file(WRITE ${SIMPLE_C} "#include <stdio.h>\nint main() { printf(__FILE__); return 0; }\n")
-
-    set(os_linker_flags)
-    foreach(flag ${DARWIN_${os}_LINK_FLAGS})
-      set(os_linker_flags "${os_linker_flags} ${flag}")
-    endforeach()
+  message(STATUS "Finding valid architectures for ${os}...")
+  set(SIMPLE_C ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/src.c)
+  file(WRITE ${SIMPLE_C} "#include <stdio.h>\nint main() { printf(__FILE__); return 0; }\n")
 
-    # Disable building for i386 for macOS SDK >= 10.15. The SDK doesn't support
-    # linking for i386 and the corresponding OS doesn't allow running macOS i386
-    # binaries.
-    if ("${os}" STREQUAL "osx")
-      find_darwin_sdk_version(macosx_sdk_version "macosx")
-      if ("${macosx_sdk_version}" VERSION_GREATER 10.15 OR "${macosx_sdk_version}" VERSION_EQUAL 10.15)
-        message(STATUS "Disabling i386 slice for ${valid_archs}")
-        list(REMOVE_ITEM archs "i386")
-      endif()
+  set(os_linker_flags)
+  foreach(flag ${DARWIN_${os}_LINK_FLAGS})
+    set(os_linker_flags "${os_linker_flags} ${flag}")
+  endforeach()
+
+  # Disable building for i386 for macOS SDK >= 10.15. The SDK doesn't support
+  # linking for i386 and the corresponding OS doesn't allow running macOS i386
+  # binaries.
+  if ("${os}" STREQUAL "osx")
+    find_darwin_sdk_version(macosx_sdk_version "macosx")
+    if ("${macosx_sdk_version}" VERSION_GREATER 10.15 OR "${macosx_sdk_version}" VERSION_EQUAL 10.15)
+      message(STATUS "Disabling i386 slice for ${valid_archs}")
+      list(REMOVE_ITEM archs "i386")
     endif()
   endif()
 
@@ -146,17 +144,12 @@
   foreach(arch ${archs})
    
     set(arch_linker_flags "-arch ${arch} ${os_linker_flags}")
-    if(TEST_COMPILE_ONLY)
-      # `-w` is used to surpress compiler warnings which `try_compile_only()` treats as an error.
-      try_compile_only(CAN_TARGET_${os}_${arch} FLAGS -v -arch ${arch} ${DARWIN_${os}_CFLAGS} -w)
-    else()
-      set(SAVED_CMAKE_EXE_LINKER_FLAGS ${CMAKE_EXE_LINKER_FLAGS})
-      set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${arch_linker_flags}")
-      try_compile(CAN_TARGET_${os}_${arch} ${CMAKE_BINARY_DIR} ${SIMPLE_C}
-                  COMPILE_DEFINITIONS "-v -arch ${arch}" ${DARWIN_${os}_CFLAGS}
-                  OUTPUT_VARIABLE TEST_OUTPUT)
-      set(CMAKE_EXE_LINKER_FLAGS ${SAVED_CMAKE_EXE_LINKER_FLAGS})
-    endif()
+    set(SAVED_CMAKE_EXE_LINKER_FLAGS ${CMAKE_EXE_LINKER_FLAGS})
+    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${arch_linker_flags}")
+    try_compile(CAN_TARGET_${os}_${arch} ${CMAKE_BINARY_DIR} ${SIMPLE_C}
+                COMPILE_DEFINITIONS "-v -arch ${arch}" ${DARWIN_${os}_CFLAGS}
+                OUTPUT_VARIABLE TEST_OUTPUT)
+    set(CMAKE_EXE_LINKER_FLAGS ${SAVED_CMAKE_EXE_LINKER_FLAGS})
     if(${CAN_TARGET_${os}_${arch}})
       list(APPEND working_archs ${arch})
     else()
diff --git a/compiler-rt/cmake/builtin-config-ix.cmake b/compiler-rt/cmake/builtin-config-ix.cmake
--- a/compiler-rt/cmake/builtin-config-ix.cmake
+++ b/compiler-rt/cmake/builtin-config-ix.cmake
@@ -115,7 +115,7 @@
     set(DARWIN_ios_BUILTIN_MIN_VER_FLAG
       ${DARWIN_ios_MIN_VER_FLAG}=${DARWIN_ios_BUILTIN_MIN_VER})
     set(DARWIN_ios_BUILTIN_ALL_POSSIBLE_ARCHS ${ARM64} ${ARM32})
-    set(DARWIN_iossim_BUILTIN_ALL_POSSIBLE_ARCHS ${X86} ${X86_64})
+    set(DARWIN_iossim_BUILTIN_ALL_POSSIBLE_ARCHS ${X86} ${X86_64} arm64)
   endif()
   if(COMPILER_RT_ENABLE_WATCHOS)
     list(APPEND DARWIN_EMBEDDED_PLATFORMS watchos)
@@ -124,7 +124,7 @@
     set(DARWIN_watchos_BUILTIN_MIN_VER_FLAG
       ${DARWIN_watchos_MIN_VER_FLAG}=${DARWIN_watchos_BUILTIN_MIN_VER})
     set(DARWIN_watchos_BUILTIN_ALL_POSSIBLE_ARCHS armv7 armv7k arm64_32)
-    set(DARWIN_watchossim_BUILTIN_ALL_POSSIBLE_ARCHS ${X86})
+    set(DARWIN_watchossim_BUILTIN_ALL_POSSIBLE_ARCHS ${X86} ${X86_64} arm64)
   endif()
   if(COMPILER_RT_ENABLE_TVOS)
     list(APPEND DARWIN_EMBEDDED_PLATFORMS tvos)
@@ -133,7 +133,7 @@
     set(DARWIN_tvos_BUILTIN_MIN_VER_FLAG
       ${DARWIN_tvos_MIN_VER_FLAG}=${DARWIN_tvos_BUILTIN_MIN_VER})
     set(DARWIN_tvos_BUILTIN_ALL_POSSIBLE_ARCHS armv7 arm64)
-    set(DARWIN_tvossim_BUILTIN_ALL_POSSIBLE_ARCHS ${X86} ${X86_64})
+    set(DARWIN_tvossim_BUILTIN_ALL_POSSIBLE_ARCHS ${X86} ${X86_64} arm64)
   endif()
 
   set(BUILTIN_SUPPORTED_OS osx)