[release/6.0] Disable objc_msgSend stubs in clang for compatibility with Xcode 13

Backport of dotnet#89932 and dotnet#90217 to release/6.0

Author: akoeplinger

src/libraries/Native/Unix/CMakeLists.txt

@@ -218,6 +218,17 @@ else ()
     message(FATAL_ERROR "Unknown build type. Set CMAKE_BUILD_TYPE to DEBUG or RELEASE.")
 endif ()
 
+if(CLR_CMAKE_TARGET_OSX OR CLR_CMAKE_TARGET_MACCATALYST OR CLR_CMAKE_TARGET_IOS OR CLR_CMAKE_TARGET_TVOS)
+    # Clang will by default emit objc_msgSend stubs in Xcode 14, which ld from earlier Xcodes doesn't understand.
+    # We disable this by passing -fno-objc-msgsend-selector-stubs to clang.
+    # We can probably remove this flag once we require developers to use Xcode 14.
+    # Ref: https://github.com/xamarin/xamarin-macios/issues/16223
+    check_c_compiler_flag(-fno-objc-msgsend-selector-stubs COMPILER_SUPPORTS_FNO_OBJC_MSGSEND_SELECTOR_STUBS)
+    if(COMPILER_SUPPORTS_FNO_OBJC_MSGSEND_SELECTOR_STUBS)
+        set(CLR_CMAKE_COMMON_OBJC_FLAGS "${CLR_CMAKE_COMMON_OBJC_FLAGS} -fno-objc-msgsend-selector-stubs")
+    endif()
+endif()
+
 if(CLR_CMAKE_TARGET_BROWSER)
 elseif (CLR_CMAKE_TARGET_OSX OR CLR_CMAKE_TARGET_MACCATALYST OR CLR_CMAKE_TARGET_IOS OR CLR_CMAKE_TARGET_TVOS)
     add_definitions(-D__APPLE_USE_RFC_3542)

src/libraries/Native/Unix/System.Globalization.Native/CMakeLists.txt

@@ -66,6 +66,7 @@ set(NATIVEGLOBALIZATION_SOURCES
 
 if (CLR_CMAKE_TARGET_OSX OR CLR_CMAKE_TARGET_MACCATALYST OR CLR_CMAKE_TARGET_IOS OR CLR_CMAKE_TARGET_TVOS)
     set(NATIVEGLOBALIZATION_SOURCES ${NATIVEGLOBALIZATION_SOURCES} pal_locale.m)
+    set_source_files_properties(pal_locale.m PROPERTIES COMPILE_FLAGS "${CLR_CMAKE_COMMON_OBJC_FLAGS}")
 endif()
 
 # time zone names are filtered out of icu data for the browser and associated functionality is disabled

src/libraries/Native/Unix/System.Native/CMakeLists.txt

@@ -35,26 +35,29 @@ set(NATIVE_SOURCES
 
 if (CLR_CMAKE_TARGET_OSX OR CLR_CMAKE_TARGET_MACCATALYST OR CLR_CMAKE_TARGET_IOS OR CLR_CMAKE_TARGET_TVOS)
     list (APPEND NATIVE_SOURCES pal_autoreleasepool.m)
-    set_source_files_properties(pal_autoreleasepool.m PROPERTIES COMPILE_FLAGS -fno-objc-arc)
+    set_source_files_properties(pal_autoreleasepool.m PROPERTIES COMPILE_FLAGS "-fno-objc-arc ${CLR_CMAKE_COMMON_OBJC_FLAGS}")
 else()
     list (APPEND NATIVE_SOURCES pal_autoreleasepool.c)
 endif()
 
 if (CLR_CMAKE_TARGET_MACCATALYST OR CLR_CMAKE_TARGET_IOS OR CLR_CMAKE_TARGET_TVOS)
     list (APPEND NATIVE_SOURCES pal_environment.m)
+    set_source_files_properties(pal_environment.m PROPERTIES COMPILE_FLAGS "${CLR_CMAKE_COMMON_OBJC_FLAGS}")
 else()
     list (APPEND NATIVE_SOURCES pal_environment.c)
 endif()
 
 if (CLR_CMAKE_TARGET_MACCATALYST OR CLR_CMAKE_TARGET_IOS OR CLR_CMAKE_TARGET_TVOS)
     set(NATIVE_SOURCES ${NATIVE_SOURCES}
         pal_datetime.m)
+    set_source_files_properties(pal_datetime.m PROPERTIES COMPILE_FLAGS "${CLR_CMAKE_COMMON_OBJC_FLAGS}")
 endif()
 
 if (CLR_CMAKE_TARGET_MACCATALYST OR CLR_CMAKE_TARGET_IOS OR CLR_CMAKE_TARGET_TVOS)
     set(NATIVE_SOURCES ${NATIVE_SOURCES}
         pal_log.m
         pal_searchpath.m)
+    set_source_files_properties(pal_log.m pal_searchpath.m PROPERTIES COMPILE_FLAGS "${CLR_CMAKE_COMMON_OBJC_FLAGS}")
 else ()
     list (APPEND NATIVE_SOURCES
         pal_searchpath.c
@@ -65,6 +68,7 @@ endif ()
 if (CLR_CMAKE_TARGET_MACCATALYST)
     set(NATIVE_SOURCES ${NATIVE_SOURCES}
         pal_iossupportversion.m)
+    set_source_files_properties(pal_iossupportversion.m PROPERTIES COMPILE_FLAGS "${CLR_CMAKE_COMMON_OBJC_FLAGS}")
 else ()
     list (APPEND NATIVE_SOURCES
         pal_iossupportversion.c)

src/mono/CMakeLists.txt

@@ -784,6 +784,14 @@ if (TARGET_BROWSER)
   # sys/errno.h exists, but just emits a warning and includes errno.h
   unset(HAVE_SYS_ERRNO_H)
 endif()
+
+if(TARGET_DARWIN)
+  check_c_compiler_flag(-fno-objc-msgsend-selector-stubs COMPILER_SUPPORTS_FNO_OBJC_MSGSEND_SELECTOR_STUBS)
+  if(COMPILER_SUPPORTS_FNO_OBJC_MSGSEND_SELECTOR_STUBS)
+    set(CLR_CMAKE_COMMON_OBJC_FLAGS "${CLR_CMAKE_COMMON_OBJC_FLAGS} -fno-objc-msgsend-selector-stubs")
+  endif()
+endif()
+
 ### End of OS specific checks
 
 add_subdirectory(mono)

src/mono/mono/mini/CMakeLists.txt

@@ -89,6 +89,9 @@ if(HAVE_SYS_ICU)
   addprefix(icu_shim_sources "${ICU_SHIM_PATH}" "${icu_shim_sources_base}")
   set_source_files_properties(${icu_shim_sources} PROPERTIES COMPILE_DEFINITIONS OSX_ICU_LIBRARY_PATH="${OSX_ICU_LIBRARY_PATH}")
   set_source_files_properties(${icu_shim_sources} PROPERTIES COMPILE_FLAGS "-I\"${ICU_INCLUDEDIR}\" -I\"${CMAKE_CURRENT_SOURCE_DIR}/../../../libraries/Native/Unix/System.Globalization.Native/\" -I\"${CMAKE_CURRENT_SOURCE_DIR}/../../../libraries/Native/Unix/Common/\" ${ICU_FLAGS}")
+  if(TARGET_DARWIN)
+    set_property(SOURCE "${ICU_SHIM_PATH}/pal_locale.m" APPEND_STRING PROPERTY COMPILE_FLAGS "${CLR_CMAKE_COMMON_OBJC_FLAGS}")
+  endif()
   if(TARGET_WIN32)
       set_source_files_properties(${icu_shim_sources} PROPERTIES LANGUAGE CXX)
   endif()