[llvm][objdump] Remove support for printing the embedded Bitcode section in MachO files. (#68457)

It's no longer possible to submit bitcode apps to the Apple App Store.
The tools
used to create xar archived bitcode sections inside MachO files have
been
discontinued. Additionally, the xar APIs have been deprecated since
macOS 12,
so this change removes unnecessary code from objdump and all
dependencies on
libxar.

This fixes rdar://116600767

Author: ributzka

llvm/cmake/config-ix.cmake

@@ -252,17 +252,6 @@ else()
   set(LLVM_ENABLE_TERMINFO 0)
 endif()
 
-check_library_exists(xar xar_open "" LLVM_HAVE_LIBXAR)
-if(LLVM_HAVE_LIBXAR)
-  message(STATUS "The xar file format has been deprecated: LLVM_HAVE_LIBXAR might be removed in the future.")
-  # The xar file format has been deprecated since macOS 12.0.
-  if (CMAKE_OSX_DEPLOYMENT_TARGET VERSION_GREATER_EQUAL 12)
-    set(LLVM_HAVE_LIBXAR 0)
-  else()
-    set(XAR_LIB xar)
-  endif()
-endif()
-
 # function checks
 check_symbol_exists(arc4random "stdlib.h" HAVE_DECL_ARC4RANDOM)
 find_package(Backtrace)

llvm/cmake/modules/LLVMConfig.cmake.in

@@ -140,8 +140,6 @@ set(LLVM_ENABLE_SHARED_LIBS @BUILD_SHARED_LIBS@)
 set(LLVM_DEFAULT_EXTERNAL_LIT "@LLVM_CONFIG_DEFAULT_EXTERNAL_LIT@")
 set(LLVM_LIT_ARGS "@LLVM_LIT_ARGS@")
 
-set(LLVM_HAVE_LIBXAR "@LLVM_HAVE_LIBXAR@")
-
 if(NOT TARGET LLVMSupport)
   @LLVM_CONFIG_INCLUDE_EXPORTS@
   @llvm_config_include_buildtree_only_exports@

llvm/include/llvm/Config/llvm-config.h.cmake

@@ -104,9 +104,6 @@
 /* Define to 1 if you have the <sysexits.h> header file. */
 #cmakedefine HAVE_SYSEXITS_H ${HAVE_SYSEXITS_H}
 
-/* Define if the xar_open() function is supported on this platform. */
-#cmakedefine LLVM_HAVE_LIBXAR ${LLVM_HAVE_LIBXAR}
-
 /* Define if building libLLVM shared library */
 #cmakedefine LLVM_BUILD_LLVM_DYLIB
 

llvm/test/CMakeLists.txt

@@ -1,6 +1,5 @@
 llvm_canonicalize_cmake_booleans(
   BUILD_SHARED_LIBS
-  LLVM_HAVE_LIBXAR
   HAVE_OCAMLOPT
   LLVM_ENABLE_DIA_SDK
   LLVM_ENABLE_FFI

llvm/test/lit.cfg.py

@@ -583,9 +583,6 @@ def have_ld64_plugin_support():
 ) and not re.match(r"^arm64(e)?-apple-(macos|darwin)", config.target_triple):
     config.available_features.add("debug_frame")
 
-if config.have_libxar:
-    config.available_features.add("xar")
-
 if config.enable_threads:
     config.available_features.add("thread_support")
 

llvm/test/lit.site.cfg.py.in

@@ -35,7 +35,6 @@ config.llvm_use_intel_jitevents = @LLVM_USE_INTEL_JITEVENTS@
 config.llvm_use_sanitizer = "@LLVM_USE_SANITIZER@"
 config.have_zlib = @LLVM_ENABLE_ZLIB@
 config.have_zstd = @LLVM_ENABLE_ZSTD@
-config.have_libxar = @LLVM_HAVE_LIBXAR@
 config.have_libxml2 = @LLVM_ENABLE_LIBXML2@
 config.have_curl = @LLVM_ENABLE_CURL@
 config.have_httplib = @LLVM_ENABLE_HTTPLIB@

llvm/tools/llvm-driver/CMakeLists.txt

@@ -27,11 +27,6 @@ set_target_properties(llvm-driver PROPERTIES OUTPUT_NAME llvm)
 target_link_libraries(llvm-driver PUBLIC ${LLVM_DRIVER_OBJLIBS})
 target_link_libraries(llvm-driver PUBLIC LLVMDebuginfod)
 
-if(LLVM_HAVE_LIBXAR)
-  # used by llvm-objdump
-  target_link_libraries(llvm-driver PUBLIC ${XAR_LIB})
-endif()
-
 if(APPLE)
   # dsymutil uses some CoreFoundation stuff on Darwin...
   target_link_libraries(llvm-driver PRIVATE "-framework CoreFoundation")

llvm/tools/llvm-objdump/CMakeLists.txt

@@ -42,10 +42,6 @@ if(NOT LLVM_TOOL_LLVM_DRIVER_BUILD)
   target_link_libraries(llvm-objdump PRIVATE LLVMDebuginfod)
 endif()
 
-if(LLVM_HAVE_LIBXAR AND NOT LLVM_TOOL_LLVM_DRIVER_BUILD)
-  target_link_libraries(llvm-objdump PRIVATE ${XAR_LIB})
-endif()
-
 add_llvm_tool_symlink(llvm-otool llvm-objdump)
 
 if(LLVM_INSTALL_BINUTILS_SYMLINKS)