Index: llvm/cmake/modules/HandleLLVMOptions.cmake
===================================================================
--- llvm/cmake/modules/HandleLLVMOptions.cmake
+++ llvm/cmake/modules/HandleLLVMOptions.cmake
@@ -1019,14 +1019,14 @@
 set(LLVM_SOURCE_PREFIX "" CACHE STRING "Use prefix for sources in debug info")
 
 if(LLVM_USE_RELATIVE_PATHS_IN_DEBUG_INFO)
-  check_c_compiler_flag("-fdebug-prefix-map=foo=bar" SUPPORTS_FDEBUG_PREFIX_MAP)
+  check_c_compiler_flag("-ffile-prefix-map=foo=bar" SUPPORTS_FFILE_PREFIX_MAP)
   if(LLVM_ENABLE_PROJECTS_USED)
     get_filename_component(source_root "${LLVM_MAIN_SRC_DIR}/.." ABSOLUTE)
   else()
     set(source_root "${LLVM_MAIN_SRC_DIR}")
   endif()
   file(RELATIVE_PATH relative_root "${source_root}" "${CMAKE_BINARY_DIR}")
-  append_if(SUPPORTS_FDEBUG_PREFIX_MAP "-fdebug-prefix-map=${CMAKE_BINARY_DIR}=${relative_root}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
-  append_if(SUPPORTS_FDEBUG_PREFIX_MAP "-fdebug-prefix-map=${source_root}/=${LLVM_SOURCE_PREFIX}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
+  append_if(SUPPORTS_FFILE_PREFIX_MAP "-ffile-prefix-map=${CMAKE_BINARY_DIR}=${relative_root}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
+  append_if(SUPPORTS_FFILE_PREFIX_MAP "-ffile-prefix-map=${source_root}/=${LLVM_SOURCE_PREFIX}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
   add_flag_if_supported("-no-canonical-prefixes" NO_CANONICAL_PREFIXES)
 endif()