[llvm][ubsan] Inclusive language: replace use of blacklist HandleLLVMOptions.cmake but use old option name

[ZarkoCA]

Summary

Retry at https://reviews.llvm.org/D113689, this time with using the old option name
to support older versions of clang.

[ZarkoCA]

Ping, I'd like to land this patch now that it uses the older option name if no one has any objections.

[bjope]

LGTM

llvm/cmake/modules/HandleLLVMOptions.cmake

if(LLVM_USE_SANITIZER)
   if (LLVM_USE_SANITIZER MATCHES "(Undefined;)?Address(;Undefined)?")
     add_flag_if_supported("-fsanitize-address-use-after-scope"
                           FSANITIZE_USE_AFTER_SCOPE_FLAG)
   endif()
   if (LLVM_USE_SANITIZE_COVERAGE)
     append("-fsanitize=fuzzer-no-link" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
   endif()
   if (LLVM_USE_SANITIZER MATCHES ".*Undefined.*")
-    set(BLACKLIST_FILE "${CMAKE_SOURCE_DIR}/utils/sanitizers/ubsan_blacklist.txt")
-    if (EXISTS "${BLACKLIST_FILE}")
-      append("-fsanitize-blacklist=${BLACKLIST_FILE}"
+    set(IGNORELIST_FILE "${CMAKE_SOURCE_DIR}/utils/sanitizers/ubsan_ignorelist.txt")
+    if (EXISTS "${IGNORELIST_FILE}")
+      # Use this option name version since -fsanitize-ignorelist is only
+      # accepted with clang 13.0 or newer.
+      append("-fsanitize-blacklist=${IGNORELIST_FILE}"
              CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
     endif()
   endif()
 endif()
 
 # Turn on -gsplit-dwarf if requested in debug builds.
 if (LLVM_USE_SPLIT_DWARF AND
     ((uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG") OR