Remove third party stuff and use gtest patch

D138472.diff

@@ -0,0 +1,53 @@
+From 04ee57212326f872b6f9402eff438220396ca763 Mon Sep 17 00:00:00 2001
+From: Konrad Kleine <kkleine@redhat.com>
+Date: Mon, 23 Jan 2023 13:14:17 +0000
+Subject: [PATCH] Rebased D138472
+
+---
+ clang/CMakeLists.txt | 23 ++++++++++-------------
+ 1 file changed, 10 insertions(+), 13 deletions(-)
+
+diff --git a/clang/CMakeLists.txt b/clang/CMakeLists.txt
+index 090cfa352078..69652733e2f2 100644
+--- a/clang/CMakeLists.txt
++++ b/clang/CMakeLists.txt
+@@ -118,12 +118,11 @@ if(CLANG_BUILT_STANDALONE)
+         set(LLVM_UTILS_PROVIDED ON)
+         set(CLANG_TEST_DEPS FileCheck count not)
+       endif()
+-      set(UNITTEST_DIR ${LLVM_THIRD_PARTY_DIR}/unittest)
+-      if(EXISTS ${UNITTEST_DIR}/googletest/include/gtest/gtest.h
+-          AND NOT EXISTS ${LLVM_LIBRARY_DIR}/${CMAKE_STATIC_LIBRARY_PREFIX}gtest${CMAKE_STATIC_LIBRARY_SUFFIX}
+-          AND EXISTS ${UNITTEST_DIR}/CMakeLists.txt)
+-        add_subdirectory(${UNITTEST_DIR} third-party/unittest)
+-      endif()
++    endif()
++
++    find_package(LLVMGTest)
++    if (NOT TARGET llvm_gtest)
++        message(FATAL_ERROR "llvm-gtest not found. Please install llvm-gtest or disable tests with -DLLVM_INCLUDE_TESTS=OFF")
+     endif()
+ 
+     if(LLVM_LIT)
+@@ -506,13 +505,11 @@ endif()
+ 
+ 
+ if( CLANG_INCLUDE_TESTS )
+-  if(EXISTS ${LLVM_THIRD_PARTY_DIR}/unittest/googletest/include/gtest/gtest.h)
+-    add_subdirectory(unittests)
+-    list(APPEND CLANG_TEST_DEPS ClangUnitTests)
+-    list(APPEND CLANG_TEST_PARAMS
+-      clang_unit_site_config=${CMAKE_CURRENT_BINARY_DIR}/test/Unit/lit.site.cfg
+-      )
+-  endif()
++  add_subdirectory(unittests)
++  list(APPEND CLANG_TEST_DEPS ClangUnitTests)
++  list(APPEND CLANG_TEST_PARAMS
++    clang_unit_site_config=${CMAKE_CURRENT_BINARY_DIR}/test/Unit/lit.site.cfg
++  )
+   add_subdirectory(test)
+   add_subdirectory(bindings/python/tests)
+ 
+-- 
+2.34.3
+

clang.spec

@@ -67,6 +67,9 @@ Patch6:     0001-Take-into-account-Fedora-Specific-install-dir-for-li.patch
 # Make clangBasic and clangDriver depend on LLVMTargetParser
 # See https://reviews.llvm.org/D141581
 Patch7:     D141581.diff
+# clang/cmake: Use installed gtest libraries for stand-alone builds
+# See https://reviews.llvm.org/D138472
+Patch8:     D138472.diff
 
 %if %{without compat_build}
 # Patches for clang-tools-extra