[tools] Fix buildbot build failure

/buildbot/worker/arc-folder/llvm-project/clang/tools/c-index-test/c-index-test.c:234: warning: ignoring '#pragma clang diagnostic' [-Wunknown-pragmas]
/buildbot/worker/arc-folder/llvm-project/clang/tools/c-index-test/c-index-test.c:235: warning: ignoring '#pragma clang diagnostic' [-Wunknown-pragmas]
/buildbot/worker/arc-folder/llvm-project/clang/tools/c-index-test/c-index-test.c:236:10: warning: cast discards 'const' qualifier from pointer target type [-Wcast-qual]
/buildbot/worker/arc-folder/llvm-project/clang/tools/c-index-test/c-index-test.c:237:10: warning: cast discards 'const' qualifier from pointer target type [-Wcast-qual]
/buildbot/worker/arc-folder/llvm-project/clang/tools/c-index-test/c-index-test.c:238: warning: ignoring '#pragma clang diagnostic' [-Wunknown-pragmas]
/buildbot/worker/arc-folder/llvm-project/clang/tools/c-index-test/c-index-test.c:3765: warning: ignoring '#pragma clang diagnostic' [-Wunknown-pragmas]
/buildbot/worker/arc-folder/llvm-project/clang/tools/c-index-test/c-index-test.c:3766: warning: ignoring '#pragma clang diagnostic' [-Wunknown-pragmas]
/buildbot/worker/arc-folder/llvm-project/clang/tools/c-index-test/c-index-test.c:3767:10: warning: cast discards 'const' qualifier from pointer target type [-Wcast-qual]
/buildbot/worker/arc-folder/llvm-project/clang/tools/c-index-test/c-index-test.c:3768: warning: ignoring '#pragma clang diagnostic' [-Wunknown-pragmas]

Author: DamonFool

clang/tools/c-index-test/c-index-test.c

@@ -231,11 +231,15 @@ void free_remapped_files(struct CXUnsavedFile *unsaved_files,
                          int num_unsaved_files) {
   int i;
   for (i = 0; i != num_unsaved_files; ++i) {
+#if defined(__clang__)
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wcast-qual"
+#endif
     free((char *)unsaved_files[i].Filename);
     free((char *)unsaved_files[i].Contents);
+#if defined(__clang__)
 #pragma clang diagnostic pop
+#endif
   }
   free(unsaved_files);
 }
@@ -3762,10 +3766,14 @@ index_startedTranslationUnit(CXClientData client_data, void *reserved) {
   printCheck(index_data);
 
   printf("[startedTranslationUnit]\n");
+#if defined(__clang__)
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wcast-qual"
+#endif
   return (CXIdxClientContainer)"TU";
+#if defined(__clang__)
 #pragma clang diagnostic pop
+#endif
 }
 
 static void index_indexDeclaration(CXClientData client_data,