[LLDB] Fix compilation with GCC 5

[mstorsjo]

@hans - this could be applied on 10.x (it seems to apply cleanly), to fix PR44791.

[hans]

In D74084#1861269, @mstorsjo wrote:

@hans - this could be applied on 10.x (it seems to apply cleanly), to fix PR44791.

Thanks! Cherry-picked as 22633f85bb7d317ff97c86b6ae7817b678777d93.

lldb/source/DataFormatters/FormatCache.cpp

 FormatCache::Entry &FormatCache::GetEntry(ConstString type) {
   auto i = m_map.find(type), e = m_map.end();
   if (i != e)
     return i->second;
   m_map[type] = FormatCache::Entry();
   return m_map[type];
 }
 
+namespace lldb_private {
+
 template<> bool FormatCache::Entry::IsCached<lldb::TypeFormatImplSP>() {
   return IsFormatCached();
 }
 template<> bool FormatCache::Entry::IsCached<lldb::TypeSummaryImplSP> () {
   return IsSummaryCached();
 }
 template<> bool FormatCache::Entry::IsCached<lldb::SyntheticChildrenSP>() {
   return IsSyntheticCached();
 }
 
+} // namespace lldb_private
+
 template <typename ImplSP>
 bool FormatCache::Get(ConstString type, ImplSP &format_impl_sp) {
   std::lock_guard<std::recursive_mutex> guard(m_mutex);
   auto entry = GetEntry(type);
   if (entry.IsCached<ImplSP>()) {
 #ifdef LLDB_CONFIGURATION_DEBUG
     m_cache_hits++;
 #endif

lldb/source/DataFormatters/LanguageCategory.cpp

bool result = m_category_sp->Get(valobj.GetObjectRuntimeLanguage(),
                                    match_data.GetMatchesVector(), retval_sp);
   if (match_data.GetTypeForCache() &&
       (!retval_sp || !retval_sp->NonCacheable())) {
     m_format_cache.Set(match_data.GetTypeForCache(), retval_sp);
   }
   return result;
 }
 
+namespace lldb_private {
+
 /// Explicit instantiations for the three types.
 /// \{
 template bool
 LanguageCategory::Get<lldb::TypeFormatImplSP>(FormattersMatchData &,
                                               lldb::TypeFormatImplSP &);
 template bool
 LanguageCategory::Get<lldb::TypeSummaryImplSP>(FormattersMatchData &,
                                                lldb::TypeSummaryImplSP &);
auto &LanguageCategory::GetHardcodedFinder<lldb::TypeSummaryImplSP>() {
   return m_hardcoded_summaries;
 }
 
 template <>
 auto &LanguageCategory::GetHardcodedFinder<lldb::SyntheticChildrenSP>() {
   return m_hardcoded_synthetics;
 }
 
+} // namespace lldb_private
+
 template <typename ImplSP>
 bool LanguageCategory::GetHardcoded(FormatManager &fmt_mgr,
                                     FormattersMatchData &match_data,
                                     ImplSP &retval_sp) {
   if (!IsEnabled())
     return false;
 
   ValueObject &valobj(match_data.GetValueObject());

lldb/source/Interpreter/CommandAlias.cpp

static bool ProcessAliasOptionsArgs(lldb::CommandObjectSP &cmd_obj_sp,
   }
 
   if (!options_string.empty()) {
     if (cmd_obj_sp->WantsRawCommandString())
       option_arg_vector->emplace_back("<argument>", -1, options_string);
     else {
       for (auto &entry : args.entries()) {
         if (!entry.ref().empty())
-          option_arg_vector->emplace_back("<argument>", -1, entry.ref());
+          option_arg_vector->emplace_back(std::string("<argument>"), -1,
+                                          std::string(entry.ref()));
       }
     }
   }
 
   return success;
 }
 
 CommandAlias::CommandAlias(CommandInterpreter &interpreter,

lldb/source/Interpreter/Options.cpp

           llvm::formatv("error with options table; invalid value in has_arg "
                         "field for option '{0}'.",
                         char(val))
               .str(),
           llvm::inconvertibleErrorCode());
     }
     if (!option_arg)
       option_arg = "<no-argument>";
-    option_arg_vector->emplace_back(option_str.GetString(), has_arg,
-                                    option_arg);
+    option_arg_vector->emplace_back(std::string(option_str.GetString()),
+                                    has_arg, std::string(option_arg));
 
     // Find option in the argument list; also see if it was supposed to take an
     // argument and if one was supplied.  Remove option (and argument, if
     // given) from the argument list.  Also remove them from the
     // raw_input_string, if one was passed in.
     size_t idx =
         FindArgumentIndexForOption(args_copy, long_options[long_options_index]);
     if (idx == size_t(-1))