[clang] [Serialization] Fix lazy template loading (PR #133057)

[Maksim Ivanov via cfe-commits]

emaxx-google wrote:

> I had a closer look, but I get plenty of compile errors already on `main` - including
> 
> ```
> ./head15.h:20:7: error: use of overloaded operator '=' is ambiguous (with operand types 'std::vector<absl::string_view>' and 'strings_internal::Splitter<typename strings_internal::SelectDelimiter<char>::type, AllowEmpty, std::string>' (aka 'Splitter<char, strings_internal::AllowEmpty, basic_string>'))
> ```
> 
> I haven't even applied the change in this PR - what am I missing?

You're right - before sharing the reproducer I cross-checked that the error isn't produced by a slightly older version of Clang (a few weeks old), but I didn't check the most recent version. Apparently something changed in the last few weeks that affects this error regardless of your change. OK, I'm re-running the minimization now, this time with the interestingness test being "the given error is produced by compiler1 and not produced by compiler2=dd3addf954ac7e704fccc7d011217ba10461c883".

https://github.com/llvm/llvm-project/pull/133057