Matheus Izvekov 7284e0f3a4 [clang] mangle placeholder for deduced type as a template-prefix (#106335) ...

As agreed on https://github.com/itanium-cxx-abi/cxx-abi/issues/109 these
placeholders should be mangled as a `template-prefix` production.

```
    <template-prefix> ::= <template unqualified-name>           # global template
                      ::= <prefix> <template unqualified-name>  # nested template
                      ::= <template-param>                      # template template parameter
                      ::= <substitution>
```

Previous to this patch, the template template parameter case was not
handled, and template template parameters were incorrectly being handled
as unqualified-names.

Before #95202, DeducedTemplateType was not canonicalized correctly, so
that template template parameter declarations were retained
uncanonicalized.

After #95202, they are correctly canonicalized, but this now leads to
these TTPs being anonymous entities, where the mangling implementation
correctly doesn't expect an anonymous declaration of this kind, leading
to a crash.

Fixes #106182.

2024-08-29 18:53:03 -03:00

321 B

Raw Blame History

View Raw