[PATCH] D54048: [AST] Get aliased type info from an aliased TemplateSpecialization.

[John McCall via Phabricator via cfe-commits]

rjmccall added a comment.

Changing how `TemplateSpecializationType` is declared in `TypeNodes.def` has way more implications than you're giving it credit for.

`FooType::desugar()` should always perform a single-step desugar, but on `TemplateSpecializationType` it's calling `getCanonicalTypeInternal()`, which is clearly not a single-step desugar for a template alias.  So I believe the fix here is as simple as just returning `getAliasedType()` from that method for template aliases.


https://reviews.llvm.org/D54048