[Lldb-commits] [clang] [clang-tools-extra] [lldb] [clang] Reland: Instantiate alias templates with sugar (PR #101858)

[Matheus Izvekov via lldb-commits]

mizvekov wrote:

The basic premise here was implemented back in D134604, and this has been  for a few years applied in some cases, like substitution of default arguments.

We leave a Subst* node behind with the purpose of somewhere down the line changing it back to what the user wrote.

So we don't leave a Subst* node behind when we don't need to resugar, or in the future when we implement clang's own resugarer, we wouldn't leave it behind after resugaring as well.

This reduces the cost of this sugared substitution and resugaring, and would help achieving the goal of merging our own resugarer in the future.

>From past conversations with IWYU maintainer, this was desirable, since IWYU rolls its own resugarer, which is faulty and difficult to maintain.

Now this other use case was never put forward before, and it looks like there might be some alternative way of doing this.



https://github.com/llvm/llvm-project/pull/101858