sdkrystian wrote: I don't think this is the right approach. I stepped though the example and the reason we reject is because: - We substitute a dependent `AutoType` in for the types of the template parameters when they are initially built. - We call `getMoreSpecialized` determine whether the partial specialization is more specialized than the primary. - We determine that neither template is at least as specialized as the other via `isAtLeastAsSpecializedAs`. - We call `TemplateParameterListsAreEqual` per [[temp.func.order] p6.2.2](http://eel.is/c++draft/temp.func.order#6.2.2) to check for template parameter equivalence, and compare the two template parameters by calling `MatchTemplateParameterKind`. - `MatchTemplateParameterKind` calls `ASTContext::getUnconstrainedType` to get the unconstrained type of the template parameters per [[temp.over.link] p6 sentence 2](http://eel.is/c++draft/temp.over.link#6.sentence-2). For class templates template parameter, it returns the type unchanged (a ***dependent*** `AutoType`). For the class template partial specializations template parameter, it returns an unconstrained `AutoType` ***that isn't dependent***. - We compare the adjusted types and determine they aren't equal, so we consider neither template to be more specialized than the other.
So, I think the correct fix is to propagate dependence in `ASTContext::getUnconstrainedType`. I have a branch that implements this [here](https://github.com/sdkrystian/llvm-project/tree/partial-spec-dependent-auto). WDYT @erichkeane @cor3ntin? https://github.com/llvm/llvm-project/pull/91842 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
