[clang] [Clang][Sema] Always use latest redeclaration of primary template (PR #114258)

[Krystian Stasiowski via cfe-commits]

sdkrystian wrote:

I should hopefully have a fix ready tomorrow... apologies for the delay @asmok-g! Getting this patch right is a bit hard since it touches all template instantiation related things :)

https://github.com/llvm/llvm-project/pull/114258