[clang] [clang]: support std::meta::info for primitive types (PR #190356)

[via cfe-commits]

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@@ -1,6 +1,10 @@
 // RUN: %clang_cc1 -std=c++26 -freflection -triple x86_64-unknown-linux-gnu \
 // RUN:   -emit-llvm -o - %s -verify
 
+constexpr auto r = ^^int;
+constexpr auto q = r;
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Sirraide wrote:

If we _just_ want to test the mangling, we should (eventually) use an NTTP of type `meta::info` for that; does that already work with this pr?

https://github.com/llvm/llvm-project/pull/190356