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

[Nhat Nguyen 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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changkhothuychung wrote:

I think I should rename this test file. The purpose when I created this test file is that reflection should not produce codegen, but since we don't implement consteval-only type yet, we will emit diagnostics for reflection in codegen and have `expected-error` in the test. 

Also, its related to [this discussion](https://github.com/llvm/llvm-project/pull/190356#discussion_r3033403682) at the moment.

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