[clang] [clang] Add noipa attribute (PR #207502)

[Mariya Podchishchaeva via cfe-commits]

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@@ -0,0 +1,7 @@
+// RUN: %clang_cc1 -verify -fsyntax-only %s
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Fznamznon wrote:

Can the attribute be applied to member functions and/or function templates? Does it make sense to test constexpr functions?
Also, I think C and C++ Sema tests can be merged as well. C++ specific features can be guarded by macros.

https://github.com/llvm/llvm-project/pull/207502