[clang] [Clang] Add constexpr eval for cmath builtins (PR #194327)

[Timm Baeder via cfe-commits]

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@@ -0,0 +1,187 @@
+// RUN: %clang_cc1 -fexperimental-new-constant-interpreter -verify -std=c++20 %s
+// RUN: %clang_cc1 -verify -std=c++20 %s
+
+// expected-no-diagnostics
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tbaederr wrote:

The round implementation issues a diagnostic but that doesn't seem to be tested.

https://github.com/llvm/llvm-project/pull/194327