[clang] [clang] Make __builtin_exp and __builtin_expf constexpr. (PR #199808)

[Hubert Tong via cfe-commits]

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@@ -0,0 +1,19 @@
+// RUN: %clang_cc1 -std=c++17 -fsyntax-only -verify %s
+// RUN: %clang_cc1 -std=c++17 -fsyntax-only -verify -fexperimental-new-constant-interpreter %s
+// expected-no-diagnostics
+
+constexpr float InfFloat = __builtin_inff();
+constexpr float NegInfFloat = -__builtin_inff();
+
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hubert-reinterpretcast wrote:

No testing with NaN input values?

https://github.com/llvm/llvm-project/pull/199808