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

[via cfe-commits]

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@@ -57,6 +57,12 @@ template <> struct Bounds<double> {
 } // namespace exp_internal
 
 template <typename T> LIBC_INLINE int exp_exceptions(T x, int rounding_mode) {
+  static_assert(FE_OVERFLOW != 0);
+  static_assert(FE_UNDERFLOW != 0);
+  static_assert(FE_INEXACT != 0);
+  static_assert(FE_INVALID != 0);
+  static_assert(FE_DIVBYZERO != 0);
+
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lntue wrote:

Turn out the problem was the incorrect LLVM_READONLY attribute I added to APFloat::exp previously.

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