[clang] [C++23] [CLANG] Adding C++23 constexpr math functions: fmin and frexp. (PR #88978)

[Hubert Tong via cfe-commits]

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@@ -0,0 +1,38 @@
+// RUN: %clang_cc1 -DWIN -verify -std=c++23 -fsyntax-only  %s
+// RUN: %clang_cc1 -verify -std=c++23 -fsyntax-only  %s
+
+// expected-no-diagnostics
+
+
+#ifdef WIN
+#define INFINITY ((float)(1e+300 * 1e+300))
+#define NAN      (-(float)(INFINITY * 0.0F))
+#else
+#define NAN (__builtin_nanf(""))
+#define INFINITY (__builtin_inff())
+#endif
+
+int main() {
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hubert-reinterpretcast wrote:

Use identity instead of comparisons/classifications for validation:
```suggestion

template <auto, auto> constexpr bool is_same_val = false;
template <auto X> constexpr bool is_same_val<X, X> = true;

int main() {
```

https://github.com/llvm/llvm-project/pull/88978