[clang] [Clang] Fix conversion from floats to bool-backed enums per CWG1094 (PR #211172)

[Vlad Serebrennikov via cfe-commits]

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@@ -111,3 +119,34 @@ namespace cwg1070 { // cwg1070: 3.5
   C c = {};
 #endif
 } // namespace cwg1070
+
+#if __cplusplus >= 201103L
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Endilll wrote:

Put `#if`/`#endif` pair within the cwg1904 namespace

https://github.com/llvm/llvm-project/pull/211172