[clang] [clang] add `-fimplicit-constexpr` flag (PR #136436)

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Hana =?utf-8?q?Dusíková?= <hanicka at hanicka.net>,
Hana =?utf-8?q?Dusíková?= <hanicka at hanicka.net>
Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/136436 at github.com>


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@@ -779,6 +779,9 @@ static void InitializeCPlusPlusFeatureTestMacros(const LangOptions &LangOpts,
 
   // TODO: Final number?
   Builder.defineMacro("__cpp_type_aware_allocators", "202500L");
+
+  if (LangOpts.ImplicitConstexpr) // same value as GCC
+    Builder.defineMacro("__cpp_implicit_constexpr", "20211111");
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cor3ntin wrote:

We don't usually define macros for non-standard feature. Instead users should use `__has_extension(cxx_implicit_constexpr)`

https://github.com/llvm/llvm-project/pull/136436