[clang-tools-extra] [flang] [compiler-rt] [lld] [llvm] [libcxx] [clang] [lldb] [libc] [Clang][C++23] Implement P2448R2: Relaxing some constexpr restrictions (PR #77753)

[via cfe-commits]

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@@ -9108,7 +9123,8 @@ bool Sema::CheckExplicitlyDefaultedComparison(Scope *S, FunctionDecl *FD,
   //   declaration, it is implicitly considered to be constexpr.
   // FIXME: Only applying this to the first declaration seems problematic, as
   // simple reorderings can affect the meaning of the program.
-  if (First && !FD->isConstexpr() && Info.Constexpr)
+  if ((First && !FD->isConstexpr() && Info.Constexpr) ||
+      getLangOpts().CPlusPlus23)
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cor3ntin wrote:

isn't `Info.Constexpr` always true in c++ mode?
I'm trying to think of a meaningful test.

Haybe calling a comparison function of a class with a non-literal member from a consteval function?




https://github.com/llvm/llvm-project/pull/77753