[libcxx-commits] [libcxx] [libc++] Fix header deprecations (PR #163356)

[Louis Dionne via libcxx-commits]

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@@ -26,18 +26,10 @@
 #    pragma GCC system_header
 #  endif
 
-#  if _LIBCPP_STD_VER >= 20
-
-using __standard_header_ccomplex
-    _LIBCPP_DEPRECATED_("removed in C++20. Include <complex> instead.") _LIBCPP_NODEBUG = void;
-using __use_standard_header_ccomplex _LIBCPP_NODEBUG                                    = __standard_header_ccomplex;
-
-#  elif _LIBCPP_STD_VER >= 17
-
-using __standard_header_ccomplex _LIBCPP_DEPRECATED_("Include <complex> instead.") _LIBCPP_NODEBUG = void;
-using __use_standard_header_ccomplex _LIBCPP_NODEBUG = __standard_header_ccomplex;
-
+#  if _LIBCPP_STD_VER >= 17 && !__building_module(std) && _LIBCPP_DIAGNOSE_DEPRECATED_HEADERS
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ldionne wrote:

As you discussed just now, we could probably use a `#pragma clang deprecated_header("reason")`, that way this warning would be part of `-Wdeprecated` instead of `-W#warning`.

https://github.com/llvm/llvm-project/pull/163356