[libcxx-commits] [libcxx] [libc++] Introduce the notion of a minimum header version (PR #166074)

[Louis Dionne via libcxx-commits]

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@@ -547,14 +547,10 @@ typedef __char32_t char32_t;
 #  endif
 #  define _LIBCPP_HIDE_FROM_ABI_VIRTUAL _LIBCPP_HIDDEN _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION
 
-#  ifdef _LIBCPP_BUILDING_LIBRARY
-#    if _LIBCPP_ABI_VERSION > 1
-#      define _LIBCPP_HIDE_FROM_ABI_AFTER_V1 _LIBCPP_HIDE_FROM_ABI
-#    else
-#      define _LIBCPP_HIDE_FROM_ABI_AFTER_V1
-#    endif
+#  if defined(_LIBCPP_BUILDING_LIBRARY) && _LIBCPP_AVAILABILITY_MINIMUM_HEADER_VERSION < 8
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ldionne wrote:

I think this shouldn't live in `__config`. This should probably be in either `availability.h` or in some other header like `dylib_availability.h` or `reverse_availability.h` where we encode things that pertain only to the dylib build.

https://github.com/llvm/llvm-project/pull/166074