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

[Louis Dionne via libcxx-commits]

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@@ -205,6 +205,7 @@ set(LIBCXX_ABI_NAMESPACE "__${LIBCXX_ABI_VERSION}" CACHE STRING "The inline ABI
 if (NOT LIBCXX_ABI_NAMESPACE MATCHES "__.*")
   message(FATAL_ERROR "LIBCXX_ABI_NAMESPACE must be a reserved identifier, got '${LIBCXX_ABI_NAMESPACE}'.")
 endif()
+set(LIBCXX_AVAILABILITY_MINIMUM_HEADER_VERSION "1" CACHE STRING "Minimum version of the libc++ headers that are used by binaries linked against the libc++ library")
----------------
ldionne wrote:

```suggestion
set(LIBCXX_AVAILABILITY_MINIMUM_HEADER_VERSION "1" CACHE STRING "Minimum version of the libc++ headers that are allowed to be used by binaries linked against the libc++ library. This version must correspond to a LLVM release major version.")
```

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