[libcxx-commits] [libcxx] [libc++] Document our ABI guarantees and what ABI flags exist to modify these guarantees (PR #132615)

[Mark de Wever via libcxx-commits]

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@@ -38,90 +38,47 @@
 #endif
 
 #if _LIBCPP_ABI_VERSION >= 2
-// Change short string representation so that string data starts at offset 0,
-// improving its alignment in some cases.
-#  define _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
-// Fix deque iterator type in order to support incomplete types.
-#  define _LIBCPP_ABI_INCOMPLETE_TYPES_IN_DEQUE
-// Fix undefined behavior in how std::list stores its linked nodes.
-#  define _LIBCPP_ABI_LIST_REMOVE_NODE_POINTER_UB
-// Fix undefined behavior in  how __tree stores its end and parent nodes.
-#  define _LIBCPP_ABI_TREE_REMOVE_NODE_POINTER_UB
-// Fix undefined behavior in how __hash_table stores its pointer types.
-#  define _LIBCPP_ABI_FIX_UNORDERED_NODE_POINTER_UB
-#  define _LIBCPP_ABI_FORWARD_LIST_REMOVE_NODE_POINTER_UB
-#  define _LIBCPP_ABI_FIX_UNORDERED_CONTAINER_SIZE_TYPE
+// TODO: Move the description of the remaining ABI flags to DesignDocs/ABIGuarantees.rst or remove them.
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mordante wrote:

Next to the TODO I like a normal comment describing where the information is available. This avoids loosing this information when the TODO is eventually removed.

https://github.com/llvm/llvm-project/pull/132615