[libcxx-commits] [libcxx] [libc++] Make bad_function_call::what() existence a matter of availability instead of ABI (PR #127697)

[Louis Dionne via libcxx-commits]

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@@ -51,12 +51,6 @@
 #  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
-// Override the default return value of exception::what() for bad_function_call::what()
-// with a string that is specific to bad_function_call (see http://wg21.link/LWG2233).
-// This is an ABI break on platforms that sign and authenticate vtable function pointers
-// because it changes the mangling of the virtual function located in the vtable, which
-// changes how it gets signed.
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ldionne wrote:

As we discussed in Hagenberg with Oliver Hunt, this information is actually untrue and I think we (I?) put it there by mistaking an issue I had seen with another kind of issue, likely related to ABI tags.

https://github.com/llvm/llvm-project/pull/127697