commit 1c48c9cc43dbbbd1751e15d199b4d7d4fc52d828
author Louis Dionne <ldionne.2@gmail.com> Mon Aug 26 09:58:19 2024 -0400
committer GitHub <noreply@github.com> Mon Aug 26 09:58:19 2024 -0400
tree 5313441be67435b2712f552668be2efc8a0f6f0b
parent ca95bee649724a6092989076322daa501a0a6594

[libc++] Implement P2985R0: std::is_virtual_base_of (#105847)

This trait is implemented in C++26 conditionally on the compiler
supporting the __builtin_is_virtual_base_of intrinsic. I believe only
tip-of-trunk Clang currently implements that builtin.

Closes #105432

libcxx/docs/FeatureTestMacroTable.rst

diff --git a/libcxx/docs/FeatureTestMacroTable.rst b/libcxx/docs/FeatureTestMacroTable.rst
index a1506e1..f6d3142 100644
--- a/libcxx/docs/FeatureTestMacroTable.rst
+++ b/libcxx/docs/FeatureTestMacroTable.rst
@@ -442,7 +442,7 @@
     ---------------------------------------------------------- -----------------
     ``__cpp_lib_inplace_vector``                               *unimplemented*
     ---------------------------------------------------------- -----------------
-    ``__cpp_lib_is_virtual_base_of``                           *unimplemented*
+    ``__cpp_lib_is_virtual_base_of``                           ``202406L``
     ---------------------------------------------------------- -----------------
     ``__cpp_lib_is_within_lifetime``                           *unimplemented*
     ---------------------------------------------------------- -----------------