From ad0dfb4f5e07c337af45e1c4f515b762d2d1c395 Mon Sep 17 00:00:00 2001
From: Louis Dionne <ldionne.2@gmail.com>
Date: Mon, 19 Sep 2022 11:27:50 -0400
Subject: [PATCH] [libc++] Document the format of _LIBCPP_VERSION

Differential Revision: https://reviews.llvm.org/D134187
---
 libcxx/include/__config | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libcxx/include/__config b/libcxx/include/__config
index 681c10306420..b7ec57321780 100644
--- a/libcxx/include/__config
+++ b/libcxx/include/__config
@@ -24,6 +24,9 @@
 
 #ifdef __cplusplus
 
+// _LIBCPP_VERSION represents the version of libc++, which matches the version of LLVM.
+// Given a LLVM release LLVM XX.Y.ZZ (e.g. LLVM 16.0.1 == 16.0.01), _LIBCPP_VERSION is
+// defined to XXYZZ.
 #  define _LIBCPP_VERSION 16000
 
 #  define _LIBCPP_CONCAT_IMPL(_X, _Y) _X##_Y