[clang] [Clang] [NFC] Add release note about libstdc++ bug (PR #93059)

[via cfe-commits]

https://github.com/Sirraide updated https://github.com/llvm/llvm-project/pull/93059

>From b7fde11f08a324b00e8179253dd327724b40cdc9 Mon Sep 17 00:00:00 2001
From: Sirraide <aeternalmail at gmail.com>
Date: Wed, 22 May 2024 17:49:11 +0200
Subject: [PATCH 1/2] [Clang] Add release note about libstdc++ bug

---
 clang/docs/ReleaseNotes.rst | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 5a123b0b86dda..58c73fb6947ce 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -59,6 +59,18 @@ C++ Specific Potentially Breaking Changes
 - Clang now performs semantic analysis for unary operators with dependent operands
   that are known to be of non-class non-enumeration type prior to instantiation.
 
+  This change uncovered a bug in libstdc++ 14.1.0 which may cause compile failures
+  on systems using that version of libstdc++ and Clang 19, with an error that looks
+  something like this:
+
+  .. code-block:: text
+
+    <source>:4:5: error: expression is not assignable
+    4 |     ++this;
+      |     ^ ~~~~
+
+  To fix this, update libstdc++ to a newer version, such as 14.1.1 or 14.2.
+
 ABI Changes in This Version
 ---------------------------
 - Fixed Microsoft name mangling of implicitly defined variables used for thread

>From 0de0483c4f54c4762d49368325fb9b72c8c599fb Mon Sep 17 00:00:00 2001
From: Sirraide <aeternalmail at gmail.com>
Date: Wed, 22 May 2024 18:01:20 +0200
Subject: [PATCH 2/2] Address review feedback

Co-authored-by: cor3ntin <corentinjabot at gmail.com>
---
 clang/docs/ReleaseNotes.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 58c73fb6947ce..8df98b8aad2d8 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -69,7 +69,7 @@ C++ Specific Potentially Breaking Changes
     4 |     ++this;
       |     ^ ~~~~
 
-  To fix this, update libstdc++ to a newer version, such as 14.1.1 or 14.2.
+  To fix this, update libstdc++ to version 14.1.1 or greater.
 
 ABI Changes in This Version
 ---------------------------