[clang] 482fad4 - [clang][DOC] Document module mangler changes

[Nathan Sidwell via cfe-commits]

Author: Nathan Sidwell
Date: 2022-04-06T11:13:32-07:00
New Revision: 482fad4a3fcb013aa19e97661e3d66583d026bb8

URL: https://github.com/llvm/llvm-project/commit/482fad4a3fcb013aa19e97661e3d66583d026bb8
DIFF: https://github.com/llvm/llvm-project/commit/482fad4a3fcb013aa19e97661e3d66583d026bb8.diff

LOG: [clang][DOC] Document module mangler changes

Note that the mangling has changed and the demangler's learnt a new
trick.  Obviously dependent upon the mangler and demangler patches.

Reviewed By: bruno

Differential Revision: https://reviews.llvm.org/D123141

Added: 
    

Modified: 
    clang/docs/ReleaseNotes.rst

Removed: 
    


################################################################################
diff  --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index bf592329ac02a..df6a7d7539ee6 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -201,6 +201,13 @@ C++20 Feature Support
 
 - Implemented `__builtin_source_location()` which enables library support for std::source_location.
 
+- The mangling scheme for C++20 modules has incompatibly changed. The
+  initial mangling was discovered not to be reversible, and the weak
+  ownership design decision did not give the backwards compatibility
+  that was hoped for. C++20 since added ``extern "C++"`` semantics
+  that can be used for such compatibility. The demangler now demangles
+  symbols with named module attachment.
+
 C++2b Feature Support
 ^^^^^^^^^^^^^^^^^^^^^