[docs] Add release notes for notable things I've contributed since last release

[mstorsjo]

docs/ReleaseNotes.rst

190 ↗

(On Diff #182754)

This comment doesn't really say much for the casual reader, perhaps it should just be left out and regarded as general assorted bugfixes? Although the fix (D55698) is a notable step towards matching GCC better for MinGW, and fixes an actual issue (building Qt in debug mode).

[hans]

docs/ReleaseNotes.rst

190 ↗

(On Diff #182754)

I think keeping it in is fine. If you want you could of course expand with mentioning the Qt part of your comment and maybe link to a bug entry if applicable.

[rnk]

docs/ReleaseNotes.rst

190 ↗

(On Diff #182754)

I agree, I think the info about Qt is the kind of newsworthy thing users will want to know and will understand.

cfe/branches/release_80/docs/ReleaseNotes.rst

 ------------------
 
 - ``-fprofile-filter-files=[regexes]`` and ``-fprofile-exclude-files=[regexes]``.
 
   Clang has now options to filter or exclude some files when
   instrumenting for gcov-based profiling.
   See the :doc:`UsersManual` for details.
 
+- When using a custom stack alignment, the ``stackrealign`` attribute is now
+  implicitly set on the main function.
+
 - ...
 
 Deprecated Compiler Flags
 -------------------------
 
 The following options are deprecated and ignored. They will be removed in
 future versions of Clang.
 
- clang-cl now supports the use of the precompiled header options /Yc and /Yu
   filename, a `#pragma hdrstop` inside the source marks the end of the
   precompiled code.
 
 - clang-cl has a new command-line option, ``/Zc:dllexportInlines-``, similar to
   ``-fvisibility-inlines-hidden`` on non-Windows, that makes class-level
   `dllexport` and `dllimport` attributes not apply to inline member functions.
   This can significantly reduce compile and link times. See the `User's Manual
   <UsersManual.html#the-zc-dllexportinlines-option>`_ for more info.
+
+- For MinGW, ``-municode`` now correctly defines ``UNICODE`` during
+  preprocessing.
+
+- For MinGW, clang now produces vtables and RTTI for dllexported classes
+  without key functions. This fixes building Qt in debug mode.
+
+- Allow using Address Sanitizer and Undefined Behaviour Sanitizer on MinGW.
+
 - ...
 
 
 C Language Changes in Clang
 ---------------------------
 
 - ...