[docs] Add release notes for news in 16.x done by me, or otherwise relating to MinGW targets

[mstorsjo]

Summary

These are cases where we've missed to add release notes when the features
were developed.

Posting this mostly as a headsup if people want to comment - I intend on
landing this before the branch is created tomorrow in any case.

[aaron.ballman]

Clang bits LGTM (so do the rest FWIW).

[alvinhochun]

Thanks, LGTM for the parts I touched and also the rest of the stuff (but I didn't proofread carefully).

[MaskRay]

lld/docs/ReleaseNotes.rst

78

s/dpes/does/

[mstorsjo]

lld/docs/ReleaseNotes.rst

78

Thanks! I'll fix this before landing it.

clang/docs/ReleaseNotes.rst

 - ``-fmodules-ts`` has been deprecated. The flag will be removed in Clang 17.
   Please use ``-std=c++20`` or higher to use standard C++ modules instead.
 
 Modified Compiler Flags
 -----------------------
 - Clang now permits specifying ``--config=`` multiple times, to load multiple
   configuration files.
 
+- The option ``-rtlib=platform`` can now be used for all targets to override
+  a different option value (either one set earlier on the command line, or a
+  built-in hardcoded default). (Previously the MSVC and Darwin targets didn't
+  allow this parameter combination.)
+
 Removed Compiler Flags
 -------------------------
 - Clang now no longer supports ``-cc1 -fconcepts-ts``.  This flag has been deprecated
   and encouraged use of ``-std=c++20`` since Clang 10, so we're now removing it.
 
 New Pragmas in Clang
 --------------------
 - ...

 ---------------
 - For the MinGW driver, added the options ``-mguard=none``, ``-mguard=cf`` and
   ``-mguard=cf-nochecks`` (equivalent to ``/guard:cf-``, ``/guard:cf`` and
   ``/guard:cf,nochecks`` in clang-cl) for enabling Control Flow Guard checks
   and generation of address-taken function table.
 
 - Switched from SHA1 to BLAKE3 for PDB type hashing / ``-gcodeview-ghash``
 
+- Fixed code generation with emulated TLS, when the emulated TLS is enabled
+  by default (with downstream patches; no upstream configurations default
+  to this configuration, but some mingw downstreams change the default
+  in this way).
+
+- Improved detection of MinGW cross sysroots for finding sysroots provided
+  by Linux distributions such as Fedora. Also improved such setups by
+  avoiding to include ``/usr/include`` among the include paths when cross
+  compiling with a cross sysroot based in ``/usr``.
+
 AIX Support
 -----------
 * When using ``-shared``, the clang driver now invokes llvm-nm to create an
   export list if the user doesn't specify one via linker flag or pass an
   alternative export control option.
 
 C Language Changes in Clang
 ---------------------------

lld/docs/ReleaseNotes.rst

 * The linker command line entry in ``S_ENVBLOCK`` of the PDB is now stripped
   from input files, to align with MSVC behavior.
   (`D137723 <https://reviews.llvm.org/D137723>`_)
 * Switched from SHA1 to BLAKE3 for PDB type hashing / ``-gcodeview-ghash``
   (`D137101 <https://reviews.llvm.org/D137101>`_)
 * Improvements to the PCH.OBJ files handling. Now LLD behaves the same as MSVC
   link.exe when merging PCH.OBJ files that don't have the same signature.
   (`D136762 <https://reviews.llvm.org/D136762>`_)
+* Changed the OrdinalBase for DLLs from 0 to 1, matching the output from
+  both MS link.exe and GNU ld. (`D134140 <https://reviews.llvm.org/D134140>`_)
 
 MinGW Improvements
 ------------------
 
 * The lld-specific options ``--guard-cf``, ``--no-guard-cf``,
   ``--guard-longjmp`` and ``--no-guard-longjmp`` has been added to allow
   enabling Control Flow Guard and long jump hardening. These options are
   disabled by default, but enabling ``--guard-cf`` will also enable
   ``--guard-longjmp`` unless ``--no-guard-longjmp`` is also specified.
   ``--guard-longjmp`` depends on ``--guard-cf`` and cannot be used by itself.
   Note that these features require the ``_load_config_used`` symbol to contain
   the load config directory and be filled with the required symbols.
   (`D132808 <https://reviews.llvm.org/D132808>`_)
 
+* Pick up libraries named ``<name>.lib`` when linked with ``-l<name>``, even
+  if ``-static`` has been specified. This fixes conformance to what
+  GNU ld dpes. (`D135651 <https://reviews.llvm.org/D135651>`_)
+
+* Unwinding in Rust code on i386 in MinGW builds has been fixed, by avoiding
+  to leave out the ``rust_eh_personality`` symbol.
+  (`D136879 <https://reviews.llvm.org/D136879>`_)
+
 MachO Improvements
 ------------------
 
 WebAssembly Improvements
 ------------------------
 

llvm/docs/ReleaseNotes.rst

 * When using multi-threaded LLVM tools (such as LLD) on a Windows host with a
   large number of processors or CPU sockets, previously the LLVM ThreadPool
   would span out threads to use all processors.
   Starting with Windows Server 2022 and Windows 11, the behavior has changed,
   the OS now spans out threads automatically to all processors. This also fixes
   an affinity mask issue.
   (`D138747 <https://reviews.llvm.org/D138747>`_)
 
+* When building LLVM and related tools for Windows with Clang in MinGW mode,
+  hidden symbol visiblity is now used to reduce the number of exports in
+  builds with dylibs (``LLVM_BUILD_LLVM_DYLIB`` or ``LLVM_LINK_LLVM_DYLIB``),
+  making such builds more manageable without running into the limit of
+  number of exported symbols.
+
+* AArch64 SEH unwind info generation bugs have been fixed; there were minor
+  cases of mismatches between the generated unwind info and actual
+  prologues/epilogues earlier in some cases.
+
+* AArch64 SEH unwind info is now generated correctly for the AArch64
+  security features BTI (Branch Target Identification) and PAC (Pointer
+  Authentication Code). In particular, using PAC with older versions of LLVM
+  would generate code that would fail to unwind at runtime, if the host
+  actually would use the pointer authentication feature.
+
+* Fixed stack alignment on Windows on AArch64, for stack frames with a
+  large enough allocation that requires stack probing.
+
 Changes to the X86 Backend
 --------------------------
 
 * Add support for the ``RDMSRLIST and WRMSRLIST`` instructions.
 * Add support for the ``WRMSRNS`` instruction.
 * Support ISA of ``AMX-FP16`` which contains ``tdpfp16ps`` instruction.
 * Support ISA of ``CMPCCXADD``.
 * Support ISA of ``AVX-IFMA``.
* ``llvm-readobj --elf-output-style=JSON`` no longer prefixes each JSON object
   ``{"FileSummary":{"File":"main.o"},...}``. This allows each JSON object to be
   parsed in the same way, since each object no longer has a unique key. Tools
   that consume ``llvm-readobj``'s JSON output should update their parsers
   accordingly.
 
 * ``llvm-objdump`` now uses ``--print-imm-hex`` by default, which brings its
   default behavior closer in line with ``objdump``.
 
+* ``llvm-objcopy`` no longer writes corrupt addresses to empty sections if
+  the input file had a nonzero address to an empty section.
+
 Changes to LLDB
 ---------------------------------
 
 * Initial support for debugging Linux LoongArch 64-bit binaries.
 
+* Improvements in COFF symbol handling; previously a DLL (without any other
+  debug info) would only use the DLL's exported symbols, while it now also
+  uses the full list of internal symbols, if available.
+
+* Avoiding duplicate DLLs in the runtime list of loaded modules on Windows.
+
 Changes to Sanitizers
 ---------------------
 
 * Many Sanitizers (asan, fuzzer, lsan, safestack, scudo, tsan, ubsan) have
   support for Linux LoongArch 64-bit variant. Some of them may be rudimentary.
 
 Other Changes
 -------------
 
 * lit no longer supports using substrings of the default target triple as
   feature names in ``UNSUPPORTED:`` and ``XFAIL:`` directives. These have been
   replaced by the ``target=<triple>`` feature, and tests can use regex
   matching to achieve the same effect. For example, ``UNSUPPORTED: arm``
   would now be ``UNSUPPORTED: target=arm{{.*}}`` and ``XFAIL: windows``
   would now be ``XFAIL: target={{.*}}-windows{{.*}}``.
 
+* When cross compiling LLVM (or building with ``LLVM_OPTIMIZED_TABLEGEN``),
+  it is now possible to point the build to prebuilt versions of all the
+  host tools with one CMake variable, ``LLVM_NATIVE_TOOL_DIR``, instead of
+  having to point out each individual tool with variables such as
+  ``LLVM_TABLEGEN``, ``CLANG_TABLEGEN``, ``LLDB_TABLEGEN`` etc.
+
 External Open Source Projects Using LLVM 15
 ===========================================
 
 * A project...
 
 Additional Information
 ======================
 

openmp/docs/ReleaseNotes.rst

 
 This document contains the release notes for the OpenMP runtime, release 16.0.0.
 Here we describe the status of OpenMP, including major improvements
 from the previous release. All OpenMP releases may be downloaded
 from the `LLVM releases web site <https://llvm.org/releases/>`_.
 
 Non-comprehensive list of changes in this release
 =================================================
+
+* Support for building the OpenMP runtime for Windows on AArch64 and ARM
+  with MinGW based toolchains.
+
+* Made the OpenMP runtime tests run successfully on Windows.