[clang] [clang][doc][SYCL] Add a very first SYCL release note (PR #200200)

[Mariya Podchishchaeva via cfe-commits]

https://github.com/Fznamznon created https://github.com/llvm/llvm-project/pull/200200

None

>From 28e82ca2673448f0ebc77fcb3689230fa2e13798 Mon Sep 17 00:00:00 2001
From: "Podchishchaeva, Mariya" <mariya.podchishchaeva at intel.com>
Date: Thu, 28 May 2026 07:59:22 -0700
Subject: [PATCH] [clang][doc][SYCL] Add a very first SYCL release note

---
 clang/docs/ReleaseNotes.rst | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 11cce36a0906c..80d1339d4e93c 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -942,6 +942,12 @@ OpenMP Support
 - Added support for ``local`` clause with declare_target directive when
   OpenMP >= 60.
 
+SYCL Support
+--------------
+- Clang now assumes default target for SYCL device compilation is 64-bit SPIR-V
+  and it now diagnoses if a non-supporting target is specified via command line.
+  (#GH167358)
+
 Improvements
 ^^^^^^^^^^^^
 - Improved substitution performance in concept checking. (#GH172266)