ReleaseNotes: mention -mtls-dialect=desc

[MaskRay]

No description provided.

[llvmbot]

@llvm/pr-subscribers-clang

Author: Fangrui Song (MaskRay)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/82731.diff

1 Files Affected:

• (modified) clang/docs/ReleaseNotes.rst (+1)

diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 93a67e7a895592..6121ef7fa98c04 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -1286,6 +1286,7 @@ RISC-V Support
   for RV64.
 
 - ``__attribute__((rvv_vector_bits(N)))`` is now supported for RVV vbool*_t types.
+- ``-mtls-dialect=desc`` is now supported to enable TLS descriptors (TLSDESC).
 
 CUDA/HIP Language Changes
 ^^^^^^^^^^^^^^^^^^^^^^^^^