Index: clang/docs/ReleaseNotes.rst
===================================================================
--- clang/docs/ReleaseNotes.rst
+++ clang/docs/ReleaseNotes.rst
@@ -77,6 +77,9 @@
 - Implemented the ``unreachable`` macro in freestanding ``<stddef.h>`` for
   `WG14 N2826 <https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2826.pdf>`_
 
+- Removed the ``ATOMIC_VAR_INIT`` macro in C2x and later standards modes, which
+  implements `WG14 N2886 <https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2886.htm>`_
+
 Non-comprehensive list of changes in this release
 -------------------------------------------------
 - Clang now saves the address of ABI-indirect function parameters on the stack,
Index: clang/lib/Headers/stdatomic.h
===================================================================
--- clang/lib/Headers/stdatomic.h
+++ clang/lib/Headers/stdatomic.h
@@ -45,9 +45,16 @@
 #define ATOMIC_POINTER_LOCK_FREE    __CLANG_ATOMIC_POINTER_LOCK_FREE
 
 /* 7.17.2 Initialization */
-
+/* FIXME: This is using the placeholder dates Clang produces for these macros
+   in C2x mode; switch to the correct values once they've been published. */
+#if (defined(__STDC_VERSION__) && __STDC_VERSION__ < 202000L) ||               \
+    defined(__cplusplus)
+/* ATOMIC_VAR_INIT was removed in C2x, but still remains in C++2b. */
 #define ATOMIC_VAR_INIT(value) (value)
-#if ((defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201710L) ||             \
+#endif
+
+#if ((defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201710L &&              \
+      __STDC_VERSION__ < 202000L) ||                                           \
      (defined(__cplusplus) && __cplusplus >= 202002L)) &&                      \
     !defined(_CLANG_DISABLE_CRT_DEPRECATION_WARNINGS)
 /* ATOMIC_VAR_INIT was deprecated in C17 and C++20. */
Index: clang/test/C/C2x/n2886.c
===================================================================
--- /dev/null
+++ clang/test/C/C2x/n2886.c
@@ -0,0 +1,20 @@
+// RUN: %clang_cc1 -verify=okay -std=c11 -ffreestanding %s
+// RUN: %clang_cc1 -verify -std=c17 -ffreestanding %s
+// RUN: %clang_cc1 -verify -std=c2x -ffreestanding %s
+
+/* WG14 N2886: yes
+ * Remove ATOMIC_VAR_INIT v2
+ */
+
+/* okay-no-diagnostics */
+#include <stdatomic.h>
+
+_Atomic int a = ATOMIC_VAR_INIT(0); /* #diag */
+#if __STDC_VERSION__ <= 201710L
+/* expected-warning@#diag {{macro 'ATOMIC_VAR_INIT' has been marked as deprecated}}
+   expected-note@stdatomic.h:* {{macro marked 'deprecated' here}}
+*/
+#else
+/* expected-error@#diag {{use of undeclared identifier 'ATOMIC_VAR_INIT'}} */
+#endif
+
Index: clang/www/c_status.html
===================================================================
--- clang/www/c_status.html
+++ clang/www/c_status.html
@@ -1131,7 +1131,7 @@
     <tr>
       <td>Remove ATOMIC_VAR_INIT v2</td>
       <td><a href="https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2886.htm">N2886</a></td>
-      <td class="none" align="center">No</td>
+      <td class="unreleased" align="center">Clang 17</td>
     </tr>
     <tr>
       <td>Require exact-width integer type interfaces v2</td>