diff --git a/libstdc++-v3/doc/doxygen/user.cfg.in b/libstdc++-v3/doc/doxygen/user.cfg.in
index fc82debd1b4..9393d5dfb43 100644
--- a/libstdc++-v3/doc/doxygen/user.cfg.in
+++ b/libstdc++-v3/doc/doxygen/user.cfg.in
@@ -2912,6 +2912,8 @@ PREDEFINED             = __cplusplus=202603L \
 			 _GLIBCXX_HAVE_ICONV=1 \
 			 "_GLIBCXX_DOXYGEN_ONLY(X)=X " \
 			 __exception_ptr=__unspecified__ \
+			 "_GLIBCXX_SIMD_BEGIN_NAMESPACE=namespace std::experimental::inline parallelism_v2 {" \
+			 "_GLIBCXX_SIMD_END_NAMESPACE=}" \
 
 
 # If the MACRO_EXPANSION and EXPAND_ONLY_PREDEF tags are set to YES then this
diff --git a/libstdc++-v3/include/experimental/bits/simd.h b/libstdc++-v3/include/experimental/bits/simd.h
index 8c30c8af268..ce0867fd8eb 100644
--- a/libstdc++-v3/include/experimental/bits/simd.h
+++ b/libstdc++-v3/include/experimental/bits/simd.h
@@ -55,6 +55,11 @@
 #include <arm_sve.h>
 #endif
 
+/** @namespace std::experimental::parallelism_v2
+ *  @ingroup ts_simd
+ */
+_GLIBCXX_SIMD_BEGIN_NAMESPACE
+
 /** @ingroup ts_simd
  * @{
  */
@@ -78,7 +83,6 @@
  * Variable names:
  * __k: mask object (vector- or bitmask)
  */
-_GLIBCXX_SIMD_BEGIN_NAMESPACE
 
 #if !_GLIBCXX_SIMD_X86INTRIN
 using __m128  [[__gnu__::__vector_size__(16)]] = float;