[clang] [Headers][X86] Ensure the CONSTEXPR attributes are undefined at the end of the vpopcntdq headers (PR #152663)

[Simon Pilgrim via cfe-commits]

https://github.com/RKSimon created https://github.com/llvm/llvm-project/pull/152663

None

>From 0da13f8eccff48b4f2212f341d67acab619d5a64 Mon Sep 17 00:00:00 2001
From: Simon Pilgrim <llvm-dev at redking.me.uk>
Date: Fri, 8 Aug 2025 09:23:52 +0100
Subject: [PATCH] [Headers][X86] Ensure the CONSTEXPR attributes are undefined
 at the end of the header

---
 clang/lib/Headers/avx512vpopcntdqintrin.h   | 1 +
 clang/lib/Headers/avx512vpopcntdqvlintrin.h | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/clang/lib/Headers/avx512vpopcntdqintrin.h b/clang/lib/Headers/avx512vpopcntdqintrin.h
index e24c2c5e1bcd9..79fc6e140c616 100644
--- a/clang/lib/Headers/avx512vpopcntdqintrin.h
+++ b/clang/lib/Headers/avx512vpopcntdqintrin.h
@@ -60,5 +60,6 @@ _mm512_maskz_popcnt_epi32(__mmask16 __U, __m512i __A) {
 }
 
 #undef __DEFAULT_FN_ATTRS
+#undef __DEFAULT_FN_ATTRS_CONSTEXPR
 
 #endif
diff --git a/clang/lib/Headers/avx512vpopcntdqvlintrin.h b/clang/lib/Headers/avx512vpopcntdqvlintrin.h
index b6c819b0cb85e..d14cb1eb31f14 100644
--- a/clang/lib/Headers/avx512vpopcntdqvlintrin.h
+++ b/clang/lib/Headers/avx512vpopcntdqvlintrin.h
@@ -99,5 +99,7 @@ _mm256_maskz_popcnt_epi32(__mmask8 __U, __m256i __A) {
 
 #undef __DEFAULT_FN_ATTRS128
 #undef __DEFAULT_FN_ATTRS256
+#undef __DEFAULT_FN_ATTRS128_CONSTEXPR
+#undef __DEFAULT_FN_ATTRS256_CONSTEXPR
 
 #endif