From 122b3d46b674f8b005a7c9902e27cf3b37b109ec Mon Sep 17 00:00:00 2001
From: Harjoth Khara <harjoth.khara@gmail.com>
Date: Tue, 4 Aug 2026 07:56:33 -0700
Subject: [PATCH] [Bugfix][CPU] Fix macOS build: std::sqrt is not constexpr
 under libc++ (#50915)

Signed-off-by: harjoth <harjoth.khara@gmail.com>
---
 csrc/cpu/sgl-kernels/fla.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/csrc/cpu/sgl-kernels/fla.cpp b/csrc/cpu/sgl-kernels/fla.cpp
index 26af209a41..fec6648cec 100644
--- a/csrc/cpu/sgl-kernels/fla.cpp
+++ b/csrc/cpu/sgl-kernels/fla.cpp
@@ -101,7 +101,7 @@ struct l2norm_kernel {
     using bVec = at::vec::Vectorized<scalar_t>;
     using fVec = at::vec::Vectorized<float>;
     constexpr int bVecSize = bVec::size();
-    constexpr float scale = 1.f / std::sqrt(static_cast<float>(D));
+    const float scale = 1.f / std::sqrt(static_cast<float>(D));
 
     fVec sum_fvec0(0.f), sum_fvec1(0.f);
     int d = 0;
@@ -155,7 +155,7 @@ struct l2norm_kernel<at::BFloat16, D, has_scale> {
     __m512bh va[COLS];
     __m512 vrscale;
 
-    constexpr float scale = 1.f / std::sqrt(D);
+    const float scale = 1.f / std::sqrt(D);
     __m512 vscale = _mm512_set1_ps(scale);
 
     // step 1: load input and do reduce with avx512-bf16