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