From 80ec0ef3620e2830afca8645530a32117f5cfe63 Mon Sep 17 00:00:00 2001
From: Marco Barbone <mbarbone@flatironinstitute.org>
Date: Wed, 22 Jul 2026 12:10:26 -0400
Subject: [PATCH] fix: bind swizzle shuffle mask to constexpr for gcc-15

g++-15 rejects a constexpr helper call passed inline to _mm_permute_ps/
_mm_permute_pd ('the last argument must be an 8-bit immediate'). Bind the
mod_shuffle result to a constexpr local first, matching the convention used
at every other call site in the codebase.
---
 include/xsimd/arch/xsimd_avx_128.hpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/include/xsimd/arch/xsimd_avx_128.hpp b/include/xsimd/arch/xsimd_avx_128.hpp
index 4877b4ba5..b9430cab4 100644
--- a/include/xsimd/arch/xsimd_avx_128.hpp
+++ b/include/xsimd/arch/xsimd_avx_128.hpp
@@ -210,13 +210,15 @@ namespace xsimd
         template <class A, uint32_t V0, uint32_t V1, uint32_t V2, uint32_t V3>
         XSIMD_INLINE batch<float, A> swizzle(batch<float, A> const& self, batch_constant<uint32_t, A, V0, V1, V2, V3>, requires_arch<avx_128>) noexcept
         {
-            return _mm_permute_ps(self, detail::mod_shuffle(V0, V1, V2, V3));
+            constexpr auto mask = detail::mod_shuffle(V0, V1, V2, V3);
+            return _mm_permute_ps(self, mask);
         }
 
         template <class A, uint32_t V0, uint32_t V1>
         XSIMD_INLINE batch<double, A> swizzle(batch<double, A> const& self, batch_constant<uint64_t, A, V0, V1>, requires_arch<avx_128>) noexcept
         {
-            return _mm_permute_pd(self, detail::mod_shuffle(V0, V1));
+            constexpr auto mask = detail::mod_shuffle(V0, V1);
+            return _mm_permute_pd(self, mask);
         }
 
     }