Fix spurious warning spotted by -Werror

Including a real error :-)

Author: serge-sans-paille

include/xsimd/arch/generic/xsimd_generic_memory.hpp

@@ -39,7 +39,6 @@ namespace xsimd
             inline batch<IT, A> create_compress_swizzle_mask(I bitmask, ::xsimd::detail::index_sequence<Is...>)
             {
                 batch<IT, A> swizzle_mask(IT(0));
-                size_t i = 0;
                 alignas(A::alignment()) IT mask_buffer[batch<IT, A>::size] = { Is... };
                 size_t inserted = 0;
                 for (size_t i = 0; i < sizeof...(Is); ++i)

include/xsimd/arch/xsimd_avx512f.hpp

@@ -2033,10 +2033,12 @@ namespace xsimd
             XSIMD_IF_CONSTEXPR(sizeof(T) == 1)
             {
                 assert(false && "not implemented yet");
+                return {};
             }
             else XSIMD_IF_CONSTEXPR(sizeof(T) == 2)
             {
                 assert(false && "not implemented yet");
+                return {};
             }
             else XSIMD_IF_CONSTEXPR(sizeof(T) == 4)
             {
@@ -2099,10 +2101,12 @@ namespace xsimd
             XSIMD_IF_CONSTEXPR(sizeof(T) == 1)
             {
                 assert(false && "not implemented yet");
+                return {};
             }
             else XSIMD_IF_CONSTEXPR(sizeof(T) == 2)
             {
                 assert(false && "not implemented yet");
+                return {};
             }
             else XSIMD_IF_CONSTEXPR(sizeof(T) == 4)
             {

test/test_batch.cpp

@@ -101,6 +101,7 @@ struct batch_test
     {
         batch_type b;
         // value initialized to random data, can't be checked
+        (void)b;
 
         array_type tmp;
         std::fill(tmp.begin(), tmp.end(), value_type(2));

test/test_batch_bool.cpp

@@ -200,6 +200,7 @@ struct batch_bool_test
     {
         batch_bool_type a;
         // value uninitialized, cannot test it.
+        (void)a;
 
         bool_array_type res;
         batch_bool_type b(true);
@@ -368,6 +369,7 @@ struct batch_bool_test
             // FIXME: this volatile statement is useless on its own, but it
             // workaround a bug in MSVC 2022 on avx2 that shows up in CI.
             volatile auto _ = ((bool_g.half | bool_g.ihalf) == bool_g.all_true);
+            (void)_;
             INFO("operator|");
             CHECK_UNARY(res);
         }

test/test_batch_constant.cpp

@@ -125,7 +125,7 @@ struct constant_batch_test
 
         constexpr auto n12_usub = -n12;
         constexpr auto n12_usub_ = xsimd::make_batch_constant<batch_type, constant<(value_type)-12>>();
-        static_assert(std::is_same<decltype(n12_inv), decltype(n12_inv_)>::value, "-n12 == n12_usub");
+        static_assert(std::is_same<decltype(n12_usub), decltype(n12_usub_)>::value, "-n12 == n12_usub");
     }
 };
 

test/test_shuffle.cpp

@@ -323,7 +323,7 @@ struct compress_test
         for (size_t i = 0; i < size; ++i)
             mask[i] = i % 2 == 0;
 
-        for (size_t i = 0, j = 0; i < size; ++i)
+        for (size_t i = 0; i < size; ++i)
             expected[i] = i < size / 2 ? input[2 * i] : 0;
 
         auto b = xsimd::compress(
@@ -337,7 +337,7 @@ struct compress_test
         for (size_t i = 0; i < size; ++i)
             mask[i] = i % 3 == 0;
 
-        for (size_t i = 0, j = 0; i < size; ++i)
+        for (size_t i = 0; i < size; ++i)
             expected[i] = i < size / 3 ? input[3 * i] : 0;
 
         auto b = xsimd::compress(