diff --git a/include/onnxruntime/core/common/parse_string.h b/include/onnxruntime/core/common/parse_string.h
index 6345b2a55490d..8de9f5b467c4b 100644
--- a/include/onnxruntime/core/common/parse_string.h
+++ b/include/onnxruntime/core/common/parse_string.h
@@ -16,7 +16,7 @@ namespace onnxruntime {
 namespace detail {
 
 // Whether we will use std::from_chars() to parse to `T`.
-#if defined(_LIBCPP_VERSION)
+#if defined(_LIBCPP_VERSION) || defined(__GNUC__) && __GNUC__ < 12
 // Note: Currently (e.g., in LLVM 19), libc++'s std::from_chars() doesn't support floating point types yet.
 template <typename T>
 constexpr bool ParseWithFromChars = !std::is_same_v<bool, T> && std::is_integral_v<T>;
diff --git a/onnxruntime/contrib_ops/cpu/sparse/sparse_attention_base.h b/onnxruntime/contrib_ops/cpu/sparse/sparse_attention_base.h
index cccaec0b16ce5..4ef3a4cbe50b6 100644
--- a/onnxruntime/contrib_ops/cpu/sparse/sparse_attention_base.h
+++ b/onnxruntime/contrib_ops/cpu/sparse/sparse_attention_base.h
@@ -448,6 +448,7 @@ class SparseAttentionBase {
                        v, head_size, output_current, hidden_size,
                        MLFloat16(1.0f).val, static_cast<uint16_t>(0) /*beta*/, nullptr);
             } else {
+              (void) output_current;            // Silence gcc 9.
               size_t bytes = static_cast<size_t>(head_size) * total_seq_len * sizeof(float);
               auto v_fp32 = allocator->Alloc(bytes);
               BufferUniquePtr scratch_buffer(v_fp32, BufferDeleter(allocator));