diff --git a/src/internal/poll/splice_linux.go b/src/internal/poll/splice_linux.go
index 8062d98..6869a40 100644
--- a/src/internal/poll/splice_linux.go
+++ b/src/internal/poll/splice_linux.go
@@ -158,6 +158,10 @@
 	rfd  int
 	wfd  int
 	data int
+
+	// We want to use a finalizer, so ensure that the size is
+	// large enough to not use the tiny allocator.
+	_ [24 - 3*unsafe.Sizeof(int(0))]byte
 }
 
 // splicePipePool caches pipes to avoid high-frequency construction and destruction of pipe buffers.