diff --git a/ext/pg_binary_decoder.c b/ext/pg_binary_decoder.c
index ed8261905..0e39c084b 100644
--- a/ext/pg_binary_decoder.c
+++ b/ext/pg_binary_decoder.c
@@ -326,7 +326,7 @@ pg_bin_dec_timestamp(t_pg_coder *conv, const char *val, int len, int tuple, int
 			sec = (timestamp / 1000000) + 10957L * 24L * 3600L;
 			nsec = (timestamp % 1000000) * 1000;
 
-#if defined(NEGATIVE_TIME_T) && defined(SIZEOF_TIME_T) && SIZEOF_TIME_T >= 8
+#if defined(NEGATIVE_TIME_T) && SIZEOF_TIME_T >= 8
 			/* Fast path for time conversion */
 			{
 				struct timespec ts = {sec, nsec};