diff --git a/lib/dns/rdataslab_p.h b/lib/dns/rdataslab_p.h
index 2fed31a2f0..5ce39fbbc6 100644
--- a/lib/dns/rdataslab_p.h
+++ b/lib/dns/rdataslab_p.h
@@ -13,6 +13,8 @@
 
 #pragma once
 
+#include <isc/endian.h>
+
 #include <dns/rdataslab.h>
 
 #define ANCIENT(header)                                \
@@ -58,15 +60,15 @@
 	((atomic_load_acquire(&(header)->attributes) & \
 	  DNS_SLABHEADERATTR_ZEROTTL) != 0)
 
-#define peek_uint16(buffer) ({ ((uint16_t)*(buffer) << 8) | *((buffer) + 1); })
+#define peek_uint16(buffer) ISC_U8TO16_BE(buffer)
 #define get_uint16(buffer)                            \
 	({                                            \
 		uint16_t __ret = peek_uint16(buffer); \
 		buffer += sizeof(uint16_t);           \
 		__ret;                                \
 	})
-#define put_uint16(buffer, val)                  \
-	({                                       \
-		*buffer++ = (val & 0xff00) >> 8; \
-		*buffer++ = (val & 0x00ff);      \
-	})
+#define put_uint16(buffer, val)               \
+	{                                     \
+		ISC_U16TO8_BE(buffer, val);   \
+		(buffer) += sizeof(uint16_t); \
+	}