diff --git a/elf/elf.h b/elf/elf.h
index 1c3d5ce8a2..2b5c2c5fb6 100644
--- a/elf/elf.h
+++ b/elf/elf.h
@@ -2902,6 +2902,9 @@ enum
 #define R_AARCH64_TLSDESC      1031	/* TLS Descriptor.  */
 #define R_AARCH64_IRELATIVE	1032	/* STT_GNU_IFUNC relocation.  */
 
+/* MTE memory tag segment type.  */
+#define PT_AARCH64_MEMTAG_MTE	(PT_LOPROC + 2)
+
 /* AArch64 specific values for the Dyn d_tag field.  */
 #define DT_AARCH64_BTI_PLT	(DT_LOPROC + 1)
 #define DT_AARCH64_PAC_PLT	(DT_LOPROC + 3)