Index: src/yencode/platform.cc
--- src/yencode/platform.cc.orig
+++ src/yencode/platform.cc
@@ -19,7 +19,7 @@
 # endif
 bool RapidYenc::cpu_supports_neon() {
 # if defined(AT_HWCAP)
-#  ifdef __FreeBSD__
+#  if defined(__FreeBSD__) || defined(__OpenBSD__)
 	unsigned long supported;
 	elf_aux_info(AT_HWCAP, &supported, sizeof(supported));
 #   ifdef __aarch64__
@@ -204,7 +204,7 @@ int RapidYenc::cpu_supports_crc_isa() {
 bool RapidYenc::cpu_supports_rvv() {
 # if defined(AT_HWCAP)
 	unsigned long ret;
-#  ifdef __FreeBSD__
+#  if defined(__FreeBSD__) || defined(__OpenBSD__)
 	elf_aux_info(AT_HWCAP, &ret, sizeof(ret));
 #  else
 	ret = getauxval(AT_HWCAP);
