diff --git a/regressions/ck_pr/validate/ck_pr_cas.c b/regressions/ck_pr/validate/ck_pr_cas.c
index fb6a5bc..2069c82 100644
--- a/regressions/ck_pr/validate/ck_pr_cas.c
+++ b/regressions/ck_pr/validate/ck_pr_cas.c
@@ -83,6 +83,11 @@ static void
 rg_width(int m)
 {
 
+	/* Other architectures are bi-endian. */
+#if !defined(__x86__) && !defined(__x86_64__)
+	return;
+#endif
+
 #ifdef CK_F_PR_CAS_64
 	if (m == 64) {
 #if defined(CK_F_PR_CAS_32)
diff --git a/regressions/ck_pr/validate/ck_pr_faa.c b/regressions/ck_pr/validate/ck_pr_faa.c
index efcb5bd..ce7bae4 100644
--- a/regressions/ck_pr/validate/ck_pr_faa.c
+++ b/regressions/ck_pr/validate/ck_pr_faa.c
@@ -85,6 +85,11 @@ static void
 rg_width(int m)
 {
 
+	/* Other architectures are bi-endian. */
+#if !defined(__x86__) && !defined(__x86_64__)
+	return;
+#endif
+
 #ifdef CK_F_PR_FAA_64
 	if (m == 64) {
 #if defined(CK_F_PR_FAA_32)
diff --git a/regressions/ck_pr/validate/ck_pr_store.c b/regressions/ck_pr/validate/ck_pr_store.c
index 5efb4d2..a76eb3b 100644
--- a/regressions/ck_pr/validate/ck_pr_store.c
+++ b/regressions/ck_pr/validate/ck_pr_store.c
@@ -76,6 +76,11 @@ static void
 rg_width(int m)
 {
 
+	/* Other architectures are bi-endian. */
+#if !defined(__x86__) && !defined(__x86_64__)
+	return;
+#endif
+
 #ifdef CK_F_PR_STORE_64
 	if (m == 64) {
 #if defined(CK_F_PR_STORE_32)