diff --git a/lib/libc/gen/__xuname.c b/lib/libc/gen/__xuname.c
--- a/lib/libc/gen/__xuname.c
+++ b/lib/libc/gen/__xuname.c
@@ -127,11 +127,11 @@
 	}
 	q += namesize;
 
-	if ((p = getenv("UNAME_m")))
+	if ((p = getenv("UNAME_p")))
 		strlcpy(q, p, namesize);
 	else {
 		mib[0] = CTL_HW;
-		mib[1] = HW_MACHINE;
+		mib[1] = HW_MACHINE_ARCH;
 		len = namesize;
 		oerrno = errno;
 		if (sysctl(mib, 2, q, &len, NULL, 0) == -1) {