diff --git a/tests/unit/unit3214.c b/tests/unit/unit3214.c
index 8f22f53cc6..191ef2f3f6 100644
--- a/tests/unit/unit3214.c
+++ b/tests/unit/unit3214.c
@@ -26,6 +26,11 @@
 
 static void checksize(const char *name, size_t size, size_t allowed)
 {
+  /* Some platforms, e.g., CHERI, have 128-bit pointers. Allow structs to be
+     double the size of what we would typically expect. */
+  if(sizeof(void *) > 8)
+    allowed *= sizeof(void *) / 8;
+
   if(size > allowed) {
     curl_mfprintf(stderr, "BAD: struct %s is %zu bytes, "
                   "allowed to be %zu: %zu bytes too big\n",
@@ -39,7 +44,8 @@ static void checksize(const char *name, size_t size, size_t allowed)
   }
 }
 
-/* the maximum sizes we allow specific structs to grow to */
+/* The maximum sizes we allow specific structs to grow to.
+   These sizes were chosen with platforms with 64-bit pointers in mind. */
 #define MAX_CURL_EASY           5370
 #define MAX_CONNECTDATA         1300
 #define MAX_CURL_MULTI          850