diff --git a/stepmania/src/crypto51/misc.h b/stepmania/src/crypto51/misc.h
index f212ba13fa..34dcce9c85 100644
--- a/stepmania/src/crypto51/misc.h
+++ b/stepmania/src/crypto51/misc.h
@@ -140,6 +140,10 @@ inline unsigned int GetAlignment(T *dummy=NULL)	// VC60 workaround
 #endif
 }
 
+#if !defined(uintptr_t)
+typedef unsigned int uintptr_t;
+#endif
+
 inline bool IsAlignedOn(const void *p, unsigned int alignment)
 {
 	return IsPowerOf2(alignment) ? ModPowerOf2((uintptr_t)p, alignment) == 0 : (uintptr_t)p % alignment == 0;