diff --git a/library/pkcs5.c b/library/pkcs5.c
index 35146b7..a204710 100644
--- a/library/pkcs5.c
+++ b/library/pkcs5.c
@@ -249,8 +249,10 @@
     memset( counter, 0, 4 );
     counter[3] = 1;
 
+#if UINT_MAX > 0xFFFFFFFF
     if( iteration_count > 0xFFFFFFFF )
         return( MBEDTLS_ERR_PKCS5_BAD_INPUT_DATA );
+#endif
 
     while( key_length )
     {