diff --git a/test/default/randombytes.c b/test/default/randombytes.c
index a518ded9..231a29bd 100644
--- a/test/default/randombytes.c
+++ b/test/default/randombytes.c
@@ -27,7 +27,9 @@ static int compat_tests(void)
 
 static int randombytes_tests(void)
 {
+    unsigned int f = 0U;
     unsigned int i;
+    uint32_t     n;
 
 #ifdef __EMSCRIPTEN__
     assert(strcmp(randombytes_implementation_name(), "sysrandom"));
@@ -35,8 +37,14 @@ static int randombytes_tests(void)
     assert(strcmp(randombytes_implementation_name(), "js"));
 #endif
     randombytes(x, 1U);
-    while (randombytes_random() <= (uint32_t) 0x7fffffff);
-    while (randombytes_random() >= (uint32_t) 0x128);
+    do {
+        n = randombytes_random();
+        f |= ((n >> 24) > 1);
+        f |= ((n >> 16) > 1) << 1;
+        f |= ((n >>  8) > 1) << 2;
+        f |= ((n      ) > 1) << 3;
+        f |= (n > 0x7fffffff) << 4;
+    } while (f != 0x1f);
     randombytes_close();
 
     for (i = 0; i < 256; ++i) {