diff --git a/src/secp256k1/src/tests.c b/src/secp256k1/src/tests.c
--- a/src/secp256k1/src/tests.c
+++ b/src/secp256k1/src/tests.c
@@ -4451,7 +4451,9 @@
             seed16[6] ^= t >> 48;
             seed16[7] ^= t >> 56;
         }
-        fclose(frand);
+        if (frand) {
+            fclose(frand);
+        }
     }
     secp256k1_rand_seed(seed16);