diff --git a/src/key.cpp b/src/key.cpp
--- a/src/key.cpp
+++ b/src/key.cpp
@@ -315,7 +315,7 @@
         secp256k1_context_sign, &sig, hash.begin(), begin(),
         secp256k1_nonce_function_rfc6979, nullptr);
     assert(ret);
-    secp256k1_ecdsa_recoverable_signature_serialize_compact(
+    ret = secp256k1_ecdsa_recoverable_signature_serialize_compact(
         secp256k1_context_sign, &vchSig[1], &rec, &sig);
     assert(ret);
     assert(rec != -1);