diff --git a/src/psbt.cpp b/src/psbt.cpp
index f31f2af0d..97bda51a6 100644
--- a/src/psbt.cpp
+++ b/src/psbt.cpp
@@ -337,7 +337,9 @@ std::string PSBTRoleName(PSBTRole role) {
     case PSBTRole::SIGNER: return "signer";
     case PSBTRole::FINALIZER: return "finalizer";
     case PSBTRole::EXTRACTOR: return "extractor";
+        // no default case, so the compiler can warn about missing cases
     }
+    assert(false);
 }
 
 bool DecodeBase64PSBT(PartiallySignedTransaction& psbt, const std::string& base64_tx, std::string& error)