diff --git a/src/plugins/coreplugin/id.cpp b/src/plugins/coreplugin/id.cpp
index e3c329b5054..5a6b9073000 100644
--- a/src/plugins/coreplugin/id.cpp
+++ b/src/plugins/coreplugin/id.cpp
@@ -248,8 +248,7 @@ Id Id::fromSetting(const QVariant &variant)
 
 Id Id::versionedId(const QByteArray &prefix, int major, int minor)
 {
-    if (major < 0)
-        return fromName(prefix);
+    QTC_ASSERT(major >= 0, return fromName(prefix));
 
     QByteArray result = prefix + '.';
     result += QString::number(major).toLatin1();
diff --git a/src/plugins/coreplugin/id.h b/src/plugins/coreplugin/id.h
index 3f42c5fbab2..29d7cb47a75 100644
--- a/src/plugins/coreplugin/id.h
+++ b/src/plugins/coreplugin/id.h
@@ -74,7 +74,7 @@ public:
     static Id fromName(const QByteArray &ba); // FIXME: avoid.
     static Id fromSetting(const QVariant &variant); // Good to use.
 
-    static Id versionedId(const QByteArray &prefix, int major = -1, int minor = -1);
+    static Id versionedId(const QByteArray &prefix, int major, int minor = -1);
 
     static QSet<Id> fromStringList(const QStringList &list);
     static QStringList toStringList(const QSet<Id> &ids);