diff --git a/lib/checkstl.cpp b/lib/checkstl.cpp
index 7f39a6c50..08960bc6b 100644
--- a/lib/checkstl.cpp
+++ b/lib/checkstl.cpp
@@ -601,5 +601,6 @@ void CheckStl::size()
 void CheckStl::sizeError(const Token *tok)
 {
     const std::string varname(tok ? tok->str().c_str() : "list");
-    reportError(tok, Severity::possibleStyle, "stlSize", "Use " + varname + ".empty() instead of " + varname + ".size() to guarantee fast code." + (_settings->_verbose ? " size() can take linear time but empty() is guaranteed to take constant time." : ""));
+    const bool verbose(_settings ? _settings->_verbose : true);
+    reportError(tok, Severity::possibleStyle, "stlSize", "Use " + varname + ".empty() instead of " + varname + ".size() to guarantee fast code." + (verbose ? " size() can take linear time but empty() is guaranteed to take constant time." : ""));
 }