diff --git a/gui/cppchecklibrarydata.cpp b/gui/cppchecklibrarydata.cpp
index 6c513c395dba..23291e5da1a1 100644
--- a/gui/cppchecklibrarydata.cpp
+++ b/gui/cppchecklibrarydata.cpp
@@ -617,7 +617,7 @@ static void writeFunction(QXmlStreamWriter &xmlWriter, const CppcheckLibraryData
         xmlWriter.writeEndElement();
     }
     if (function.noreturn != CppcheckLibraryData::Function::Unknown)
-        xmlWriter.writeTextElement("noreturn", QString::fromStdString(bool_to_string(function.noreturn == CppcheckLibraryData::Function::True)));
+        xmlWriter.writeTextElement("noreturn", bool_to_string(function.noreturn == CppcheckLibraryData::Function::True));
     if (function.leakignore)
         xmlWriter.writeEmptyElement("leak-ignore");
     // Argument info..
@@ -721,7 +721,7 @@ static void writeMemoryResource(QXmlStreamWriter &xmlWriter, const CppcheckLibra
         } else {
             xmlWriter.writeStartElement("alloc");
         }
-        xmlWriter.writeAttribute("init", QString::fromStdString(bool_to_string(alloc.init)));
+        xmlWriter.writeAttribute("init", bool_to_string(alloc.init));
         if (alloc.arg != -1) {
             xmlWriter.writeAttribute("arg", QString("%1").arg(alloc.arg));
         }
diff --git a/gui/librarydialog.cpp b/gui/librarydialog.cpp
index 381a569ff24a..506cb6bc1376 100644
--- a/gui/librarydialog.cpp
+++ b/gui/librarydialog.cpp
@@ -344,11 +344,11 @@ QString LibraryDialog::getArgText(const CppcheckLibraryData::Function::Arg &arg)
     if (arg.nr != CppcheckLibraryData::Function::Arg::ANY)
         s += QString::number(arg.nr);
 
-    s += "\n    not bool: " + QString::fromStdString(bool_to_string(arg.notbool));
-    s += "\n    not null: " +  QString::fromStdString(bool_to_string(arg.notnull));
-    s += "\n    not uninit: " +  QString::fromStdString(bool_to_string(arg.notuninit));
-    s += "\n    format string: " +  QString::fromStdString(bool_to_string(arg.formatstr));
-    s += "\n    strz: " +  QString::fromStdString(bool_to_string(arg.strz));
+    s += "\n    not bool: " + QString(bool_to_string(arg.notbool));
+    s += "\n    not null: " +  QString(bool_to_string(arg.notnull));
+    s += "\n    not uninit: " +  QString(bool_to_string(arg.notuninit));
+    s += "\n    format string: " +  QString(bool_to_string(arg.formatstr));
+    s += "\n    strz: " +  QString(bool_to_string(arg.strz));
     s += "\n    valid: " + QString(arg.valid.isEmpty() ? "any" : arg.valid);
     for (const CppcheckLibraryData::Function::Arg::MinSize &minsize : arg.minsizes) {
         s += "\n    minsize: " + minsize.type + " " + minsize.arg + " " + minsize.arg2;
diff --git a/gui/projectfile.cpp b/gui/projectfile.cpp
index 07e60c8baa25..5899f1c7ebd8 100644
--- a/gui/projectfile.cpp
+++ b/gui/projectfile.cpp
@@ -848,7 +848,7 @@ bool ProjectFile::write(const QString &filename)
     }
 
     xmlWriter.writeStartElement(CppcheckXml::AnalyzeAllVsConfigsElementName);
-    xmlWriter.writeCharacters(QString::fromStdString(bool_to_string(mAnalyzeAllVsConfigs)));
+    xmlWriter.writeCharacters(bool_to_string(mAnalyzeAllVsConfigs));
     xmlWriter.writeEndElement();
 
     if (clangParser) {
diff --git a/lib/checkcondition.cpp b/lib/checkcondition.cpp
index ff9a42e948f8..d0e2e6d92fe0 100644
--- a/lib/checkcondition.cpp
+++ b/lib/checkcondition.cpp
@@ -244,7 +244,7 @@ void CheckCondition::assignIfError(const Token *tok1, const Token *tok2, const s
     reportError(locations,
                 Severity::style,
                 "assignIfError",
-                "Mismatching assignment and comparison, comparison '" + condition + "' is always " + bool_to_string(result) + ".", CWE398, Certainty::normal);
+                "Mismatching assignment and comparison, comparison '" + condition + "' is always " + std::string(bool_to_string(result)) + ".", CWE398, Certainty::normal);
 }
 
 
diff --git a/lib/utils.h b/lib/utils.h
index 46ee7d698612..eca1f0e2abb3 100644
--- a/lib/utils.h
+++ b/lib/utils.h
@@ -314,7 +314,7 @@ static inline std::string id_string(const void* p)
     return id_string_i(reinterpret_cast<uintptr_t>(p));
 }
 
-static inline std::string bool_to_string(bool b)
+static inline const char* bool_to_string(bool b)
 {
     return b ? "true" : "false";
 }