diff --git a/.gitignore b/.gitignore
index 68d73096230..728a1667834 100644
--- a/.gitignore
+++ b/.gitignore
@@ -62,14 +62,17 @@ samples/server-generator/node/output/node_modules
 samples/server/petstore/nodejs/node_modules
 samples/server/petstore/nodejs-server/node_modules
 
-# qt5 cpp
-*.pro.user
-samples/client/petstore/qt5cpp/PetStore/moc_*
-samples/client/petstore/qt5cpp/PetStore/*.o
-samples/client/petstore/qt5cpp/build-*
-samples/client/petstore/qt5cpp/PetStore/PetStore
-samples/client/petstore/qt5cpp/PetStore/Makefile
-samples/client/petstore/qt5cpp/PetStore/PetStore.pro.user
+# qt cpp
+samples/client/build
+samples/client/petstore/build
+samples/client/petstore/cpp-qt/PetStore/moc_*
+samples/client/petstore/cpp-qt/PetStore/*.o
+samples/client/petstore/cpp-qt/build-*
+samples/client/petstore/cpp-qt/build-*
+samples/client/petstore/cpp-qt/PetStore/PetStore
+samples/client/petstore/cpp-qt/PetStore/Makefile
+samples/client/petstore/cpp-qt/PetStore/PetStore.pro.user
+samples/client/petstore/cpp-qt/CMakeLists.txt.user
 
 # cpprestsdk
 samples/client/petstore/cpp-restsdk/CMakeCache.txt
diff --git a/modules/openapi-generator/src/main/resources/cpp-qt-client/ServerConfiguration.mustache b/modules/openapi-generator/src/main/resources/cpp-qt-client/ServerConfiguration.mustache
index 7c2beff520b..f4e36bb4a81 100644
--- a/modules/openapi-generator/src/main/resources/cpp-qt-client/ServerConfiguration.mustache
+++ b/modules/openapi-generator/src/main/resources/cpp-qt-client/ServerConfiguration.mustache
@@ -4,9 +4,11 @@
  */
 #ifndef {{prefix}}_SERVERVCONFIGURATION_H
 #define {{prefix}}_SERVERVCONFIGURATION_H
+
 #include <QString>
 #include <QMap>
 #include <QRegularExpression>
+#include <QUrl>
 #include <stdexcept>
 #include "{{prefix}}ServerVariable.h"
 
diff --git a/modules/openapi-generator/src/main/resources/cpp-qt-client/api-body.mustache b/modules/openapi-generator/src/main/resources/cpp-qt-client/api-body.mustache
index 7fb010be106..3f7e5035d79 100644
--- a/modules/openapi-generator/src/main/resources/cpp-qt-client/api-body.mustache
+++ b/modules/openapi-generator/src/main/resources/cpp-qt-client/api-body.mustache
@@ -129,9 +129,15 @@ int {{classname}}::addServerConfiguration(const QString &operation, const QUrl &
     * @param variables A map between a variable name and its value. The value is used for substitution in the server's URL template.
     */
 void {{classname}}::setNewServerForAllOperations(const QUrl &url, const QString &description, const QMap<QString, {{prefix}}ServerVariable> &variables) {
+#if QT_VERSION >= QT_VERSION_CHECK(5, 12, 0)
     for (auto keyIt = _serverIndices.keyBegin(); keyIt != _serverIndices.keyEnd(); keyIt++) {
         setServerIndex(*keyIt, addServerConfiguration(*keyIt, url, description, variables));
     }
+#else
+    for (auto &e : _serverIndices.keys()) {
+        setServerIndex(e, addServerConfiguration(e, url, description, variables));
+    }
+#endif
 }
 
 /**
@@ -661,7 +667,7 @@ void {{classname}}::{{nickname}}({{#allParams}}{{#required}}const {{{dataType}}}
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
diff --git a/samples/client/petstore/cpp-qt/.gitignore b/samples/client/petstore/cpp-qt/.gitignore
deleted file mode 100644
index 378eac25d31..00000000000
--- a/samples/client/petstore/cpp-qt/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-build
diff --git a/samples/client/petstore/cpp-qt/PetStore/PetStore.pro b/samples/client/petstore/cpp-qt/PetStore/PetStore.pro
index 88d64d63958..961daeeeffc 100644
--- a/samples/client/petstore/cpp-qt/PetStore/PetStore.pro
+++ b/samples/client/petstore/cpp-qt/PetStore/PetStore.pro
@@ -18,6 +18,8 @@ TEMPLATE = app
 
 include(../client/PFXclient.pri)
 
+INCLUDEPATH += ../client
+
 SOURCES += main.cpp \
            PetApiTests.cpp \
            StoreApiTests.cpp \
diff --git a/samples/client/petstore/cpp-qt/client/PFXPetApi.cpp b/samples/client/petstore/cpp-qt/client/PFXPetApi.cpp
index a17deb8dfac..7c999d98687 100644
--- a/samples/client/petstore/cpp-qt/client/PFXPetApi.cpp
+++ b/samples/client/petstore/cpp-qt/client/PFXPetApi.cpp
@@ -126,9 +126,15 @@ int PFXPetApi::addServerConfiguration(const QString &operation, const QUrl &url,
     * @param variables A map between a variable name and its value. The value is used for substitution in the server's URL template.
     */
 void PFXPetApi::setNewServerForAllOperations(const QUrl &url, const QString &description, const QMap<QString, PFXServerVariable> &variables) {
+#if QT_VERSION >= QT_VERSION_CHECK(5, 12, 0)
     for (auto keyIt = _serverIndices.keyBegin(); keyIt != _serverIndices.keyEnd(); keyIt++) {
         setServerIndex(*keyIt, addServerConfiguration(*keyIt, url, description, variables));
     }
+#else
+    for (auto &e : _serverIndices.keys()) {
+        setServerIndex(e, addServerConfiguration(e, url, description, variables));
+    }
+#endif
 }
 
 /**
@@ -238,7 +244,7 @@ void PFXPetApi::addPet(const PFXPet &body) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -306,7 +312,7 @@ void PFXPetApi::deletePet(const qint64 &pet_id, const ::test_namespace::Optional
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -440,7 +446,7 @@ void PFXPetApi::findPetsByStatus(const QList<QString> &status) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -584,7 +590,7 @@ void PFXPetApi::findPetsByTags(const QList<QString> &tags) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -660,7 +666,7 @@ void PFXPetApi::getPetById(const qint64 &pet_id) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -713,7 +719,7 @@ void PFXPetApi::updatePet(const PFXPet &body) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -783,7 +789,7 @@ void PFXPetApi::updatePetWithForm(const qint64 &pet_id, const ::test_namespace::
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -853,7 +859,7 @@ void PFXPetApi::uploadFile(const qint64 &pet_id, const ::test_namespace::Optiona
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
diff --git a/samples/client/petstore/cpp-qt/client/PFXServerConfiguration.h b/samples/client/petstore/cpp-qt/client/PFXServerConfiguration.h
index 72bd32a4f6e..42e7504dcaa 100644
--- a/samples/client/petstore/cpp-qt/client/PFXServerConfiguration.h
+++ b/samples/client/petstore/cpp-qt/client/PFXServerConfiguration.h
@@ -14,9 +14,11 @@
  */
 #ifndef PFX_SERVERVCONFIGURATION_H
 #define PFX_SERVERVCONFIGURATION_H
+
 #include <QString>
 #include <QMap>
 #include <QRegularExpression>
+#include <QUrl>
 #include <stdexcept>
 #include "PFXServerVariable.h"
 
diff --git a/samples/client/petstore/cpp-qt/client/PFXStoreApi.cpp b/samples/client/petstore/cpp-qt/client/PFXStoreApi.cpp
index e0e9cc9281b..9ff025b0ad1 100644
--- a/samples/client/petstore/cpp-qt/client/PFXStoreApi.cpp
+++ b/samples/client/petstore/cpp-qt/client/PFXStoreApi.cpp
@@ -118,9 +118,15 @@ int PFXStoreApi::addServerConfiguration(const QString &operation, const QUrl &ur
     * @param variables A map between a variable name and its value. The value is used for substitution in the server's URL template.
     */
 void PFXStoreApi::setNewServerForAllOperations(const QUrl &url, const QString &description, const QMap<QString, PFXServerVariable> &variables) {
+#if QT_VERSION >= QT_VERSION_CHECK(5, 12, 0)
     for (auto keyIt = _serverIndices.keyBegin(); keyIt != _serverIndices.keyEnd(); keyIt++) {
         setServerIndex(*keyIt, addServerConfiguration(*keyIt, url, description, variables));
     }
+#else
+    for (auto &e : _serverIndices.keys()) {
+        setServerIndex(e, addServerConfiguration(e, url, description, variables));
+    }
+#endif
 }
 
 /**
@@ -240,7 +246,7 @@ void PFXStoreApi::deleteOrder(const QString &order_id) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -292,7 +298,7 @@ void PFXStoreApi::getInventory() {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -364,7 +370,7 @@ void PFXStoreApi::getOrderById(const qint64 &order_id) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -417,7 +423,7 @@ void PFXStoreApi::placeOrder(const PFXOrder &body) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
diff --git a/samples/client/petstore/cpp-qt/client/PFXUserApi.cpp b/samples/client/petstore/cpp-qt/client/PFXUserApi.cpp
index cc38ec0bb08..b2f4d4ff96d 100644
--- a/samples/client/petstore/cpp-qt/client/PFXUserApi.cpp
+++ b/samples/client/petstore/cpp-qt/client/PFXUserApi.cpp
@@ -126,9 +126,15 @@ int PFXUserApi::addServerConfiguration(const QString &operation, const QUrl &url
     * @param variables A map between a variable name and its value. The value is used for substitution in the server's URL template.
     */
 void PFXUserApi::setNewServerForAllOperations(const QUrl &url, const QString &description, const QMap<QString, PFXServerVariable> &variables) {
+#if QT_VERSION >= QT_VERSION_CHECK(5, 12, 0)
     for (auto keyIt = _serverIndices.keyBegin(); keyIt != _serverIndices.keyEnd(); keyIt++) {
         setServerIndex(*keyIt, addServerConfiguration(*keyIt, url, description, variables));
     }
+#else
+    for (auto &e : _serverIndices.keys()) {
+        setServerIndex(e, addServerConfiguration(e, url, description, variables));
+    }
+#endif
 }
 
 /**
@@ -238,7 +244,7 @@ void PFXUserApi::createUser(const PFXUser &body) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -290,7 +296,7 @@ void PFXUserApi::createUsersWithArrayInput(const QList<PFXUser> &body) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -342,7 +348,7 @@ void PFXUserApi::createUsersWithListInput(const QList<PFXUser> &body) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -404,7 +410,7 @@ void PFXUserApi::deleteUser(const QString &username) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -466,7 +472,7 @@ void PFXUserApi::getUserByName(const QString &username) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -546,7 +552,7 @@ void PFXUserApi::loginUser(const QString &username, const QString &password) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -596,7 +602,7 @@ void PFXUserApi::logoutUser() {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif
@@ -662,7 +668,7 @@ void PFXUserApi::updateUser(const QString &username, const PFXUser &body) {
         input.headers.insert(keyValueIt->first, keyValueIt->second);
     }
 #else
-    for (auto key = _defaultHeaders.keys()) {
+    for (auto key : _defaultHeaders.keys()) {
         input.headers.insert(key, _defaultHeaders[key]);
     }
 #endif