diff --git a/qmake/generators/integrity/gbuild.cpp b/qmake/generators/integrity/gbuild.cpp
index 0d9d81c549..a587cf1c8e 100644
--- a/qmake/generators/integrity/gbuild.cpp
+++ b/qmake/generators/integrity/gbuild.cpp
@@ -259,8 +259,8 @@ GBuildMakefileGenerator::write()
         t << "\t-Iwork\n";
         t << "\t-Llib\n";
         t << "\t";
-        QStringList &l = project->values("QMAKE_CXXFLAGS");
-        for (QStringList::Iterator it = l.begin(); it != l.end(); ++it) {
+        const QStringList &l = project->values("QMAKE_CXXFLAGS");
+        for (QStringList::ConstIterator it = l.begin(); it != l.end(); ++it) {
             if ((*it).startsWith("-"))
                 t << "\n" << "\t" << (*it);
             else
@@ -285,8 +285,8 @@ GBuildMakefileGenerator::write()
             if (isnativebin && (i == 0))
                 continue;
             t << "\t";
-            QStringList &l = project->values(src[i]);
-            for (QStringList::Iterator it = l.begin(); it != l.end(); ++it) {
+            const QStringList &l = project->values(src[i]);
+            for (QStringList::ConstIterator it = l.begin(); it != l.end(); ++it) {
                 if ((*it).startsWith("-"))
                     t << "\n" << "\t" << (*it);
                 else
@@ -298,8 +298,8 @@ GBuildMakefileGenerator::write()
 
     /* first subdirectories/subprojects */
     {
-        QStringList &l = project->values("SUBDIRS");
-        for (QStringList::Iterator it = l.begin(); it != l.end(); ++it) {
+        const QStringList &l = project->values("SUBDIRS");
+        for (QStringList::ConstIterator it = l.begin(); it != l.end(); ++it) {
             QString gpjname((*it));
             /* avoid native tools */
             if (nativebins.contains(gpjname.section("_", -1)))
@@ -319,9 +319,10 @@ GBuildMakefileGenerator::write()
     }
 
     {
-        QStringList &l = project->values("RESOURCES");
-        for (QStringList::Iterator it = l.begin(); it != l.end(); ++it) {
-            QString tmpstr((*it).replace(pathtoremove, ""));
+        const QStringList &l = project->values("RESOURCES");
+        for (QStringList::ConstIterator it = l.begin(); it != l.end(); ++it) {
+            QString tmpstr(*it);
+            tmpstr.remove(pathtoremove);
             t << tmpstr << "\t[Qt Resource]\n";
             tmpstr = tmpstr.section(".", -2, -1).section(QDir::separator(), -1);
             tmpstr.remove(".qrc");
@@ -332,9 +333,10 @@ GBuildMakefileGenerator::write()
         }
     }
     {
-        QStringList &l = project->values("FORMS");
-        for (QStringList::Iterator it = l.begin(); it != l.end(); ++it) {
-            QString tmpstr((*it).replace(pathtoremove, ""));
+        const QStringList &l = project->values("FORMS");
+        for (QStringList::ConstIterator it = l.begin(); it != l.end(); ++it) {
+            QString tmpstr(*it);
+            tmpstr.remove(pathtoremove);
             t << tmpstr << "\t[Qt Dialog]\n";
             tmpstr = tmpstr.section(".", 0, 0).section(QDir::separator(), -1);
             tmpstr.insert(tmpstr.lastIndexOf(QDir::separator()) + 1, "ui_");
@@ -347,22 +349,22 @@ GBuildMakefileGenerator::write()
     /* source files for this project */
     QString src[] = { "HEADERS", "SOURCES", QString() };
     for (int i = 0; !src[i].isNull(); i++) {
-        QStringList &l = project->values(src[i]);
-        for (QStringList::Iterator it = l.begin(); it != l.end(); ++it) {
+        const QStringList &l = project->values(src[i]);
+        for (QStringList::ConstIterator it = l.begin(); it != l.end(); ++it) {
             if ((*it).isEmpty())
                 continue;
             /* native tools aren't preprocessed */
             if (!isnativebin)
                 t << writeOne((*it), pathtoremove);
             else
-                t << (*it).remove(pathtoremove) << "\n";
+                t << QString(*it).remove(pathtoremove) << "\n";
         }
     }
     t << "\n";
 
     {
-        QStringList &l = project->values("GENERATED_SOURCES");
-        for (QStringList::Iterator it = l.begin(); it != l.end(); ++it) {
+        const QStringList &l = project->values("GENERATED_SOURCES");
+        for (QStringList::ConstIterator it = l.begin(); it != l.end(); ++it) {
             t << "work/" << (*it).section(QDir::separator(), -1) << "\n";
         }
     }
diff --git a/qmake/generators/mac/pbuilder_pbx.cpp b/qmake/generators/mac/pbuilder_pbx.cpp
index 80c220ed2b..b1b4c4381f 100644
--- a/qmake/generators/mac/pbuilder_pbx.cpp
+++ b/qmake/generators/mac/pbuilder_pbx.cpp
@@ -393,7 +393,7 @@ ProjectBuilderMakefileGenerator::writeSubDirs(QTextStream &t)
     t << "\t\t\t" << writeSettings("buildConfigurationList", keyFor("QMAKE_SUBDIR_PBX_BUILDCONFIG_LIST")) << ";" << "\n";
     t << "\t\t\t" << "projectReferences = (" << "\n";
     {
-        QStringList &qmake_subdirs = project->values("QMAKE_PBX_SUBDIRS");
+        const QStringList &qmake_subdirs = project->values("QMAKE_PBX_SUBDIRS");
         for(int i = 0; i < qmake_subdirs.count(); i++) {
             QString subdir = qmake_subdirs[i];
             t << "\t\t\t\t" << "{" << "\n"
@@ -714,16 +714,16 @@ ProjectBuilderMakefileGenerator::writeMakeParts(QTextStream &t)
             mkt << "IMAGES = " << varList("QMAKE_IMAGE_COLLECTION") << endl;
             mkt << "PARSERS =";
             if(!project->isEmpty("YACCSOURCES")) {
-                QStringList &yaccs = project->values("YACCSOURCES");
-                for(QStringList::Iterator yit = yaccs.begin(); yit != yaccs.end(); ++yit) {
+                const QStringList &yaccs = project->values("YACCSOURCES");
+                for (QStringList::ConstIterator yit = yaccs.begin(); yit != yaccs.end(); ++yit) {
                     QFileInfo fi(fileInfo((*yit)));
                     mkt << " " << fi.path() << Option::dir_sep << fi.baseName()
                         << Option::yacc_mod << Option::cpp_ext.first();
                 }
             }
             if(!project->isEmpty("LEXSOURCES")) {
-                QStringList &lexs = project->values("LEXSOURCES");
-                for(QStringList::Iterator lit = lexs.begin(); lit != lexs.end(); ++lit) {
+                const QStringList &lexs = project->values("LEXSOURCES");
+                for (QStringList::ConstIterator lit = lexs.begin(); lit != lexs.end(); ++lit) {
                     QFileInfo fi(fileInfo((*lit)));
                     mkt << " " << fi.path() << Option::dir_sep << fi.baseName()
                         << Option::lex_mod << Option::cpp_ext.first();
diff --git a/qmake/generators/makefile.cpp b/qmake/generators/makefile.cpp
index ca22655171..89ee6a3d92 100644
--- a/qmake/generators/makefile.cpp
+++ b/qmake/generators/makefile.cpp
@@ -671,7 +671,7 @@ MakefileGenerator::init()
         if(tmp_out.isEmpty())
             continue;
         if(project->values((*it) + ".CONFIG").indexOf("combine") != -1) {
-            QStringList &compilerInputs = project->values((*it) + ".input");
+            const QStringList &compilerInputs = project->values((*it) + ".input");
             // Don't generate compiler output if it doesn't have input.
             if (compilerInputs.isEmpty() || project->values(compilerInputs.first()).isEmpty())
                 continue;
@@ -709,8 +709,8 @@ MakefileGenerator::init()
                 }
             }
         } else {
-            QStringList &tmp = project->values((*it) + ".input");
-            for(QStringList::Iterator it2 = tmp.begin(); it2 != tmp.end(); ++it2) {
+            const QStringList &tmp = project->values((*it) + ".input");
+            for (QStringList::ConstIterator it2 = tmp.begin(); it2 != tmp.end(); ++it2) {
                 const QStringList inputs = project->values((*it2));
                 for(QStringList::ConstIterator input = inputs.constBegin(); input != inputs.constEnd(); ++input) {
                     if((*input).isEmpty())
@@ -1157,11 +1157,11 @@ MakefileGenerator::writePrlFile()
 void
 MakefileGenerator::writeObj(QTextStream &t, const QString &src)
 {
-    QStringList &srcl = project->values(src);
-    QStringList objl = createObjectList(srcl);
+    const QStringList &srcl = project->values(src);
+    const QStringList objl = createObjectList(srcl);
 
-    QStringList::Iterator oit = objl.begin();
-    QStringList::Iterator sit = srcl.begin();
+    QStringList::ConstIterator oit = objl.begin();
+    QStringList::ConstIterator sit = srcl.begin();
     QString stringSrc("$src");
     QString stringObj("$obj");
     for(;sit != srcl.end() && oit != objl.end(); ++oit, ++sit) {
@@ -1222,8 +1222,8 @@ MakefileGenerator::writeInstalls(QTextStream &t, const QString &installs, bool n
         rm_dir_contents = "-$(DEL_FILE) -r";
 
     QString all_installs, all_uninstalls;
-    QStringList &l = project->values(installs);
-    for(QStringList::Iterator it = l.begin(); it != l.end(); ++it) {
+    const QStringList &l = project->values(installs);
+    for (QStringList::ConstIterator it = l.begin(); it != l.end(); ++it) {
         QString pvar = (*it) + ".path";
         if(project->values((*it) + ".CONFIG").indexOf("no_path") == -1 &&
            project->values((*it) + ".CONFIG").indexOf("dummy_install") == -1 &&
@@ -1689,10 +1689,10 @@ MakefileGenerator::verifyExtraCompiler(const QString &comp, const QString &file_
                 if(!pass)
                     return false;
             } else {
-                QStringList &tmp = project->values(comp + ".input");
-                for(QStringList::Iterator it = tmp.begin(); it != tmp.end(); ++it) {
-                    QStringList &inputs = project->values((*it));
-                    for(QStringList::Iterator input = inputs.begin(); input != inputs.end(); ++input) {
+                const QStringList &tmp = project->values(comp + ".input");
+                for (QStringList::ConstIterator it = tmp.begin(); it != tmp.end(); ++it) {
+                    const QStringList &inputs = project->values((*it));
+                    for (QStringList::ConstIterator input = inputs.begin(); input != inputs.end(); ++input) {
                         if((*input).isEmpty())
                             continue;
                         QString in = fileFixify(Option::fixPathToTargetOS((*input), false));
@@ -1735,10 +1735,10 @@ MakefileGenerator::verifyExtraCompiler(const QString &comp, const QString &file_
             if(system(cmd.toLatin1().constData()))
                 return false;
         } else {
-            QStringList &tmp = project->values(comp + ".input");
-            for(QStringList::Iterator it = tmp.begin(); it != tmp.end(); ++it) {
-                QStringList &inputs = project->values((*it));
-                for(QStringList::Iterator input = inputs.begin(); input != inputs.end(); ++input) {
+            const QStringList &tmp = project->values(comp + ".input");
+            for (QStringList::ConstIterator it = tmp.begin(); it != tmp.end(); ++it) {
+                const QStringList &inputs = project->values((*it));
+                for (QStringList::ConstIterator input = inputs.begin(); input != inputs.end(); ++input) {
                     if((*input).isEmpty())
                         continue;
                     QString in = fileFixify(Option::fixPathToTargetOS((*input), false));
@@ -1759,14 +1759,14 @@ MakefileGenerator::verifyExtraCompiler(const QString &comp, const QString &file_
 void
 MakefileGenerator::writeExtraTargets(QTextStream &t)
 {
-    QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
-    for(QStringList::Iterator it = qut.begin(); it != qut.end(); ++it) {
+    const QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
+    for (QStringList::ConstIterator it = qut.begin(); it != qut.end(); ++it) {
         QString targ = var((*it) + ".target"),
                  cmd = var((*it) + ".commands"), deps;
         if(targ.isEmpty())
             targ = (*it);
-        QStringList &deplist = project->values((*it) + ".depends");
-        for(QStringList::Iterator dep_it = deplist.begin(); dep_it != deplist.end(); ++dep_it) {
+        const QStringList &deplist = project->values((*it) + ".depends");
+        for (QStringList::ConstIterator dep_it = deplist.begin(); dep_it != deplist.end(); ++dep_it) {
             QString dep = var((*dep_it) + ".target");
             if(dep.isEmpty())
                 dep = (*dep_it);
@@ -1828,7 +1828,7 @@ MakefileGenerator::writeExtraCompilerTargets(QTextStream &t)
                  + escapeFilePath(Option::fixPathToLocalOS(Option::output_dir, false))
                  + QLatin1String(" && ");
         }
-        QStringList &vars = project->values((*it) + ".variables");
+        const QStringList &vars = project->values((*it) + ".variables");
         if(tmp_out.isEmpty() || tmp_cmd.isEmpty())
             continue;
         QStringList tmp_inputs;
@@ -2120,10 +2120,10 @@ MakefileGenerator::writeExtraVariables(QTextStream &t)
     t << endl;
 
     QStringList outlist;
-    QHash<QString, QStringList> &vars = project->variables();
-    QStringList &exports = project->values("QMAKE_EXTRA_VARIABLES");
-    for (QHash<QString, QStringList>::Iterator it = vars.begin(); it != vars.end(); ++it) {
-        for (QStringList::Iterator exp_it = exports.begin(); exp_it != exports.end(); ++exp_it) {
+    const QHash<QString, QStringList> &vars = project->variables();
+    const QStringList &exports = project->values("QMAKE_EXTRA_VARIABLES");
+    for (QHash<QString, QStringList>::ConstIterator it = vars.begin(); it != vars.end(); ++it) {
+        for (QStringList::ConstIterator exp_it = exports.begin(); exp_it != exports.end(); ++exp_it) {
             QRegExp rx((*exp_it), Qt::CaseInsensitive, QRegExp::Wildcard);
             if (rx.exactMatch(it.key()))
                 outlist << ("EXPORT_" + it.key() + " = " + it.value().join(" "));
@@ -2139,7 +2139,7 @@ bool
 MakefileGenerator::writeStubMakefile(QTextStream &t)
 {
     t << "QMAKE    = " << var("QMAKE_QMAKE") << endl;
-    QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
+    const QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
     for(QStringList::ConstIterator it = qut.begin(); it != qut.end(); ++it)
         t << *it << " ";
     //const QString ofile = Option::fixPathToTargetOS(fileFixify(Option::output.fileName()));
@@ -2396,8 +2396,8 @@ void
 MakefileGenerator::writeSubTargets(QTextStream &t, QList<MakefileGenerator::SubTarget*> targets, int flags)
 {
     // blasted includes
-    QStringList &qeui = project->values("QMAKE_EXTRA_INCLUDES");
-    for(QStringList::Iterator qeui_it = qeui.begin(); qeui_it != qeui.end(); ++qeui_it)
+    const QStringList &qeui = project->values("QMAKE_EXTRA_INCLUDES");
+    for (QStringList::ConstIterator qeui_it = qeui.begin(); qeui_it != qeui.end(); ++qeui_it)
         t << "include " << (*qeui_it) << endl;
 
     if (!(flags & SubTargetSkipDefaultVariables)) {
@@ -2607,16 +2607,16 @@ MakefileGenerator::writeSubTargets(QTextStream &t, QList<MakefileGenerator::SubT
     }
 
     // user defined targets
-    QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
-    for(QStringList::Iterator qut_it = qut.begin(); qut_it != qut.end(); ++qut_it) {
+    const QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
+    for (QStringList::ConstIterator qut_it = qut.begin(); qut_it != qut.end(); ++qut_it) {
         QString targ = var((*qut_it) + ".target"),
                  cmd = var((*qut_it) + ".commands"), deps;
         if(targ.isEmpty())
             targ = (*qut_it);
         t << endl;
 
-        QStringList &deplist = project->values((*qut_it) + ".depends");
-        for(QStringList::Iterator dep_it = deplist.begin(); dep_it != deplist.end(); ++dep_it) {
+        const QStringList &deplist = project->values((*qut_it) + ".depends");
+        for (QStringList::ConstIterator dep_it = deplist.begin(); dep_it != deplist.end(); ++dep_it) {
             QString dep = var((*dep_it) + ".target");
             if(dep.isEmpty())
                 dep = Option::fixPathToTargetOS(*dep_it, false);
@@ -2931,8 +2931,8 @@ MakefileGenerator::checkMultipleDefinition(const QString &f, const QString &w)
     int slsh = f.lastIndexOf(Option::dir_sep);
     if(slsh != -1)
         file.remove(0, slsh + 1);
-    QStringList &l = project->values(w);
-    for(QStringList::Iterator val_it = l.begin(); val_it != l.end(); ++val_it) {
+    const QStringList &l = project->values(w);
+    for (QStringList::ConstIterator val_it = l.begin(); val_it != l.end(); ++val_it) {
         QString file2((*val_it));
         slsh = file2.lastIndexOf(Option::dir_sep);
         if(slsh != -1)
@@ -2965,8 +2965,8 @@ MakefileGenerator::findFileForDep(const QMakeLocalFileName &dep, const QMakeLoca
     QMakeLocalFileName ret;
     if(!project->isEmpty("SKIP_DEPENDS")) {
         bool found = false;
-        QStringList &nodeplist = project->values("SKIP_DEPENDS");
-        for(QStringList::Iterator it = nodeplist.begin();
+        const QStringList &nodeplist = project->values("SKIP_DEPENDS");
+        for (QStringList::ConstIterator it = nodeplist.begin();
             it != nodeplist.end(); ++it) {
             QRegExp regx((*it));
             if(regx.indexIn(dep.local()) != -1) {
@@ -3014,8 +3014,8 @@ MakefileGenerator::findFileForDep(const QMakeLocalFileName &dep, const QMakeLoca
         }
         { //is it from an EXTRA_TARGET
             const QString dep_basename = dep.local().section(Option::dir_sep, -1);
-            QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
-            for(QStringList::Iterator it = qut.begin(); it != qut.end(); ++it) {
+            const QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
+            for (QStringList::ConstIterator it = qut.begin(); it != qut.end(); ++it) {
                 QString targ = var((*it) + ".target");
                 if(targ.isEmpty())
                     targ = (*it);
@@ -3033,10 +3033,10 @@ MakefileGenerator::findFileForDep(const QMakeLocalFileName &dep, const QMakeLoca
                 QString tmp_out = project->values((*it) + ".output").first();
                 if(tmp_out.isEmpty())
                     continue;
-                QStringList &tmp = project->values((*it) + ".input");
-                for(QStringList::Iterator it2 = tmp.begin(); it2 != tmp.end(); ++it2) {
-                    QStringList &inputs = project->values((*it2));
-                    for(QStringList::Iterator input = inputs.begin(); input != inputs.end(); ++input) {
+                const QStringList &tmp = project->values((*it) + ".input");
+                for (QStringList::ConstIterator it2 = tmp.begin(); it2 != tmp.end(); ++it2) {
+                    const QStringList &inputs = project->values((*it2));
+                    for (QStringList::ConstIterator input = inputs.begin(); input != inputs.end(); ++input) {
                         QString out = Option::fixPathToTargetOS(unescapeFilePath(replaceExtraCompilerVariables(tmp_out, (*input), QString())));
               if(out == dep.real() || out.section(Option::dir_sep, -1) == dep_basename) {
                             ret = QMakeLocalFileName(fileFixify(out, qmake_getpwd(), Option::output_dir));
diff --git a/qmake/generators/unix/unixmake.cpp b/qmake/generators/unix/unixmake.cpp
index 02f8666bbb..31b059decc 100644
--- a/qmake/generators/unix/unixmake.cpp
+++ b/qmake/generators/unix/unixmake.cpp
@@ -742,7 +742,7 @@ UnixMakefileGenerator::defaultInstall(const QString &t)
 
     QStringList links;
     QString target="$(TARGET)";
-    QStringList &targets = project->values(t + ".targets");
+    const QStringList &targets = project->values(t + ".targets");
     if(!project->isEmpty("QMAKE_BUNDLE")) {
         target = project->first("QMAKE_BUNDLE");
         bundle = true;
diff --git a/qmake/generators/unix/unixmake2.cpp b/qmake/generators/unix/unixmake2.cpp
index 490b76e494..f13699f0f7 100644
--- a/qmake/generators/unix/unixmake2.cpp
+++ b/qmake/generators/unix/unixmake2.cpp
@@ -82,7 +82,7 @@ UnixMakefileGenerator::writeMakefile(QTextStream &t)
     writeHeader(t);
     if(!project->values("QMAKE_FAILED_REQUIREMENTS").isEmpty()) {
         t << "QMAKE    = " << var("QMAKE_QMAKE") << endl;
-        QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
+        const QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
         for(QStringList::ConstIterator it = qut.begin(); it != qut.end(); ++it)
             t << *it << " ";
         t << "first all clean install distclean uninstall qmake_all:" << "\n\t"
@@ -190,11 +190,13 @@ UnixMakefileGenerator::writeMakeParts(QTextStream &t)
     t << "SOURCES       = " << valList(escapeFilePaths(project->values("SOURCES"))) << " "
       << valList(escapeFilePaths(project->values("GENERATED_SOURCES"))) << endl;
     if(do_incremental) {
-        QStringList &objs = project->values("OBJECTS"), &incrs = project->values("QMAKE_INCREMENTAL"), incrs_out;
+        const QStringList &objs = project->values("OBJECTS");
+        const QStringList &incrs = project->values("QMAKE_INCREMENTAL");
+        QStringList incrs_out;
         t << "OBJECTS       = ";
-        for(QStringList::Iterator objit = objs.begin(); objit != objs.end(); ++objit) {
+        for (QStringList::ConstIterator objit = objs.begin(); objit != objs.end(); ++objit) {
             bool increment = false;
-            for(QStringList::Iterator incrit = incrs.begin(); incrit != incrs.end(); ++incrit) {
+            for (QStringList::ConstIterator incrit = incrs.begin(); incrit != incrs.end(); ++incrit) {
                 if((*objit).indexOf(QRegExp((*incrit), Qt::CaseSensitive,
                                     QRegExp::Wildcard)) != -1) {
                     increment = true;
@@ -247,8 +249,8 @@ UnixMakefileGenerator::writeMakeParts(QTextStream &t)
     t << endl;
 
     // blasted includes
-    QStringList &qeui = project->values("QMAKE_EXTRA_INCLUDES");
-    QStringList::Iterator it;
+    const QStringList &qeui = project->values("QMAKE_EXTRA_INCLUDES");
+    QStringList::ConstIterator it;
     for(it = qeui.begin(); it != qeui.end(); ++it)
         t << "include " << (*it) << endl;
 
@@ -301,8 +303,8 @@ UnixMakefileGenerator::writeMakeParts(QTextStream &t)
 
             QString src[] = { "SOURCES", "GENERATED_SOURCES", QString() };
             for(int x = 0; !src[x].isNull(); x++) {
-                QStringList &l = project->values(src[x]);
-                for(QStringList::Iterator it = l.begin(); it != l.end(); ++it) {
+                const QStringList &l = project->values(src[x]);
+                for (QStringList::ConstIterator it = l.begin(); it != l.end(); ++it) {
                     if(!(*it).isEmpty()) {
                         QString d_file;
                         for(QStringList::Iterator cit = Option::c_ext.begin();
@@ -343,15 +345,15 @@ UnixMakefileGenerator::writeMakeParts(QTextStream &t)
         if(!project->isEmpty("SUBLIBS_DIR"))
             libdir = project->first("SUBLIBS_DIR");
         t << "SUBLIBS       = ";
-        QStringList &l = project->values("SUBLIBS");
-        for(QStringList::Iterator it = l.begin(); it != l.end(); ++it)
+        const QStringList &l = project->values("SUBLIBS");
+        for (QStringList::ConstIterator it = l.begin(); it != l.end(); ++it)
             t << libdir << project->first("QMAKE_PREFIX_STATICLIB") << (*it) << "."
               << project->first("QMAKE_EXTENSION_STATICLIB") << " ";
         t << endl << endl;
     }
     if(project->isActiveConfig("depend_prl") && !project->isEmpty("QMAKE_PRL_INTERNAL_FILES")) {
-        QStringList &l = project->values("QMAKE_PRL_INTERNAL_FILES");
-        QStringList::Iterator it;
+        const QStringList &l = project->values("QMAKE_PRL_INTERNAL_FILES");
+        QStringList::ConstIterator it;
         for(it = l.begin(); it != l.end(); ++it) {
             QMakeMetaInfo libinfo;
             if(libinfo.readLib((*it)) && !libinfo.isEmpty("QMAKE_PRL_BUILD_DIR")) {
@@ -886,7 +888,7 @@ UnixMakefileGenerator::writeMakeParts(QTextStream &t)
         QString libdir = "tmp/";
         if(!project->isEmpty("SUBLIBS_DIR"))
             libdir = project->first("SUBLIBS_DIR");
-        QStringList &l = project->values("SUBLIBS");
+        const QStringList &l = project->values("SUBLIBS");
         for(it = l.begin(); it != l.end(); ++it)
             t << libdir << project->first("QMAKE_PREFIX_STATICLIB") << (*it) << "."
               << project->first("QMAKE_EXTENSION_STATICLIB") << ":\n\t"
diff --git a/qmake/generators/win32/borland_bmake.cpp b/qmake/generators/win32/borland_bmake.cpp
index 4c4ddf642e..110e2eafa6 100644
--- a/qmake/generators/win32/borland_bmake.cpp
+++ b/qmake/generators/win32/borland_bmake.cpp
@@ -57,7 +57,7 @@ BorlandMakefileGenerator::writeMakefile(QTextStream &t)
 {
     writeHeader(t);
     if(!project->values("QMAKE_FAILED_REQUIREMENTS").isEmpty()) {
-        QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
+        const QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
         for(QStringList::ConstIterator it = qut.begin(); it != qut.end(); ++it)
             t << *it << " ";
         t << "all first clean:" << "\n\t"
diff --git a/qmake/generators/win32/mingw_make.cpp b/qmake/generators/win32/mingw_make.cpp
index e62221e636..568e60a068 100644
--- a/qmake/generators/win32/mingw_make.cpp
+++ b/qmake/generators/win32/mingw_make.cpp
@@ -91,8 +91,8 @@ bool MingwMakefileGenerator::findLibraries(const QString &where)
 
     QList<QMakeLocalFileName> dirs;
     {
-        QStringList &libpaths = project->values("QMAKE_LIBDIR");
-        for(QStringList::Iterator libpathit = libpaths.begin();
+        const QStringList &libpaths = project->values("QMAKE_LIBDIR");
+        for (QStringList::ConstIterator libpathit = libpaths.begin();
             libpathit != libpaths.end(); ++libpathit)
             dirs.append(QMakeLocalFileName((*libpathit)));
     }
@@ -148,7 +148,7 @@ bool MingwMakefileGenerator::writeMakefile(QTextStream &t)
 
         if(Option::mkfile::do_stub_makefile) {
             t << "QMAKE    = " << var("QMAKE_QMAKE") << endl;
-            QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
+            const QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
             for(QStringList::ConstIterator it = qut.begin(); it != qut.end(); ++it)
                 t << *it << " ";
             t << "first all clean install distclean uninstall: qmake" << endl
@@ -344,8 +344,8 @@ void MingwMakefileGenerator::writeIncPart(QTextStream &t)
 {
     t << "INCPATH       = ";
 
-    QStringList &incs = project->values("INCLUDEPATH");
-    for(QStringList::Iterator incit = incs.begin(); incit != incs.end(); ++incit) {
+    const QStringList &incs = project->values("INCLUDEPATH");
+    for (QStringList::ConstIterator incit = incs.begin(); incit != incs.end(); ++incit) {
         QString inc = (*incit);
         inc.replace(QRegExp("\\\\$"), "");
         inc.replace(QRegExp("\""), "");
diff --git a/qmake/generators/win32/msvc_nmake.cpp b/qmake/generators/win32/msvc_nmake.cpp
index adf8883b01..0107f025eb 100644
--- a/qmake/generators/win32/msvc_nmake.cpp
+++ b/qmake/generators/win32/msvc_nmake.cpp
@@ -59,8 +59,8 @@ NmakeMakefileGenerator::writeMakefile(QTextStream &t)
 {
     writeHeader(t);
     if(!project->values("QMAKE_FAILED_REQUIREMENTS").isEmpty()) {
-        QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
-        for(QStringList::ConstIterator it = qut.begin(); it != qut.end(); ++it)
+        const QStringList &qut = project->values("QMAKE_EXTRA_TARGETS");
+        for (QStringList::ConstIterator it = qut.begin(); it != qut.end(); ++it)
             t << *it << " ";
         t << "all first clean:" << "\n\t"
           << "@echo \"Some of the required modules ("
@@ -332,8 +332,8 @@ void NmakeMakefileGenerator::writeImplicitRulesPart(QTextStream &t)
         }
         QString srcs[] = { QString("SOURCES"), QString("GENERATED_SOURCES"), QString() };
         for(int x = 0; !srcs[x].isNull(); x++) {
-            QStringList &l = project->values(srcs[x]);
-            for(QStringList::Iterator sit = l.begin(); sit != l.end(); ++sit) {
+            const QStringList &l = project->values(srcs[x]);
+            for (QStringList::ConstIterator sit = l.begin(); sit != l.end(); ++sit) {
                 QString sep = "\\";
                 if((*sit).indexOf(sep) == -1)
                     sep = "/";
diff --git a/qmake/generators/win32/msvc_objectmodel.h b/qmake/generators/win32/msvc_objectmodel.h
index 37d923f9c1..0d1e11b277 100644
--- a/qmake/generators/win32/msvc_objectmodel.h
+++ b/qmake/generators/win32/msvc_objectmodel.h
@@ -475,7 +475,7 @@ protected:
     virtual ~VCToolBase(){}
     virtual bool parseOption(const char* option) = 0;
 public:
-    void parseOptions(QStringList& options) {
+    void parseOptions(const QStringList& options) {
         for (QStringList::ConstIterator it=options.begin(); (it!=options.end()); it++)
             parseOption((*it).toLatin1().constData());
     }
diff --git a/qmake/generators/win32/msvc_vcproj.cpp b/qmake/generators/win32/msvc_vcproj.cpp
index b228917692..6fb73c0d50 100644
--- a/qmake/generators/win32/msvc_vcproj.cpp
+++ b/qmake/generators/win32/msvc_vcproj.cpp
@@ -1112,7 +1112,7 @@ void VcprojGenerator::initDeploymentTool()
 
     // Only deploy Qt libs for shared build
     if (!project->values("QMAKE_QT_DLL").isEmpty()) {
-        QStringList& arg = project->values("MSVCPROJ_LIBS");
+        const QStringList &arg = project->values("MSVCPROJ_LIBS");
         for (QStringList::ConstIterator it = arg.constBegin(); it != arg.constEnd(); ++it) {
             if (it->contains(project->first("QMAKE_LIBDIR"))) {
                 QString dllName = *it;
@@ -1471,8 +1471,8 @@ void VcprojGenerator::initOld()
     // $$QMAKE.. -> $$MSVCPROJ.. -------------------------------------
     project->values("MSVCPROJ_LIBS") += project->values("QMAKE_LIBS");
     project->values("MSVCPROJ_LIBS") += project->values("QMAKE_LIBS_PRIVATE");
-    QStringList &incs = project->values("INCLUDEPATH");
-    for(QStringList::Iterator incit = incs.begin(); incit != incs.end(); ++incit) {
+    const QStringList &incs = project->values("INCLUDEPATH");
+    for (QStringList::ConstIterator incit = incs.begin(); incit != incs.end(); ++incit) {
         QString inc = (*incit);
         if (!inc.startsWith('"') && !inc.endsWith('"'))
             inc = QString("\"%1\"").arg(inc); // Quote all paths if not quoted already
diff --git a/qmake/generators/win32/winmakefile.cpp b/qmake/generators/win32/winmakefile.cpp
index 895c331b21..319cd68338 100644
--- a/qmake/generators/win32/winmakefile.cpp
+++ b/qmake/generators/win32/winmakefile.cpp
@@ -110,8 +110,8 @@ Win32MakefileGenerator::findLibraries(const QString &where)
     QStringList &l = project->values(where);
     QList<QMakeLocalFileName> dirs;
     {
-        QStringList &libpaths = project->values("QMAKE_LIBDIR");
-        for(QStringList::Iterator libpathit = libpaths.begin();
+        const QStringList &libpaths = project->values("QMAKE_LIBDIR");
+        for (QStringList::ConstIterator libpathit = libpaths.begin();
             libpathit != libpaths.end(); ++libpathit)
             dirs.append(QMakeLocalFileName((*libpathit)));
     }
@@ -223,8 +223,8 @@ Win32MakefileGenerator::processPrlFiles()
     QHash<QString, bool> processed;
     QList<QMakeLocalFileName> libdirs;
     {
-        QStringList &libpaths = project->values("QMAKE_LIBDIR");
-        for(QStringList::Iterator libpathit = libpaths.begin(); libpathit != libpaths.end(); ++libpathit)
+        const QStringList &libpaths = project->values("QMAKE_LIBDIR");
+        for (QStringList::ConstIterator libpathit = libpaths.begin(); libpathit != libpaths.end(); ++libpathit)
             libdirs.append(QMakeLocalFileName((*libpathit)));
     }
     for(bool ret = false; true; ret = false) {
@@ -730,8 +730,8 @@ void Win32MakefileGenerator::writeStandardParts(QTextStream &t)
     if(!project->isEmpty("TRANSLATIONS"))
         dist_files << var("TRANSLATIONS");
     if(!project->isEmpty("FORMS")) {
-        QStringList &forms = project->values("FORMS");
-        for(QStringList::Iterator formit = forms.begin(); formit != forms.end(); ++formit) {
+        const QStringList &forms = project->values("FORMS");
+        for (QStringList::ConstIterator formit = forms.begin(); formit != forms.end(); ++formit) {
             QString ui_h = fileFixify((*formit) + Option::h_ext.first());
             if(exists(ui_h))
                 dist_files << ui_h;