diff --git a/qmake/project.cpp b/qmake/project.cpp
index 208d5b7d3e..7a5c953f02 100644
--- a/qmake/project.cpp
+++ b/qmake/project.cpp
@@ -614,10 +614,8 @@ QMakeProject::~QMakeProject()
 
 
 void
-QMakeProject::init(QMakeProperty *p, const QHash<QString, QStringList> *vars)
+QMakeProject::init(QMakeProperty *p)
 {
-    if(vars)
-        base_vars = *vars;
     if(!p) {
         prop = new QMakeProperty;
         own_prop = true;
@@ -631,7 +629,8 @@ QMakeProject::init(QMakeProperty *p, const QHash<QString, QStringList> *vars)
 
 QMakeProject::QMakeProject(QMakeProject *p, const QHash<QString, QStringList> *vars)
 {
-    init(p->properties(), vars ? vars : &p->variables());
+    init(p->properties());
+    base_vars = vars ? *vars : p->variables();
     for(QHash<QString, FunctionBlock*>::iterator it = p->replaceFunctions.begin(); it != p->replaceFunctions.end(); ++it) {
         it.value()->ref();
         replaceFunctions.insert(it.key(), it.value());
diff --git a/qmake/project.h b/qmake/project.h
index 4c99825317..6422ed1f32 100644
--- a/qmake/project.h
+++ b/qmake/project.h
@@ -106,17 +106,14 @@ class QMakeProject
     bool doProjectCheckReqs(const QStringList &deps, QHash<QString, QStringList> &place);
     bool doVariableReplace(QString &str, QHash<QString, QStringList> &place);
     QStringList doVariableReplaceExpand(const QString &str, QHash<QString, QStringList> &place, bool *ok=0);
-    void init(QMakeProperty *, const QHash<QString, QStringList> *);
+    void init(QMakeProperty *);
     QStringList &values(const QString &v, QHash<QString, QStringList> &place);
     void validateModes();
     void resolveSpec(QString *spec, const QString &qmakespec);
 
 public:
-    QMakeProject() { init(0, 0); }
-    QMakeProject(QMakeProperty *p) { init(p, 0); }
+    QMakeProject(QMakeProperty *p = 0) { init(p); }
     QMakeProject(QMakeProject *p, const QHash<QString, QStringList> *nvars=0);
-    QMakeProject(const QHash<QString, QStringList> &nvars) { init(0, &nvars); }
-    QMakeProject(QMakeProperty *p, const QHash<QString, QStringList> &nvars) { init(p, &nvars); }
     ~QMakeProject();
 
     void setExtraVars(const QHash<QString, QStringList> &_vars) { extra_vars = _vars; }