diff --git a/src/ecl_fun.cpp b/src/ecl_fun.cpp
index 1676491..5a89fc9 100644
--- a/src/ecl_fun.cpp
+++ b/src/ecl_fun.cpp
@@ -621,7 +621,7 @@ static cl_object new_qt_object(void* pointer, uint unique, int id, bool finalize
     STATIC_SYMBOL_PKG (s_new_qt_object, "NEW-QT-OBJECT", "EQL")
     cl_object l_qt_object = cl_funcall(5,
                                        s_new_qt_object,
-                                       ecl_make_unsigned_integer((ulong)pointer),
+                                       ecl_make_unsigned_integer((void_star_int)pointer),
                                        ecl_make_unsigned_integer(unique),
                                        MAKE_FIXNUM(id),
                                        finalize ? Ct : Cnil);
@@ -1122,7 +1122,7 @@ static MetaArg toMetaArg(const QByteArray& sType, cl_object l_arg) {
         else if(sType.endsWith('*')) {
             if(sType.startsWith('Q') || sType.startsWith("const Q")) {
                 QtObject o = toQtObject(l_arg);
-                ulong l = (ulong)o.pointer;
+                void_star_int l = (void_star_int)o.pointer;
                 // cast from QObject to non QObject + multiple inheritance problem
                 // e.g. QGraphicsObject, which inherits both QObject and QGraphicsItem
                 int q = sType.indexOf('Q');
@@ -1286,7 +1286,7 @@ cl_object to_lisp_arg(const MetaArg& arg) {
                 else if("const char*" == sType) {
                     l_ret = STRING_COPY(*(char**)p); }
                 else {
-                    l_ret = ecl_make_unsigned_integer((ulong)*(void**)p); }}
+                    l_ret = ecl_make_unsigned_integer((void_star_int)*(void**)p); }}
             else if(T_QFileInfo == n)                        l_ret = from_qfileinfo(*(QFileInfo*)p);
             else if(T_QFileInfoList == n)                    l_ret = from_qfileinfolist(*(QFileInfoList*)p);
             else if(T_QGradientStop == n)                    l_ret = from_qgradientstop(*(QGradientStop*)p);
@@ -1892,7 +1892,7 @@ cl_object qinvoke_method2(cl_object l_obj, cl_object l_cast, cl_object l_name, c
                     int i = -1;
                     void* _this = 0;
                     if(this_arg) {
-                        ulong l = (ulong)obj.pointer;
+                        void_star_int l = (void_star_int)obj.pointer;
                         if(qobject_align) {
                             // cast from QObject to non QObject + multiple inheritance problem
                             l += sizeof(QObject); }
diff --git a/src/ecl_fun.h b/src/ecl_fun.h
index d0bf31f..37eaf58 100644
--- a/src/ecl_fun.h
+++ b/src/ecl_fun.h
@@ -219,6 +219,12 @@ typedef QListIterator<MetaArg>   MetaArgIterator;
 typedef QList<QByteArray>        StrList;
 typedef QList<int>               IntList;
 
+#ifdef Q_PROCESSOR_X86_64
+typedef qulonglong void_star_int;
+#else
+typedef qulong     void_star_int;
+#endif
+
 class QByteArray;
 class QObject;
 class QEvent;
diff --git a/src/eql.cpp b/src/eql.cpp
index 9b71fbb..1975be4 100644
--- a/src/eql.cpp
+++ b/src/eql.cpp
@@ -11,11 +11,11 @@ const char EQL::version[] = "16.11.1"; // Nov 2016
 
 extern "C" void ini_EQL(cl_object);
 
-static char* argv[] = {"EQL5"};
+static const char* _argv_[] = {"EQL5"};
 
 EQL::EQL() : QObject() {
     if(!cl_booted) {
-        cl_boot(1, argv); }
+        cl_boot(1, (char**)_argv_); }
     iniCLFunctions();
     LObjects::ini(this);
     read_VV(OBJNULL, ini_EQL); } // see "src/make-eql-lib.lisp"
@@ -146,7 +146,7 @@ void EQL::exec(QWidget* widget, const QString& lispFile, const QString& slimeHoo
     eval("(in-package :eql)");
     forms << QString("(set-home \"%1\")").arg(home())
           << QString("(defvar *qt-main* (qt-object %1 0 (qid \"%2\")))")
-                     .arg((ulong)widget)
+                     .arg((void_star_int)widget)
                      .arg(QString(LObjects::vanillaQtSuperClassName(widget->metaObject())))
           << QString("(export '*qt-main*)")
           << QString("(in-package :eql-user)")