diff --git a/src/libs/ifc/xml/vdomdocument.h b/src/libs/ifc/xml/vdomdocument.h
index 98dbcc13b..4f4405388 100644
--- a/src/libs/ifc/xml/vdomdocument.h
+++ b/src/libs/ifc/xml/vdomdocument.h
@@ -35,7 +35,6 @@
 #include <QDomNode>
 #include <QHash>
 #include <QLatin1String>
-#include <QLoggingCategory>
 #include <QStaticStringData>
 #include <QString>
 #include <QStringData>
diff --git a/src/libs/ifc/xml/vpatternconverter.h b/src/libs/ifc/xml/vpatternconverter.h
index eab0787e1..b233d6a7e 100644
--- a/src/libs/ifc/xml/vpatternconverter.h
+++ b/src/libs/ifc/xml/vpatternconverter.h
@@ -52,8 +52,14 @@ public:
 
     static const QString PatternMaxVerStr;
     static const QString CurrentSchema;
+// GCC 4.6 doesn't allow constexpr and const together
+#if defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__) > 406
     static Q_DECL_CONSTEXPR const int PatternMinVer = CONVERTER_VERSION_CHECK(0, 1, 0);
     static Q_DECL_CONSTEXPR const int PatternMaxVer = CONVERTER_VERSION_CHECK(0, 3, 3);
+#else
+    static Q_DECL_CONSTEXPR int PatternMinVer = CONVERTER_VERSION_CHECK(0, 1, 0);
+    static Q_DECL_CONSTEXPR int PatternMaxVer = CONVERTER_VERSION_CHECK(0, 3, 3);
+#endif
 
 protected:
     virtual int     MinVer() const Q_DECL_OVERRIDE;
diff --git a/src/libs/ifc/xml/vvitconverter.h b/src/libs/ifc/xml/vvitconverter.h
index 974a4fb4f..942ebf666 100644
--- a/src/libs/ifc/xml/vvitconverter.h
+++ b/src/libs/ifc/xml/vvitconverter.h
@@ -48,8 +48,14 @@ public:
 
     static const QString MeasurementMaxVerStr;
     static const QString CurrentSchema;
+// GCC 4.6 doesn't allow constexpr and const together
+#if defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__) > 406
     static Q_DECL_CONSTEXPR const int MeasurementMinVer = CONVERTER_VERSION_CHECK(0, 2, 0);
     static Q_DECL_CONSTEXPR const int MeasurementMaxVer = CONVERTER_VERSION_CHECK(0, 3, 3);
+#else
+    static Q_DECL_CONSTEXPR int MeasurementMinVer = CONVERTER_VERSION_CHECK(0, 2, 0);
+    static Q_DECL_CONSTEXPR int MeasurementMaxVer = CONVERTER_VERSION_CHECK(0, 3, 3);
+#endif
 
 protected:
     virtual int     MinVer() const Q_DECL_OVERRIDE;
diff --git a/src/libs/ifc/xml/vvstconverter.h b/src/libs/ifc/xml/vvstconverter.h
index 72e03a84a..39c07af07 100644
--- a/src/libs/ifc/xml/vvstconverter.h
+++ b/src/libs/ifc/xml/vvstconverter.h
@@ -48,8 +48,14 @@ public:
 
     static const QString MeasurementMaxVerStr;
     static const QString CurrentSchema;
+// GCC 4.6 doesn't allow constexpr and const together
+#if defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__) > 406
     static Q_DECL_CONSTEXPR const int MeasurementMinVer = CONVERTER_VERSION_CHECK(0, 3, 0);
     static Q_DECL_CONSTEXPR const int MeasurementMaxVer = CONVERTER_VERSION_CHECK(0, 4, 2);
+#else
+    static Q_DECL_CONSTEXPR int MeasurementMinVer = CONVERTER_VERSION_CHECK(0, 3, 0);
+    static Q_DECL_CONSTEXPR int MeasurementMaxVer = CONVERTER_VERSION_CHECK(0, 4, 2);
+#endif
 
 protected:
     virtual int     MinVer() const Q_DECL_OVERRIDE;
diff --git a/src/libs/vdxf/dxflib/dl_dxf.cpp b/src/libs/vdxf/dxflib/dl_dxf.cpp
index b1f082853..07c227692 100644
--- a/src/libs/vdxf/dxflib/dl_dxf.cpp
+++ b/src/libs/vdxf/dxflib/dl_dxf.cpp
@@ -26,8 +26,10 @@
 
 #include <ctype.h>
 #if defined(__GNUC__) && !defined(__APPLE__)
+#if (__GNUC__ * 100 + __GNUC_MINOR__) > 406
 #include <ext/alloc_traits.h>
 #endif
+#endif
 #include <qcompilerdetection.h>
 #include <string.h>
 #include <QString>
diff --git a/src/libs/vlayout/vbank.cpp b/src/libs/vlayout/vbank.cpp
index 0e29b5a4c..f28787391 100644
--- a/src/libs/vlayout/vbank.cpp
+++ b/src/libs/vlayout/vbank.cpp
@@ -28,7 +28,6 @@
 
 #include "vbank.h"
 
-#include <QLoggingCategory>
 #include <climits>
 
 #include "../vmisc/diagnostic.h"
diff --git a/src/libs/vmisc/vabstractapplication.cpp b/src/libs/vmisc/vabstractapplication.cpp
index a25060989..117ef8032 100644
--- a/src/libs/vmisc/vabstractapplication.cpp
+++ b/src/libs/vmisc/vabstractapplication.cpp
@@ -30,7 +30,6 @@
 
 #include <QDir>
 #include <QLibraryInfo>
-#include <QLoggingCategory>
 #include <QMessageLogger>
 #include <QStaticStringData>
 #include <QStringData>
@@ -40,6 +39,7 @@
 #include <QtDebug>
 
 #include "../vmisc/def.h"
+#include "../vmisc/logging.h"
 
 class QGraphicsScene;
 class QWidget;
diff --git a/src/libs/vmisc/vmath.h b/src/libs/vmisc/vmath.h
index 2cda433fe..a24c656b7 100644
--- a/src/libs/vmisc/vmath.h
+++ b/src/libs/vmisc/vmath.h
@@ -24,228 +24,7 @@
 #if QT_VERSION >= QT_VERSION_CHECK(5, 1, 0)
 #include <QtMath>
 #else
-
-#if 0
-#pragma qt_class(QtMath)
-#endif
-
-#include <math.h>
-
-#include <QtCore/qglobal.h>
-
-
-#define QT_SINE_TABLE_SIZE 256
-
-extern const qreal qt_sine_table[QT_SINE_TABLE_SIZE];
-
-inline int qCeil(qreal v)
-{
-#ifdef QT_USE_MATH_H_FLOATS
-    if (sizeof(qreal) == sizeof(float))
-        return int(ceilf(float(v)));
-    else
-#endif
-        return int(ceil(v));
-}
-
-inline int qFloor(qreal v)
-{
-#ifdef QT_USE_MATH_H_FLOATS
-    if (sizeof(qreal) == sizeof(float))
-        return int(floorf(float(v)));
-    else
-#endif
-        return int(floor(v));
-}
-
-inline qreal qFabs(qreal v)
-{
-#ifdef QT_USE_MATH_H_FLOATS
-    if(sizeof(qreal) == sizeof(float))
-        return fabsf(float(v));
-    else
-#endif
-        return fabs(v);
-}
-
-inline qreal qSin(qreal v)
-{
-#ifdef QT_USE_MATH_H_FLOATS
-    if (sizeof(qreal) == sizeof(float))
-        return sinf(float(v));
-    else
-#endif
-        return sin(v);
-}
-
-inline qreal qCos(qreal v)
-{
-#ifdef QT_USE_MATH_H_FLOATS
-    if (sizeof(qreal) == sizeof(float))
-        return cosf(float(v));
-    else
-#endif
-        return cos(v);
-}
-
-inline qreal qTan(qreal v)
-{
-#ifdef QT_USE_MATH_H_FLOATS
-    if (sizeof(qreal) == sizeof(float))
-        return tanf(float(v));
-    else
-#endif
-        return tan(v);
-}
-
-inline qreal qAcos(qreal v)
-{
-#ifdef QT_USE_MATH_H_FLOATS
-    if (sizeof(qreal) == sizeof(float))
-        return acosf(float(v));
-    else
-#endif
-       return acos(v);
-}
-
-inline qreal qAsin(qreal v)
-{
-#ifdef QT_USE_MATH_H_FLOATS
-    if (sizeof(qreal) == sizeof(float))
-        return asinf(float(v));
-    else
-#endif
-        return asin(v);
-}
-
-inline qreal qAtan(qreal v)
-{
-#ifdef QT_USE_MATH_H_FLOATS
-    if (sizeof(qreal) == sizeof(float))
-        return atanf(float(v));
-    else
-#endif
-        return atan(v);
-}
-
-inline qreal qAtan2(qreal y, qreal x)
-{
-#ifdef QT_USE_MATH_H_FLOATS
-    if (sizeof(qreal) == sizeof(float))
-        return atan2f(float(y), float(x));
-    else
-#endif
-        return atan2(y, x);
-}
-
-inline qreal qSqrt(qreal v)
-{
-#ifdef QT_USE_MATH_H_FLOATS
-    if (sizeof(qreal) == sizeof(float))
-        return sqrtf(float(v));
-    else
-#endif
-        return sqrt(v);
-}
-
-inline qreal qLn(qreal v)
-{
-#ifdef QT_USE_MATH_H_FLOATS
-    if (sizeof(qreal) == sizeof(float))
-        return logf(float(v));
-    else
-#endif
-        return log(v);
-}
-
-inline qreal qExp(qreal v)
-{
-    // only one signature
-    // exists, exp(double)
-    return exp(v);
-}
-
-inline qreal qPow(qreal x, qreal y)
-{
-#ifdef QT_USE_MATH_H_FLOATS
-    if (sizeof(qreal) == sizeof(float))
-        return powf(float(x), float(y));
-    else
-#endif
-        return pow(x, y);
-}
-
-#ifndef M_E
-#define M_E (2.7182818284590452354)
-#endif
-
-#ifndef M_LOG2E
-#define M_LOG2E (1.4426950408889634074)
-#endif
-
-#ifndef M_LOG10E
-#define M_LOG10E (0.43429448190325182765)
-#endif
-
-#ifndef M_LN2
-#define M_LN2 (0.69314718055994530942)
-#endif
-
-#ifndef M_LN10
-#define M_LN10 (2.30258509299404568402)
-#endif
-
-#ifndef M_PI
-#define M_PI (3.14159265358979323846)
-#endif
-
-#ifndef M_PI_2
-#define M_PI_2 (1.57079632679489661923)
-#endif
-
-#ifndef M_PI_4
-#define M_PI_4 (0.78539816339744830962)
-#endif
-
-#ifndef M_1_PI
-#define M_1_PI (0.31830988618379067154)
-#endif
-
-#ifndef M_2_PI
-#define M_2_PI (0.63661977236758134308)
-#endif
-
-#ifndef M_2_SQRTPI
-#define M_2_SQRTPI (1.12837916709551257390)
-#endif
-
-#ifndef M_SQRT2
-#define M_SQRT2 (1.41421356237309504880)
-#endif
-
-#ifndef M_SQRT1_2
-#define M_SQRT1_2 (0.70710678118654752440)
-#endif
-
-inline qreal qFastSin(qreal x)
-{
-    int si = int(x * (0.5 * QT_SINE_TABLE_SIZE / M_PI)); // Would be more accurate with qRound, but slower.
-    qreal d = x - si * (2.0 * M_PI / QT_SINE_TABLE_SIZE);
-    int ci = si + QT_SINE_TABLE_SIZE / 4;
-    si &= QT_SINE_TABLE_SIZE - 1;
-    ci &= QT_SINE_TABLE_SIZE - 1;
-    return qt_sine_table[si] + (qt_sine_table[ci] - 0.5 * qt_sine_table[si] * d) * d;
-}
-
-inline qreal qFastCos(qreal x)
-{
-    int ci = int(x * (0.5 * QT_SINE_TABLE_SIZE / M_PI)); // Would be more accurate with qRound, but slower.
-    qreal d = x - ci * (2.0 * M_PI / QT_SINE_TABLE_SIZE);
-    int si = ci + QT_SINE_TABLE_SIZE / 4;
-    si &= QT_SINE_TABLE_SIZE - 1;
-    ci &= QT_SINE_TABLE_SIZE - 1;
-    return qt_sine_table[si] - (qt_sine_table[ci] + 0.5 * qt_sine_table[si] * d) * d;
-}
+#include "qmath.h"
 
 Q_DECL_CONSTEXPR inline float qDegreesToRadians(float degrees)
 {
diff --git a/src/libs/vpatterndb/vcontainer.cpp b/src/libs/vpatterndb/vcontainer.cpp
index fb85a8d8a..9843c0659 100644
--- a/src/libs/vpatterndb/vcontainer.cpp
+++ b/src/libs/vpatterndb/vcontainer.cpp
@@ -29,7 +29,6 @@
 #include "vcontainer.h"
 
 #include <limits.h>
-#include <QLoggingCategory>
 #include <QVector>
 #include <QtDebug>
 
diff --git a/src/libs/vtools/dialogs/tools/dialogtool.h b/src/libs/vtools/dialogs/tools/dialogtool.h
index 51e098962..557878c5a 100644
--- a/src/libs/vtools/dialogs/tools/dialogtool.h
+++ b/src/libs/vtools/dialogs/tools/dialogtool.h
@@ -39,7 +39,6 @@
 #include <QList>
 #include <QListWidget>
 #include <QLocale>
-#include <QLoggingCategory>
 #include <QMap>
 #include <QMetaObject>
 #include <QObject>
diff --git a/src/libs/vtools/tools/drawTools/toolpoint/toolsinglepoint/vtoolsinglepoint.cpp b/src/libs/vtools/tools/drawTools/toolpoint/toolsinglepoint/vtoolsinglepoint.cpp
index df652e1e9..3ed3d2860 100644
--- a/src/libs/vtools/tools/drawTools/toolpoint/toolsinglepoint/vtoolsinglepoint.cpp
+++ b/src/libs/vtools/tools/drawTools/toolpoint/toolsinglepoint/vtoolsinglepoint.cpp
@@ -35,7 +35,6 @@
 #include <QGraphicsScene>
 #include <QGraphicsSceneMouseEvent>
 #include <QKeyEvent>
-#include <QLoggingCategory>
 #include <QPen>
 #include <QPoint>
 #include <QRectF>
@@ -50,6 +49,7 @@
 #include "../ifc/ifcdef.h"
 #include "../ifc/xml/vabstractpattern.h"
 #include "../vmisc/diagnostic.h"
+#include "../vmisc/logging.h"
 #include "../vgeometry/vgobject.h"
 #include "../vgeometry/vpointf.h"
 #include "../vmisc/vabstractapplication.h"
diff --git a/src/libs/vtools/tools/vdatatool.h b/src/libs/vtools/tools/vdatatool.h
index 6d33bd68f..ff1452932 100644
--- a/src/libs/vtools/tools/vdatatool.h
+++ b/src/libs/vtools/tools/vdatatool.h
@@ -30,7 +30,6 @@
 #define VDATATOOL_H
 
 #include <qcompilerdetection.h>
-#include <QLoggingCategory>
 #include <QMetaObject>
 #include <QObject>
 #include <QString>
diff --git a/src/libs/vtools/tools/vtooluniondetails.cpp b/src/libs/vtools/tools/vtooluniondetails.cpp
index 87c3c6dbf..0b7f7e6c2 100644
--- a/src/libs/vtools/tools/vtooluniondetails.cpp
+++ b/src/libs/vtools/tools/vtooluniondetails.cpp
@@ -32,7 +32,6 @@
 #include <QDomNodeList>
 #include <QHash>
 #include <QLineF>
-#include <QLoggingCategory>
 #include <QMessageLogger>
 #include <QSharedPointer>
 #include <QStaticStringData>
diff --git a/src/libs/vtools/undocommands/vundocommand.h b/src/libs/vtools/undocommands/vundocommand.h
index 95bb04312..31cd57570 100644
--- a/src/libs/vtools/undocommands/vundocommand.h
+++ b/src/libs/vtools/undocommands/vundocommand.h
@@ -31,7 +31,6 @@
 
 #include <qcompilerdetection.h>
 #include <QDomElement>
-#include <QLoggingCategory>
 #include <QMetaObject>
 #include <QObject>
 #include <QString>
diff --git a/src/libs/vtools/visualization/visualization.h b/src/libs/vtools/visualization/visualization.h
index bd95a32b8..d2e08ccd0 100644
--- a/src/libs/vtools/visualization/visualization.h
+++ b/src/libs/vtools/visualization/visualization.h
@@ -31,7 +31,6 @@
 
 #include <qcompilerdetection.h>
 #include <QGraphicsItem>
-#include <QLoggingCategory>
 #include <QObject>
 #include <QtGlobal>