Solved Qt5.10 Windows: Error: 'glVertexAttrib2fv' was not declared in this scope?

[Eager]

I am trying to port my OpenGL project from GLFW to Qt 5.10.1 on Windows using MinGW but I am facing some issues. Everything was working perfect until I needed to use glVertexAttrib2fv which Qt says "was not declared in this scope"! I don't know what am I missing.

main.cpp

QSurfaceFormat format;
format.setVersion(4, 3);
format.setProfile(QSurfaceFormat::CoreProfile);
format.setDepthBufferSize(24);
format.setStencilBufferSize(8);
format.setSamples(10); 
QSurfaceFormat::setDefaultFormat(format);

myopenglwidget.h:

#include <QWidget>
#include <QOpenGLWidget>
#include <QOpenGLFunctions_4_3_Core>
#include <QOpenGLShaderProgram>

class MyOpenGLWidget : public QOpenGLWidget, protected QOpenGLFunctions_4_3_Core
{
protected:
    void initializeGL();
...
}

void MyOpenGLWidget::initializeGL()
{
    // initialize OpenGL Functions
    initializeOpenGLFunctions();
...
}

glVertexAttrib2fv is supported in all versions of OpenGL: https://www.khronos.org/registry/OpenGL-Refpages/gl4/html/glVertexAttrib.xhtml

Ask If more information is needed to solve this problem.

[Eager]

I found the solution, the trick was to use CompatibilityProfile rather than CoreProfile!

main.cpp

QSurfaceFormat format;
format.setVersion(4, 3);
format.setProfile(QSurfaceFormat::CompatibilityProfile);
format.setDepthBufferSize(24);
format.setStencilBufferSize(8);
format.setSamples(10); 
QSurfaceFormat::setDefaultFormat(format);

myopenglwidget.h:

#include <QWidget>
#include <QOpenGLWidget>
#include <QOpenGLFunctions_4_3_Compatibility>
#include <QOpenGLShaderProgram>

class MyOpenGLWidget : public QOpenGLWidget, protected QOpenGLFunctions_4_3_Compatibility
{
...
}

[Eager]

I found the solution, the trick was to use CompatibilityProfile rather than CoreProfile!

main.cpp

QSurfaceFormat format;
format.setVersion(4, 3);
format.setProfile(QSurfaceFormat::CompatibilityProfile);
format.setDepthBufferSize(24);
format.setStencilBufferSize(8);
format.setSamples(10); 
QSurfaceFormat::setDefaultFormat(format);

myopenglwidget.h:

#include <QWidget>
#include <QOpenGLWidget>
#include <QOpenGLFunctions_4_3_Compatibility>
#include <QOpenGLShaderProgram>

class MyOpenGLWidget : public QOpenGLWidget, protected QOpenGLFunctions_4_3_Compatibility
{
...
}