GLEW giving bunch of uncoused errors

I'm trying to learn GLFW and i found a good tutorial online. I did everything they did but when i even try to write a line of code to main() a lot of errors occur.

The first two error given are

In file included from main.cpp:10:0:
/usr/include/GL/glew.h:15769:109: error: conflicting declaration ‘typedef void (* PFNGLGETFRAGMENTMATERIALIVSGIXPROC)(GLenum, GLenum, const GLint*)’
 typedef void (GLAPIENTRY * PFNGLGETFRAGMENTMATERIALIVSGIXPROC) (GLenum face, GLenum pname, const GLint* data);
                                                                                                             ^
In file included from /usr/include/GL/gl.h:2055:0,
                 from /usr/include/GLFW/glfw3.h:153,
                 from main.cpp:7:
/usr/include/GL/glext.h:11616:25: note: previous declaration as ‘typedef void (* PFNGLGETFRAGMENTMATERIALIVSGIXPROC)(GLenum, GLenum, GLint*)’
 typedef void (APIENTRYP PFNGLGETFRAGMENTMATERIALIVSGIXPROC) (GLenum face, GLenum pname, GLint *params);
                         ^

Followed by many errors that look like

In file included from main.cpp:10:0:
/usr/include/GL/glew.h:16432:17: error: ‘PFNGLCLIENTACTIVETEXTUREPROC’ does not name a type
 GLEW_FUN_EXPORT PFNGLCLIENTACTIVETEXTUREPROC __glewClientActiveTexture;
                 ^

Since there were to many error i will paste them in pastebin: here

My code is:

#include <iostream>
#include <GLFW/glfw.h>
#include <GL/glew.h>
 
int main()
{
    return 0;
}

I compile it using this command:

g++ -o exec main.cpp -I/usr/include/libdrm -lglfw -I/usr/include/libdrm -lGL -I/usr/include/libdrm -lGLEW -lGLU

I have everything installed and i can create GLFW programs without glew but glew seems to be causing those problems.

Thank you!

EDIT: I use Ubuntu if it matters.

Solution

from http://glew.sourceforge.net/install.html

Also, GLEW will warn you by issuing a preprocessor error in case you have included gl.h, glext.h, or glATI.h before glew.h.

I suspect that #include <GLFW/glfw.h> internally does one of these things. Try swapping the includes.

GLFW confirms: http://www.glfw.org/docs/3.0/build.html

If you are using an OpenGL extension loading library such as GLEW, the GLEW header should also be included before* the GLFW one. The GLEW header defines macros that disable any OpenGL header that the GLFW header includes and GLEW will work as expected.