I have found the problem, I was including the header INSIDE my namespace, so linker was looking for another namespace into std.
#ifndef MYNAME_MATH_H
#define MYNAME_MATH_H
#include <glm/glm.hpp> // Linker Work
namespace myname
{
//#define _GLIBCXX_USE_C99_MATH 1
//#include <glm/glm.hpp> // Make linker FAIL!
//typedef glm::vec2 Vector2;
//typedef glm::vec3 Vector3;
//typedef glm::vec4 Vector4;
}
#endif // MYNAME_MATH_H