I am starting to learn qt-5 and trying to link two VBO’s to a vertex shader, one for position and another for color. I have declared them as in variables in the vertex shader under the names vertex and color. the problem is when using glGetAttribLocation, only vertex seems to be working even tho the two lines of code are written exactly the same.

vertexLoc = glGetAttribLocation (program->programId(), "vertex")// links it correctly but
colorLoc = glGetAttribLocation (program->programId(), "color") //does not

the error message reads:

error: 'colorLoc' was not declared in this scope  

my vertex and fragment shaders are

#version 330 core

in vec3 vertex;
in vec3 color;
out fcolor;

void main()  {
    gl_Position = vec4 (vertex, 1.0);
    fcolor=color;
}

and

#version 330 core

in  vec3 fcolor;
out vec4 FragColor;


void main() {
    FragColor = vec4(fcolor, 1);
}

respectivly