So I have a very simple vertex shader as follows

#version 120
attribute vec3 position;
attribute vec3 inColor;
uniform mat4 mvp;
varying vec3 fragColor;

void main(void){
    fragColor = inColor;
    gl_Position = mvp * vec4(position, 1.0);
}

Which I load, as well as the fragment shader:

#version 120
varying vec3 fragColor;

void main(void) {
    gl_FragColor = vec4(fragColor,1.0);
}

Which I then load, compile, and link to my shader program. I check for link status using

glGetProgramiv(shaderProgram, GL_LINK_STATUS, &shaderSuccess);

which returns GL_TRUE so I think its ok. However, when I query the active attributes and uniforms using

#ifdef DEBUG
        int totalAttributes = -1;
        glGetProgramiv(shaderProgram, GL_ACTIVE_ATTRIBUTES, &totalAttributes);
        for(int i=0; i<totalAttributes; ++i)  {
            int name_len=-1, num=-1;
            GLenum type = GL_ZERO;
            char name[100];
            glGetActiveAttrib(shaderProgram, GLuint(i), sizeof(name)-1,
                               &name_len, &num, &type, name );
            name[name_len] = 0;
            GLuint location = glGetAttribLocation(shaderProgram, name);
            fprintf(stderr, "Attribute %s is bound at %d\n", name, location);
        }
        int totalUniforms = -1;
        glGetProgramiv(shaderProgram, GL_ACTIVE_UNIFORMS, &totalUniforms);
        for(int i=0; i<totalUniforms; ++i)  {
            int name_len=-1, num=-1;
            GLenum type = GL_ZERO;
            char name[100];
            glGetActiveUniform(shaderProgram, GLuint(i), sizeof(name)-1,
                              &name_len, &num, &type, name );
            name[name_len] = 0;
            GLuint location = glGetUniformLocation(shaderProgram, name);
            fprintf(stderr, "Uniform %s is bound at %d\n", name, location);
        }
#endif

I get:

Attribute inColor is bound at 0

Attribute position is bound at 1

Uniform mvp is bound at 0

Which leads to failure when trying to use the shader to render the objects. I have tried switching the order of declaration of position & inColor, but still, only position is bound with the other two giving 0

Can someone please explain why this is happening? Thanks