#version 450
#extension GL_KHR_compute_shader_derivatives : require

// Test declarying the group layout ahead of the local size
layout(derivative_group_quadsKHR) in;
layout(local_size_x = 2, local_size_y = 2) in;

void main()
{
    float dx = dFdx(float(gl_LocalInvocationID.x));
}