### Compilation failed:

error: 1: interface blocks are not allowed in this kind of program
layout(binding=456) buffer testBlock {
                           ^^^^^^^^^
error: 5: 'main' must return: 'vec4', 'float4', or 'half4'
void main() {
^^^^^^^^^^^
error: 6: unknown identifier 'sk_FragColor'
    sk_FragColor = half4(half(test.x));
    ^^^^^^^^^^^^
error: 6: unknown identifier 'test'
    sk_FragColor = half4(half(test.x));
                              ^^^^
4 errors