Potential bug in check_value_tag_compatibility_enter

[mjguynn]

value @fmul_gpu_val(%a: f32, %b: f32) -> f32 {
    %result_t = call @fmul_gpu(%a, %b);
    %result = extract %result_t 0;
    return %result;
}
schedule @fmul_gpu_sched(%a_gpu: $gpu_f32_encoded, %b_gpu: $gpu_f32_encoded, %ab_gpu: $gpu_f32_empty) -> $gpu_f32_encoded {
    %_ = encode-do-gpu @fmul_gpu_val.%result_t(%a_gpu, %b_gpu) -> %ab_gpu;
    return %ab_gpu;
}

// ... in input slot declarations for @fmul_gpu_sched:
%ab_gpu : slot_info(value_tag output @fmul_gpu_val.%a, spatial_tag input @saxpy_spatial.%bs)

Error:
'Ill-formed: Operation { remote_node_id: RemoteNodeId { funclet_id: 10, node_id: 4 } } to Output { funclet_id: 5, index: 0 }', src\type_system\value_tag.rs:33:14

Note that funclet 5 is fmul_gpu_val and funclet 10 is the value function implemented by the scheduling funclet which is calling @fmul_gpu_sched. (Also, @fmul_gpu_val.%a refers to the first output of @fmul_gpu_val.)

[mjguynn]

I tried adding a case to value_tag to accept this, but that causes a different failure:
ir::ValueTag::Output{funclet_id, index} => panic!("{:?} can only appear in interface of funclet", value_tag),