Synthesis failes

[BasicEC]

Lua code:

function sum(x1, x2)
     x1 = x1 + x2
     x2 = x2 + 3
     sum(x1, x2)
end
sum(1,2,3)

DFG at the moment of stop:

[BasicEC]

My guess is that the FRAM can't overwrite x2 variable because it is needed for second add function. So we have dead lock here.

Maybe related: #213

[ryukzak]

Not reproduce. But highlight the following problem #267