defer-type-errors + unsafeCoerce

[guest]

When evidence of a ~ b is missing, -fdefer-type-errors uses error to coerce a to b. It would nice to allow to use unsafeCoerce instead; for example ' ' :: Int would give under favourable conditions 32.

[simonpj]

But under unfavourable conditions you get a segmentation fault! The whole point of -fdefer-type-errors is that you get the same guarantees about lack of seg-faults and memory safety for type in-correct programs that you get for type-correct cones. As  the paper discusses. So I don't propose to change this.

Simon