Re: How do I use CallStack?

Oh I forgot to mention that I was testing on my local branch which fixes precisely this kind of bug when the CallStack is used inside a let-binder, which is what happens in rewriteEqEvidence. So it looks like my patch takes care of this issue. Thanks for the report! Sent from my iPhone

On Dec 7, 2015, at 11:25, Richard Eisenberg wrote:

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On Dec 7, 2015, at 2:23 PM, Eric Seidel wrote:

After staring at your bug confusedly for a few minutes, wondering why I couldn't simplify it, I realized that the actual warning I was getting was in *mkTcTransCo*, not rewriteEqEvidence. mkTcTransCo does not in fact use a CallStack (by default) so the redundant constraint warning there would be correct. If I add a call to error, everything seems to check out.

Can you confirm?

No. I had modified mkTcTransCo to print out the call-stack, so that wasn't the problem. If you can't reproduce quickly, I'll take another look at this when I get a chance. Thanks for taking a pass.

Richard

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Thanks! Eric