How do I use CallStack?

Richard Eisenberg eir at
Mon Dec 7 19:25:26 UTC 2015

On Dec 7, 2015, at 2:23 PM, Eric Seidel <eric at> 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.


> Thanks!
> Eric

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