Feature: Allow scientific notation for literals #1721
I think I'm getting this tracked down... looks like the following phrase could be the cause?
"Substituting negative values for unary subtractions"
Perhaps on this substitution, there is something about constants where the unary substraction isn't being respected, ergo constant folding ignores the negative sign.
Note: when using literals, it used to be acceptable to have >10 decimal places, giving the false impression that you could specify a decimal literal as having >10 decimal places. It would silently drop the extra digits in that case. Note: changed test case to gwei from szabo to "fix" the new conversion error