[critical] intsets.missingOrExcl silently gives wrong result in some cases

[timotheecour]

intsets.missingOrExcl silently gives wrong result in some cases

Example

  import intsets
  var t: IntSet

  # these work
  t.incl 10
  doAssert not t.missingOrExcl(10)
  doAssert t.missingOrExcl(10)
  doAssert t.missingOrExcl(11)

  # let n = 30 # this would work
  let n = 40 # this will cause bug

  for i in 0..<n:
    t.incl(i)

  for i in 0..<n:
    doAssert i in t
    let isMissing = t.missingOrExcl(i)
    doAssert not isMissing, $i

Current Output

t10261.nim(86, 5) `not isMissing` 0 [AssertionError]

Expected Output

works

Additional Information

• bug in 3dad130 1.1.1
• bug in 1.0.6