$ newrepo
  $ enable smartlog
  $ drawdag << 'EOS'
  > B C  # B has date 100000 0
  > |/   # C has date 200000 0
  > A
  > EOS
  $ hg bookmark -ir $A master
  $ hg log -r 'smartlog()' -T '{desc}\n'
  A
  B
  C
  $ hg log -r "smartlog($B)" -T '{desc}\n'
  A
  B
  $ hg log -r "smartlog(heads=$C, master=$B)" -T '{desc}\n'
  A
  B
  C
  $ hg log -r "smartlog(master=($A::)-$B-$C)" -T '{desc}\n'
  A
  B
  C