Goal:
    T : Prop  b : bool  H : ~ T  H0 : T
  ============================
   (is_true false)


DEBUG:Going to execute:
<coq-core.plugins.ltac::discriminate@0>
Level 0: Backtrace:

Proof is not complete.
Level 0: Backtrace:

Proof is not complete.
Level 0: Backtrace:

Proof is not complete.
Level 0: Backtrace:

Proof is not complete.
Level 0: Backtrace:

Proof is not complete.