Fix crash in beam_bool

The following code crashes beam_bool:

bad(XDo1, XDo2, Do3) ->
    Do1 = (XDo1 =/= []),
    Do2 = (XDo2 =/= []),
    if Do1 =:= true;
       Do1 =:= false, Do2 =:= false, Do3 =:= delete ->
	    no
    end.

(Reported by Simon Cornish; minimized by Kostis Sagonas.)

For the moment fix the bug in the simplest and safest way possible
(basically, instead of crashing just don't do the optimization).

In a future major release (e.g. R14), the following improvements
could be considered:

* In beam_bool, it should be possible to move the Do1 and Do2
  expressions to the pre-block and still optimize the expression
  in the 'if' statement.

* In sys_core_fold, it should be possible to eliminate the
  try/catch around the guard expression in the 'if', because
  none of the guard tests can actually fail.

0 files changed, 0 insertions, 0 deletions