beam_validator: Fix type subtraction on select_* and inequality

Type subtraction never resulted in the 'none' type, even when it
was obvious that it should. Once that was fixed it became apparent
that inequality checks also fell into the same subtraction trap
that the type pass warned about in a comment.

This then led to another funny problem with select_val, consider
the following code:

    {bif,'>=',{f,0},[{x,0},{integer,1}],{x,0}}.
    {select_val,{x,0},{f,70},{list,[{atom,false},{f,69},
                                    {atom,true},{f,68}]}}.

The validator knows that '>=' can only return a boolean, so once it
has subtracted 'false' and 'true' it killed the state because all
all valid branches had been taken, so validation would crash once
it tried to branch off the fail label.

0 files changed, 0 insertions, 0 deletions