Compiler does not detect unassigned variable in some cases with if equations

[Adrian Pop]

The compiler does not detect that b3 is not assigned and because of that the behavior is undefined and random. See also 92eaf4/OMCompiler

protected function inlineWhenEq
  "inlines function calls in when equations"
  input BackendDAE.WhenEquation inWhenEquation;
  input Inline.Functiontuple fns;
  input DAE.ElementSource inSource;
  output BackendDAE.WhenEquation outWhenEquation;
  output DAE.ElementSource outSource;
  output Boolean inlined;
algorithm
  (outWhenEquation,outSource,inlined) := matchcontinue(inWhenEquation)
    local
      DAE.ComponentRef cref;
      DAE.Exp e,e_1,cond;
      BackendDAE.WhenEquation weq,weq_1;
      DAE.ElementSource source;
      Boolean b1,b2,b3;
      list<DAE.Statement> assrtLst;
      BackendDAE.WhenEquation we, elsewe;
      Option<BackendDAE.WhenEquation> oelsewe;
      list<BackendDAE.WhenOperator> whenStmtLst;

    case BackendDAE.WHEN_STMTS(condition=cond, whenStmtLst=whenStmtLst, elsewhenPart = oelsewe)
      equation
        (cond, source, b1,_) = Inline.inlineExp(cond, fns, inSource);
        (whenStmtLst, b2) = inlineWhenOps(whenStmtLst, fns);

        if isSome(oelsewe) then
          SOME(elsewe) = oelsewe;
          (elsewe, source, b3) = inlineWhenEq(elsewe, fns, source);
          oelsewe = SOME(elsewe);
        else
          oelsewe = NONE();
          // the compiler does not detect that b3 is not assigned
          // b3 = false;
        end if;
      then (BackendDAE.WHEN_STMTS(cond, whenStmtLst, oelsewe), source, b1 or b2 or b3);

  end matchcontinue;
end inlineWhenEq;

[Adrian Pop]

See also #3412.