Error while testing the ruby binding for free_symbols

error_free_symbols_rcp

SymEngine
  SymEngine::Basic
    .new
      with no arguments
        returns a Basic object
    binary operations
      #+
        with another initialised Basic object as argument
          returns a initialised Basic object that is result of
                        self added to the argument
      #-
        with another initialised Basic object as argument
          returns a initialised Basic object that is result of
                        argument subtracted from self
      #*
        with another initialised Basic object as argument
          returns a initialised Basic object that is result of
                        self multiplied by the argument
      #/
        with another initialised Basic object as argument
          returns a initialised Basic object that is result of
                        self divided by the argument
      #**
        with another initialised Basic object as argument
          returns a initialised Basic object that is result of
                        self raised to the power of argument
      #==
        with another initialised Basic object as argument
          returns true if they are the same expression
                        false if not
      #!=
        with another initialised Basic object as argument
          returns true is they are not the same expression
                        false if they are
    unary operations
      #-@
        doesn't take any argument
          returns the negation of self
    #free_symbols
      with nothing as argument
y
z
SYMENGINE_ASSERT failed: /home/abinashmeher999/gsoc/symengine/symengine/symengine_rcp.h
function operator->(), line number 93 at 
ptr_ != nullptr
Aborted (core dumped)