syntax-highlighting strings incorrectly for strings in opascal-mode

Question

I write my projects in FreePascal and use opascal-mode to write it. I'm having a problem that this mode thinks that '\' is not a complete string, and hence all code after it is highlighted as a string. How can I change the opascal-mode (or add a hook) in which it will not try to parse the backslash as an escape character? In FreePascal, strings do not support backslash as an escape char.

I'm using GNU Emacs 24.5.1 and this is a sample code that when run in opascal-mode, it highlights everything after the '\' improperly:

// syntax_highlight.dpr                                                                                                                                                                                                

{$mode objfpc}{$H+}
program my_program;
uses Classes;

var newVal : char;

begin
  newVal := '\'; // syntax highlight breaks here!                                                                                                                                                                                                       
  if newVal = '''' then begin                                                                                                                                                                                          
    writeln('single quote');                                                                                                                                                                                                    
  end else if newVal = '\' then begin
    writeln('backslash');
  end;
end.

I've tried messing around with modify-syntax-entry, but nothing I tried worked.

---

EDIT: this is the fixed config in ~/.emacs after I've implemented @JeanPierre's fix

;; associate pascal files as opascal-mode                                                                                                                                                              
(add-to-list 'auto-mode-alist '("\\.pas$" . opascal-mode))
(let* ((pascal-files '(".pas" ".pp" ".inc" ".lpr" ".dpr"))
       (pascal-regexp (concat (regexp-opt pascal-files t) "\\'")))
  (add-to-list 'auto-mode-alist (cons pascal-regexp 'opascal-mode)))

;; don't escape backslashes in pascal    
(add-hook 'opascal-mode-hook
          (modify-syntax-entry ?\\ "."))

Answer 1

C-h s (describe-syntax) shows that \ indeed has escape syntax. You can change it with the following:

(defun my/make-backslash-punctuation ()
  (modify-syntax-entry ?\\ "."))

(add-hook 'opascal-mode-hook #'my/make-backslash-punctuation)