diff --git a/Makefile b/Makefile
index 4c3fd4d..5e487f1 100644
--- a/Makefile
+++ b/Makefile
@@ -6,7 +6,7 @@
 #    By: tmaze <tmaze@student.42.fr>                +#+  +:+       +#+         #
 #                                                 +#+#+#+#+#+   +#+            #
 #    Created: 2018/04/07 12:47:06 by tmaze             #+#    #+#              #
-#    Updated: 2018/05/16 12:22:34 by tmaze            ###   ########.fr        #
+#    Updated: 2018/05/16 15:07:10 by tmaze            ###   ########.fr        #
 #                                                                              #
 #******************************************************************************#
 
@@ -32,7 +32,7 @@ $(NAME): $(OBJS)
 	ar rcs $(NAME) $(OBJS)
 
 %.o: %.c libft.h
-	$(CC) $(CCFLAGS) $(CCSTD) $(INCLS) -c $< -o $@
+	$(CC) $(CCFLAGS) $(CCSTD) $(INCLS) -g -c $< -o $@
 
 clean:
 	rm -f $(OBJS)
diff --git a/ft_strchr.c b/ft_strchr.c
index 87cae42..0eae992 100644
--- a/ft_strchr.c
+++ b/ft_strchr.c
@@ -6,7 +6,7 @@
 /*   By: tmaze <marvin@42.fr>                       +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2018/04/04 18:54:17 by tmaze             #+#    #+#             */
-/*   Updated: 2018/04/05 11:05:16 by tmaze            ###   ########.fr       */
+/*   Updated: 2018/05/16 15:09:08 by tmaze            ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -17,10 +17,13 @@ char	*ft_strchr(const char *s, int c)
 	int		i;
 	char	*tmp;
 
-	i = -1;
-	tmp = (char*)s;
-	while (++i == 0 || tmp[i - 1])
-		if (tmp[i] == c)
-			return (&tmp[i]);
+	if (s != NULL)
+	{
+		i = -1;
+		tmp = (char*)s;
+		while (++i == 0 || tmp[i - 1])
+			if (tmp[i] == c)
+				return (&tmp[i]);
+	}
 	return (NULL);
 }
diff --git a/ft_strlen.c b/ft_strlen.c
index d4d52b4..3b397c3 100644
--- a/ft_strlen.c
+++ b/ft_strlen.c
@@ -6,7 +6,7 @@
 /*   By: tmaze <marvin@42.fr>                       +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2018/04/03 15:33:37 by tmaze             #+#    #+#             */
-/*   Updated: 2018/04/04 14:39:59 by tmaze            ###   ########.fr       */
+/*   Updated: 2018/05/16 15:33:46 by tmaze            ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -17,7 +17,7 @@ size_t	ft_strlen(const char *s)
 	int i;
 
 	i = 0;
-	while (s[i])
+	while (s != NULL && s[i])
 		i++;
 	return (i);
 }