On 19/02/16 12:04, Petr Spacek wrote:
Could you elaborate on this, please?
What is wrong with
if (ptr != NULL)
?
What standard says that it is wrong?
That isn't what's wrong. What is wrong is the method call that got you
there. You have a method like this:
void foo()
{
if (this != NULL) ...
}
and then you invoke it with a null pointer:
xxx->foo();
and it is that call that is not allowed by the standard when xxx is null.
So the compiler is allowed to assume that this will never be null in a
method, because calling a method on a null pointer is not allowed, so it
can just remove your null test in the method.
Then when you do call it on a null pointer you crash because the method
is not doing the null test and just tries to access members of the object.
Tom
--
Tom Hughes (tom@xxxxxxxxxx)
http://compton.nu/
--
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxxx
http://lists.fedoraproject.org/admin/lists/devel@xxxxxxxxxxxxxxxxxxxxxxx
