On Thursday, 3 November 2022 at 15:40:02 UTC, H. S. Teoh wrote:
On Thu, Nov 03, 2022 at 04:41:14AM +0000, Siarhei Siamashka via
Digitalmars-d-learn wrote: [...]
```D
@safe:
import std.stdio;
class A {
void foo() { writeln("foo"); }
}
void main() {
auto a1 = new A;
a1.foo(); // prints "foo"
A a2;
a2.foo(); // Segmentation fault
}
```
[...]
D does not have the equivalent of C++'s allocating a class
instance on the stack. In D, all class instances are allocated
on the heap and class variables are references to them.
Declaring an instance of A as a local variable initializes it
to the null reference, so invoking a method on it rightly
segfaults.
T
I think his main problem will go away if the code just refuses to
compile, since it's known at compile time that one is trying to
dereference a `null` pointer
Check my post, `A& a;` refuses to compile in C++20 atleast,
asking to be explicitly initialized, thus averting the problem
altogether
