On Saturday, 9 March 2019 at 19:18:38 UTC, ANtlord wrote:
Hello everyone! I've encountered the problem which I already
encountered before. Unfortunately, I had no time in the
previous time to report and to talk about it. So I decided to
play making my own "malloc" function in pure D (betterC) at
this time. And I encountered the issue one more time. `this`
can be null. How? Please take a look at my project [0]. It gets
the current heap break and tries to increase via a free list.
So the segfault I meet happens there [1]. Tell me, please. What
do I wrong?
[0] https://github.com/ANtlord/deadmemory
[1]
https://github.com/ANtlord/deadmemory/blob/master/src/deadmemory/freelist.d#L56
You can end up with a null `this` reference if you dereference a
null pointer to a struct and then call a method on the result.
For example:
struct S
{
bool isThisNull() { return &this is null; }
}
void main()
{
import.std.stdio;
S* p = null;
writeln((*p).isThisNull); // true
}
Interactive version: https://run.dlang.io/is/fgT2rS
