null pointer dereference detection in DMD

[Iain Buclaw]

On Saturday, 11 January 2025 at 02:01:50 UTC, Richard (Rikki) 
Andrew Cattermole wrote:
> On 11/01/2025 2:43 PM, Walter Bright wrote:
>> Curiously, compiling it with `gcc -O3` does not detect it. 
>> ImportC doesn't detect it, either, a choice made because some 
>> C code uses such a construct as a way to drop into the 
>> debugger.
>
> Yeah you didn't turn the warning on.

[...snip...]

> flags: ``-Wnull-dereference -O``
>

[...snip...]

> https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html
>

Ergo, gdc also warns about this with the same flags.

```
$ gdc nullptrdect.d -O -Wnull-dereference
nullptrdect.d: In function ‘D main’:
nullptrdect.d:3:10: warning: null pointer dereference 
[-Wnull-dereference]
     3 |     *ptr = 3;
       |          ^
```