On 8/8/22 10:12 AM, ag0aep6g wrote:
On Monday, 8 August 2022 at 13:31:04 UTC, Steven Schveighoffer wrote:
On 8/8/22 6:17 AM, ag0aep6g wrote:
[...]
Never ever use `__gshared` ever. It's a glaring safety hole. Use
`shared` instead.
If you are interfacing with C, you need __gshared. But yeah, you
should use shared in this case.
A quick test suggests that `extern(C) extern shared` works fine.
As far as I can tell, `__gshared` is only ever ok-ish when you want to
access a shared C variable in a single-threaded program. And then you're
still setting yourself up for failure if you later add more threads.
So, never ever use `__gshared` (in multi-threaded code) ever.
C has no notion of shared, so it's not the right type. Putting `shared`
on it is kind of lying, and can lead to trouble. Better to be explicit
about what it is.
I'm not saying you should use `__gshared` liberally, or for cases where
you are using this only in D. But to say you should *never* use it is
incorrect.
-Steve
