On 08/16/2016 07:21 AM, Kagamin via Digitalmars-d-learn wrote:
On Monday, 15 August 2016 at 01:53:33 UTC, Charles Hixson wrote:
If I modify the code to attempt to pass a Tid[] as a member of struct
Start I get:
/usr/include/dmd/phobos/std/concurrency.d(603): Error: static assert
"Aliases to mutable thread-local data not allowed."
test.d(47): instantiated from here: send!(Start)
and this seems to imply that the casting away of shared might also be
an unsafe access which just doesn't happen to be detected by the
library.
Currently not all types, that are supposed to be thread-safe, support
shared, e.g. Semaphore, so it doesn't necessarily mean that sharing
them is incorrect.
Thanks. But "not all types" is a bit worrisome. Fortunately it's just
as easy to pass a fixed length array of Tids through send, and that even
yields simpler code. The problems I was running into turned out to be
because there was a "local reference", i.e. the dynamic array. I just
wasn't understanding the error message. So now I don't need to use the
"shared data" that I was worrying about. I am a bit surprised, however,
as Tids include a private class reference, and it seems as if that
should raise the same error flag, but it doesn't.
Of course, the real problem is that just because concurrent software
seems to be working right when you test it doesn't say anything about
how it will perform under load...so I want to avoid anything even
questionable.
