Thread sanitizer detects atomicOp!"" as data races

[HK47196]

Hi, I'm not sure how well supported threadsanitizer is by LDC(it seems to work OK,) but using atomicOp!"" on the same variable seems to cause tsan to think it's a data race.

I'm not 100% sure this is a bug, as I'm not an expert with atomics.

I think it has to do with it not detecting atomicLoad as an atomic operation(??) as it says cas contains an atomic write, but it just calls atomicLoad a regular load.

Happens in both LDC 0.15.1 and a HEAD build.

example:

import core.atomic;
import std.parallelism;
import std.range;
import std.stdio;
void main(){
    shared(size_t) num = 0;
    foreach(k; parallel(iota(1_000))){
        atomicOp!"+="(num, k);
    }
    writeln(atomicLoad(num));
}

compile with: ldc -sanitize=thread filename.d

(BTW, this seems to output errors related to a potential deadlock aswell. I'm unsure if that's related to this bug.)

[JohanEngelen]

I cannot reproduce this with LDC 1.24.