What does -vtls compiler flag does and ...

[Stanislav Blinov]

On Wednesday, 3 October 2018 at 21:18:26 UTC, welkam wrote:
> On Wednesday, 3 October 2018 at 20:58:01 UTC, Stanislav Blinov 
> wrote:
>> No, all *static non-immutable* variables are thread-local by 
>> default, not just "all variables".
> I misspoke but this should write something
> https://run.dlang.io/is/3u1wFp

And it does print "testtest" when you run it. But there are no 
thread-local variables there, so the compiler doesn't print 
anything extra when compiling. That's what -vtls flag does: 
during compilation reports which variables are thread-local.

> If you look at asm output there are "call _d_arraycatT at PLT32" 
> instruction so those variables weren't optimized away and yet 
> no output to stdout.
>
> If remove that flag ldc now compiles dmd but lacks 
> optimizations so more work needs to be done.

I'm not sure I understand.