Compiling the minimal example below with -vtls says a global mutex is thread local. Is it supposed to be that way?

dmd v2.064
http://dpaste.dzfl.pl/74f9d635

Yes, global variables are thread-local by default. Use shared or _gshared
qualifier.
I guess such questions belong to D.learn.

On Monday, 2 December 2013 at 12:09:34 UTC, Artem Tarasov wrote:
> Yes, global variables are thread-local by default. Use shared or _gshared
> qualifier.
> I guess such questions belong to D.learn.

Is this really desired behaviour for mutexes? Since mutexes (per my rather little experience) is mostly used for locking between threads, which is not doable without extra qualifiers now.

I know that global variables are thread local, but using the mutex in different threads, which seems to be their main usage, require extra qualifiers. Shouldn't the main usage be possible using default setup, as in no extra qualifiers?

On 2013-12-02 16:44:24 +0000, Torje Digernes said:

> On Monday, 2 December 2013 at 12:09:34 UTC, Artem Tarasov wrote:
>> Yes, global variables are thread-local by default. Use shared or _gshared
>> qualifier.
>> I guess such questions belong to D.learn.
> 
> Is this really desired behaviour for mutexes? Since mutexes (per my rather little experience) is mostly used for locking between threads, which is not doable without extra qualifiers now.
> 
> I know that global variables are thread local, but using the mutex in different threads, which seems to be their main usage, require extra qualifiers. Shouldn't the main usage be possible using default setup, as in no extra qualifiers?

I don't think muticies should be turned into some special object that don't obey TLS default rules.   If you do pass an object between threads, it's mutex will be used appropriately (eg, via send/receive).  You're running into this because you used a global mutex -- I recently did the same thing.   Knowing about TLS though I declared it as __gshared on the first try and it worked.    It is a bit of a gotcha though.

On Tuesday, 3 December 2013 at 05:22:20 UTC, Shammah Chancellor wrote:
> On 2013-12-02 16:44:24 +0000, Torje Digernes said:
>
>> On Monday, 2 December 2013 at 12:09:34 UTC, Artem Tarasov wrote:

> used a global mutex -- I recently did the same thing.   Knowing about TLS though I declared it as __gshared on the first try

why such an ugly name for this qualifier?

On Tuesday, 3 December 2013 at 07:48:07 UTC, eles wrote:
> On Tuesday, 3 December 2013 at 05:22:20 UTC, Shammah Chancellor wrote:
>> On 2013-12-02 16:44:24 +0000, Torje Digernes said:
>>
>>> On Monday, 2 December 2013 at 12:09:34 UTC, Artem Tarasov wrote:
>
>> used a global mutex -- I recently did the same thing.   Knowing about TLS though I declared it as __gshared on the first try
>
> why such an ugly name for this qualifier?

Because it is dead unsafe.

On 12/3/2013 4:48 PM, eles wrote:
> On Tuesday, 3 December 2013 at 05:22:20 UTC, Shammah Chancellor wrote:
>> On 2013-12-02 16:44:24 +0000, Torje Digernes said:
>>
>>> On Monday, 2 December 2013 at 12:09:34 UTC, Artem Tarasov wrote:
>
>> used a global mutex -- I recently did the same thing.   Knowing about
>> TLS though I declared it as __gshared on the first try
>
> why such an ugly name for this qualifier?
>

Because "here be dragons." __gshared offers no guarantees and no safety. It shouldn't be used carelessly. It was made ugly intentionally.

An old thread on this topic: http://forum.dlang.org/thread/mailman.2017.1353214033.5162.digitalmars-d@puremagic.com Nothing has changed since then.

On 2.12.2013. 17:44, Torje Digernes wrote:
> On Monday, 2 December 2013 at 12:09:34 UTC, Artem Tarasov wrote:
>> Yes, global variables are thread-local by default. Use shared or _gshared
>> qualifier.
>> I guess such questions belong to D.learn.
> 
> Is this really desired behaviour for mutexes? Since mutexes (per my rather little experience) is mostly used for locking between threads, which is not doable without extra qualifiers now.
> 
> I know that global variables are thread local, but using the mutex in different threads, which seems to be their main usage, require extra qualifiers. Shouldn't the main usage be possible using default setup, as in no extra qualifiers?

Take into consideration that shared ( http://dlang.org/migrate-to-shared.html ) has not been fully implemented nor fully documented yet.

For more information check out: http://forum.dlang.org/thread/k7orpj$1tt5$1@digitalmars.com