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digitalmars.D.learn - Can't send messages to tid spawned in a Windows DLL. Bug?

reply Atila Neves <atila.neves gmail.com> writes:
This fails for me in a DLL:

auto tid = spawn(&func);
assert(tid != Tid.init);

If I print out the tid, I find that its message box is null. This 
is odd, since according the code in std.concurrency there's 
nothing weird about how it gets a message box, it's just `auto 
spawnTid = Tid(new MessageBox);`. So... `new` is returning null???

The really weird thing is that a thread is spawned and func 
starts executing. I just can't send it any messages without 
crashing.

Atila
Feb 16
parent reply kinke <noone nowhere.com> writes:
On Thursday, 16 February 2017 at 12:07:40 UTC, Atila Neves wrote:
 This fails for me in a DLL:

 auto tid = spawn(&func);
 assert(tid != Tid.init);

 If I print out the tid, I find that its message box is null. 
 This is odd, since according the code in std.concurrency 
 there's nothing weird about how it gets a message box, it's 
 just `auto spawnTid = Tid(new MessageBox);`. So... `new` is 
 returning null???

 The really weird thing is that a thread is spawned and func 
 starts executing. I just can't send it any messages without 
 crashing.

 Atila
If you suspect `new` of returning null, a GC issue seems likely. Is your DLL linked statically against druntime, thus having its own GC? Or are you using a shared druntime (and thus GC) across multiple binaries?
Feb 16
parent Atila Neves <atila.neves gmail.com> writes:
On Thursday, 16 February 2017 at 15:14:25 UTC, kinke wrote:
 On Thursday, 16 February 2017 at 12:07:40 UTC, Atila Neves 
 wrote:
 This fails for me in a DLL:

 auto tid = spawn(&func);
 assert(tid != Tid.init);

 If I print out the tid, I find that its message box is null. 
 This is odd, since according the code in std.concurrency 
 there's nothing weird about how it gets a message box, it's 
 just `auto spawnTid = Tid(new MessageBox);`. So... `new` is 
 returning null???

 The really weird thing is that a thread is spawned and func 
 starts executing. I just can't send it any messages without 
 crashing.

 Atila
If you suspect `new` of returning null, a GC issue seems likely. Is your DLL linked statically against druntime, thus having its own GC? Or are you using a shared druntime (and thus GC) across multiple binaries?
Whatever's default on Windows 32-bit. The thing is, all other uses of GC allocations in the same DLL work as expected. Atila
Feb 16