Windows DLLs and TLS

[Jakob Ovrum]

On Tuesday, 9 October 2012 at 10:21:58 UTC, Regan Heath wrote:
> On Mon, 08 Oct 2012 19:32:40 +0100, Jakob Ovrum 
> <jakobovrum at gmail.com> wrote:
>> XChat uses gmodule - part of glib - to load plugins. I looked 
>> at gmodule's Windows implementation, and it uses LoadLibraryW.
>
> Does your dummy C host application also use gmodule to load the 
> dll.. that might be a useful experiment perhaps.
>
> R

I tried this, and the results are illuminating.

I added gmodule support to the C host, enabling switching between 
using gmodule and direct WinAPI at the switch of a preprocessor 
define.

When the WinAPI is used directly, they get their correct 
initializers like before (I included some variables with explicit 
initializers too, like void* test3 = cast(void*)1).

When gmodule is used, the test TLS variables contain garbage! The 
garbage values are different every time the program runs.

I'll look closer at what gmodule is doing.