[fpc-devel] OO rewrite - technical questions

Michael Schnell mschnell at lumino.de
Tue Jul 20 11:45:59 CEST 2010

  On 07/20/2010 11:16 AM, Florian Klaempfl wrote:
> Michael Schnell schrieb:
>> AFAIK, in Linux the archs specs define which register is supposed to be
>> used as a theradvar pointer by compilers. There might be some archs that
>> don't define a register but a dedicated memory location, managed by the
>> OS when scheduling threads and processes, to be the threadvar pointer.
> Where can be a detailed specification of this found?

I found these:


> How does it handle
> dyn. loaded libs using thread vars?

The just  compiler addresses the threadvars relative to  a register 
instead of  the pointer to the global area  with normal globals. (Or 
with X86/32 using another segment register instead of the default DS). 
So regarding the code it's just another Global area, in realtime the 
base of same is switching automatically when the thread is scheduled.


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