From: "Iñaki Baz Castillo" <ibc@...>
Date: 2012-06-25T17:16:46+09:00
Subject: Re: have_func() does not find a func in the given .h file

2012/6/25 Eric Wong <normalperson@yhbt.net>:
> Iñaki Baz Castillo <ibc@aliax.net> wrote:
>>
>> /home/ibc/.rvm/repos/ruby$ grep ruby_thread_has_gvl_p vm_core.h
>> int ruby_thread_has_gvl_p(void);
>
> This is a private function, Ruby uses gcc -fvisibility=hidden to
> hide them and only exposes certain functions in vm_core.h
> via "#pragma GCC visibility ..."

Good to know.



>> But have_func() does not find it:
>
> have_func() doesn't parse C headers to find functions, but instead
> tries to link a C program to find the function.

Even better to know :)


>> Am I doint something wrong?
>
> You're relying too much on ever-changing Ruby internals :)

Well, it's just for temporal debugging purposes. I've
detected/experienced some changes in GVL stuf from 1.9.3 to trunk
version and ruby_thread_has_gvl_p() seems an useful debugging
function.


Thanks a lot.



-- 
Iñaki Baz Castillo
<ibc@aliax.net>