[LLVMdev] C++ Constructors

[John Criswell]

Chris Lattner wrote:
> On Dec 11, 2008, at 2:35 PM, John Criswell wrote:
>
>   
>> Dear All,
>>
>> Are global static constructors called before main() in LLVM these days
>> using some behind-the-scenes magic that is not explicit in the LLVM
>> bitcode?
>>     
>
> It is explicit in the bitcode.  You should see an llvm.globalctors  
> global array that has function pointers for each initializer to run.
>   
Right, I saw that.  I just didn't see anything from main() calling those 
functions, which led me to believe that something else is calling those 
functions before main().

>>  In older versions of LLVM, llvm-gcc added an explicit function
>> call to __main() as the first instruction in main(); __main() would  
>> call
>> all global static constructors.  It seems __main() is now gone.
>>     
>
> Yep, __main is now gone, llvm.globalctors is king. :)
>   
I assume putting my constructor at the head of the llvm.globalctors list 
will force it to be run before anything else?  Is that correct?

-- John T.

> -Chris
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