[FFmpeg-devel] Why 'You can only build one library type at once on MinGW'?

Uoti Urpala uoti.urpala
Fri May 11 23:52:58 CEST 2007


On Fri, 2007-05-11 at 23:18 +0200, Michael Niedermayer wrote:
> and yes your security critical libs can still be loaded at random addresses
> security critical libs per definition are not 4gb large ...

It's usually not the libraries that are security critical but the
processes using them. If you want to avoid known addresses then all
libraries in the process should be randomized.

> i hope even someone who doesnt understand how PIC works can see that it does
> take the pointer "last" from the GOT and then dereferences it which is
> double indirection
> this happen because some wise text x86-ABI or ELF or whatever _requires_ it
> IIRC

That depends on the visibility of the symbol. If you make the symbol
static or hidden ("library-wide static") then it does not need
indirection. Same for the less often used visibility values protected or
internal.





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