[FFmpeg-devel] Memory leak using bitstream filters with shared libs

Uoti Urpala uoti.urpala
Sun Mar 9 19:52:37 CET 2008

On Sun, 2008-03-09 at 18:35 +0000, M?ns Rullg?rd wrote:
> Why can't the code that takes the address of a function get it from
> the GOT instead of returning the address of the PLT entry?  The only
> requirement for this to work would be forcing any functions whose
> addresses are taken to be resolved at load time.  There is no need for
> modifying code areas at runtime at all.

That IS what happens in PIC code. The issue that started this thread
happened because there was non-PIC code using the address in the
process. I already explained in reply to your earlier mail that the code
generated for ffmpeg.c ("movq   $0x4038a0,0x48(%rsp)") writes a direct
value that is included in the assembler instruction itself. You need to
use -fPIC if you want the compiler to generate extra indirection through
the GOT.

> Taking the address of function should give the same result everywhere,
> regardless of compiler/linker flags.  Anything else is in violation of
> the C standard.

What's your point here? You think a compiler or linker must not have
flags like -Bsymbolic that can generate behavior different from the C

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