[Ffmpeg-devel] [PATCH] rtp.h warning

Måns Rullgård mans
Thu Mar 22 22:22:02 CET 2007


Rich Felker <dalias at aerifal.cx> writes:

> On Thu, Mar 22, 2007 at 09:07:40PM +0000, M?ns Rullg?rd wrote:
>> Rich Felker <dalias at aerifal.cx> writes:
>> 
>> > On Thu, Mar 22, 2007 at 02:12:05PM -0400, Glenn Maynard wrote:
>> >> Regarding XXX: is there a reason this isn't simply "const char
>> >> *enc_name"?  It'd save a few K on that table.
>> >
>> > Dunno the specifics here, but using const char * instead of const
>> > char[] in tables is very bad with shared libaries. It greatly
>> > increases the startup time (relocations) and prevents the tables from
>> > being in shared memory.
>> 
>> Why is that so?
>
> Because the pointer is not a linktime constant. It depends on the
> address at which the library is loaded, which in turn depends on which
> other libraries have been loaded. Thus, the addresses in the table
> have to be patched in at runtime-link-time.

Of course.  It's quite obvious now that I think about it.

-- 
M?ns Rullg?rd
mans at mansr.com




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