[FFmpeg-devel] linker error

[Rémi Denis-Courmont]

Le 20 octobre 2022 10:29:47 GMT+03:00, "Helmut K. C. Tessarek" <tessarek at evermeet.cx> a écrit :
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>On 2022-10-20 02:48, Nicolas George wrote:
>> Possibly. But between a library and a final program, the one who is at 
>> fault when a non-namespaced symbol conflicts is the library.
>
>In theory I agree with you. However, libass has been using the same
>non-static read_file function for many, many years.
>
>Cheers,
>  K. C.
>
>- -- 
>regards Helmut K. C. Tessarek              KeyID 0x172380A011EF4944
>Key fingerprint = 8A55 70C1 BD85 D34E ADBC 386C 1723 80A0 11EF 4944
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>   Thou shalt not follow the NULL pointer for chaos and madness
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Hi,

However long libass has been doing this, it is wrong. If anything you are lucky that your setup detects the bug early on, during the build.

In other setups, duplicate symbols won't cause a build time errors. This bug will cause a program symbol to be overridden silently and trigger really weird and hard to debug side effects.

AFAICT, the question is not how long libass has been doing this. The question is why couldn't you fix your libass instance, and would you need to put a kludge into FFmpeg.