Bug#851026: ffmpeg: FTBFS: ffconf.bVIjAhhQ.c:2: undefined reference to `dlopen'

[Adrian Bunk]

Control: retitle -1 ffmpeg: ChromaprintContext FTBFS
Control: forwarded -1 https://trac.ffmpeg.org/ticket/5997
Control: tags -1 fixed-upstream

On Sat, Jan 14, 2017 at 06:47:02AM +0100, Carl Eugen Hoyos wrote:
> The relevant lines in the build log are afaict:
> 
> src/libavformat/chromaprint.c: In function 'write_packet':
> src/libavformat/chromaprint.c:113:1: error: control reaches end of non-void 
> function [-Werror=return-type]
>  }
>  ^
> 
> The function looks like this:
> 
> static int write_packet(AVFormatContext *s, AVPacket *pkt)
> {
>     ChromaprintMuxContext *cpr = s->priv_data;
>     return chromaprint_feed(cpr->ctx, pkt->data, pkt->size / 2) ? 0 : 
> AVERROR(EINVAL);
> }
> 
> I guess this is a compiler bug.

No, you should only look at the first compile error in that file:

src/libavformat/chromaprint.c:42:24: error: field 'ctx' has incomplete type
     ChromaprintContext ctx;
                        ^~~
This is the actual error.

Whatever the compiler comes up with for cpr->ctx in the place you quoted 
might be garbage, but at that point it is already game over.

Upstream fix:
  http://git.videolan.org/?p=ffmpeg.git;a=commitdiff;h=581f93f37ef2e7a00662828ed0348d1edb9041fe

> Carl Eugen

cu
Adrian

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