configure fails to recognize static libmp3lame

[Basic.Master]

Distribution: Ubuntu MATE 16.04 AMD64

When I try to build ffmpeg from git in combination with a static libmp3lame, configure fails with the following result:

ERROR: libmp3lame >= 3.98.3 not found

Used command line:

./configure --enable-libmp3lame

Lame (version 3.99.5) was compiled with:

./configure --disable-shared

The reason is that the presence check in "configure" (line 5856; just search for ">= 3.98.3") is done by compiling a minimal C program that invokes the library.

However linking the static version of libmp3lame in addition to "-lmp3lame" (see end of the mentioned line of "configure") also requires "-lm" (/ffbuild/config.log shows math.h related error messages).

To solve this, "-lm" can just be appended to the end of the mentioned "configure" line; afterwards, configure succeeds. Please find the simple patch attached.

(the bug occured in the first place when I tried to build libav as part of the VLC contribs, but I also reproduced it with the most recent git version of stand-alone ffmpeg).

Note that I also opened an issue at libav (unfortunately without success): ​https://bugzilla.libav.org/show_bug.cgi?id=1090

[Carl Eugen Hoyos]

Please send your patch to the FFmpeg development mailing list, patches are ignored here.

[James]

Fixed in c94b09485811b58a49e6769943509880922ff0bd